rt_api.c

/*
 * $Id$
 *
 * WKTRaster - Raster Types for PostGIS
 * http://trac.osgeo.org/postgis/wiki/WKTRaster
 *
 * Copyright (C) 2011-2012 Regents of the University of California
 *   <bkpark@ucdavis.edu>
 * Copyright (C) 2010-2011 Jorge Arevalo <jorge.arevalo@deimos-space.com>
 * Copyright (C) 2010-2011 David Zwarg <dzwarg@azavea.com>
 * Copyright (C) 2009-2011 Pierre Racine <pierre.racine@sbf.ulaval.ca>
 * Copyright (C) 2009-2011 Mateusz Loskot <mateusz@loskot.net>
 * Copyright (C) 2008-2009 Sandro Santilli <strk@keybit.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#include <math.h>
#include <stdio.h>  /* for printf (default message handler) */
#include <stdarg.h> /* for va_list, va_start etc */
#include <string.h> /* for memcpy and strlen */
#include <assert.h>
#include <time.h> /* for time */
#include "rt_api.h"
#include "gdal_vrt.h"

/******************************************************************************
 * Some rules for *.(c|h) files in rt_core
 *
 * All functions in rt_core that receive a band index parameter
 *   must be 0-based
 *****************************************************************************/

/*--- Utilities -------------------------------------------------*/

static void
swap_char(uint8_t *a, uint8_t *b) {
    uint8_t c = 0;

    assert(NULL != a && NULL != b);

    c = *a;
    *a = *b;
    *b = c;
}

static void
flip_endian_16(uint8_t *d) {
    assert(NULL != d);

    swap_char(d, d + 1);
}

static void
flip_endian_32(uint8_t *d) {
    assert(NULL != d);

    swap_char(d, d + 3);
    swap_char(d + 1, d + 2);
}

static void
flip_endian_64(uint8_t *d) {
    assert(NULL != d);

    swap_char(d + 7, d);
    swap_char(d + 6, d + 1);
    swap_char(d + 5, d + 2);
    swap_char(d + 4, d + 3);
}

uint8_t
rt_util_clamp_to_1BB(double value) {
    return (uint8_t)fmin(fmax((value), 0), POSTGIS_RT_1BBMAX);
}

uint8_t
rt_util_clamp_to_2BUI(double value) {
    return (uint8_t)fmin(fmax((value), 0), POSTGIS_RT_2BUIMAX);
}

uint8_t
rt_util_clamp_to_4BUI(double value) {
    return (uint8_t)fmin(fmax((value), 0), POSTGIS_RT_4BUIMAX);
}

int8_t
rt_util_clamp_to_8BSI(double value) {
    return (int8_t)fmin(fmax((value), SCHAR_MIN), SCHAR_MAX);
}

uint8_t
rt_util_clamp_to_8BUI(double value) {
    return (uint8_t)fmin(fmax((value), 0), UCHAR_MAX);
}

int16_t
rt_util_clamp_to_16BSI(double value) {
    return (int16_t)fmin(fmax((value), SHRT_MIN), SHRT_MAX);
}

uint16_t
rt_util_clamp_to_16BUI(double value) {
    return (uint16_t)fmin(fmax((value), 0), USHRT_MAX);
}

int32_t
rt_util_clamp_to_32BSI(double value) {
    return (int32_t)fmin(fmax((value), INT_MIN), INT_MAX);
}

uint32_t
rt_util_clamp_to_32BUI(double value) {
    return (uint32_t)fmin(fmax((value), 0), UINT_MAX);
}

float
rt_util_clamp_to_32F(double value) {
    return (float)fmin(fmax((value), -FLT_MAX), FLT_MAX);
}

/* quicksort */
#define SWAP(x, y) { double t; t = x; x = y; y = t; }
#define ORDER(x, y) if (x > y) SWAP(x, y)

static double pivot(double *left, double *right) {
	double l, m, r, *p;

	l = *left;
	m = *(left + (right - left) / 2);
	r = *right;

	/* order */
	ORDER(l, m);
	ORDER(l, r);
	ORDER(m, r);

	/* pivot is higher of two values */
	if (l < m) return m;
	if (m < r) return r;

	/* find pivot that isn't left */
	for (p = left + 1; p <= right; ++p) {
		if (*p != *left)
			return (*p < *left) ? *left : *p;
	}

	/* all values are same */
	return -1;
}

static double *partition(double *left, double *right, double pivot) {
	while (left <= right) {
		while (*left < pivot) ++left;
		while (*right >= pivot) --right;

		if (left < right) {
			SWAP(*left, *right);
			++left;
			--right;
		}
	}

	return left;
}

static void quicksort(double *left, double *right) {
	double p = pivot(left, right);
	double *pos;

	if (p != -1) {
		pos = partition(left, right, p);
		quicksort(left, pos - 1);
		quicksort(pos, right);
	}
}

/**
 * Convert cstring name to GDAL Resample Algorithm
 *
 * @param algname: cstring name to convert
 *
 * @return valid GDAL resampling algorithm
 */
GDALResampleAlg
rt_util_gdal_resample_alg(const char *algname) {
	if (!algname || !strlen(algname))	return GRA_NearestNeighbour;

	if (strcmp(algname, "NEARESTNEIGHBOUR") == 0)
		return GRA_NearestNeighbour;
	else if (strcmp(algname, "NEARESTNEIGHBOR") == 0)
		return GRA_NearestNeighbour;
	else if (strcmp(algname, "BILINEAR") == 0)
		return GRA_Bilinear;
	else if (strcmp(algname, "CUBICSPLINE") == 0)
		return GRA_CubicSpline;
	else if (strcmp(algname, "CUBIC") == 0)
		return GRA_Cubic;
	else if (strcmp(algname, "LANCZOS") == 0)
		return GRA_Lanczos;

	return GRA_NearestNeighbour;
}

/**
 * Convert rt_pixtype to GDALDataType
 *
 * @param pt: pixeltype to convert
 *
 * @return valid GDALDataType
 */
GDALDataType
rt_util_pixtype_to_gdal_datatype(rt_pixtype pt) {
	switch (pt) {
		case PT_1BB:
		case PT_2BUI:
		case PT_4BUI:
		case PT_8BUI:
			return GDT_Byte;
		case PT_8BSI:
		case PT_16BSI:
			return GDT_Int16;
		case PT_16BUI:
			return GDT_UInt16;
		case PT_32BSI:
			return GDT_Int32;
		case PT_32BUI:
			return GDT_UInt32;
		case PT_32BF:
			return GDT_Float32;
		case PT_64BF:
			return GDT_Float64;
		default:
			return GDT_Unknown;
	}

	return GDT_Unknown;
}

/**
 * Convert GDALDataType to rt_pixtype
 *
 * @param gdt: GDAL datatype to convert
 *
 * @return valid rt_pixtype
 */
rt_pixtype
rt_util_gdal_datatype_to_pixtype(GDALDataType gdt) {
	switch (gdt) {
		case GDT_Byte:
			return PT_8BUI;
		case GDT_UInt16:
			return PT_16BUI;
		case GDT_Int16:
			return PT_16BSI;
		case GDT_UInt32:
			return PT_32BUI;
		case GDT_Int32:
			return PT_32BSI;
		case GDT_Float32:
			return PT_32BF;
		case GDT_Float64:
			return PT_64BF;
		default:
			return PT_END;
	}

	return PT_END;
}

/*
	get GDAL runtime version information
*/
const char*
rt_util_gdal_version(const char *request) {
	if (NULL == request || !strlen(request))
		return GDALVersionInfo("RELEASE_NAME");
	else
		return GDALVersionInfo(request);
}

/*
	computed extent type
*/
rt_extenttype
rt_util_extent_type(const char *name) {
	if (strcmp(name, "UNION") == 0)
		return ET_UNION;
	else if (strcmp(name, "FIRST") == 0)
		return ET_FIRST;
	else if (strcmp(name, "SECOND") == 0)
		return ET_SECOND;
	else
		return ET_INTERSECTION;
}

char*
rt_util_gdal_convert_sr(const char *srs, int proj4) {
	OGRSpatialReferenceH hsrs;
	char *rtn = NULL;

	hsrs = OSRNewSpatialReference(NULL);
	if (OSRSetFromUserInput(hsrs, srs) == OGRERR_NONE) {
		if (proj4)
			OSRExportToProj4(hsrs, &rtn);
		else
			OSRExportToWkt(hsrs, &rtn);
	}
	else {
		rterror("rt_util_gdal_convert_sr: Could not process the provided srs: %s", srs);
		return NULL;
	}

	OSRDestroySpatialReference(hsrs);
	if (rtn == NULL) {
		rterror("rt_util_gdal_convert_sr: Could not process the provided srs: %s", srs);
		return NULL;
	}

	return rtn;
}

int
rt_util_gdal_supported_sr(const char *srs) {
	OGRSpatialReferenceH hsrs;
	OGRErr rtn = OGRERR_NONE;

	hsrs = OSRNewSpatialReference(NULL);
	rtn = OSRSetFromUserInput(hsrs, srs);
	OSRDestroySpatialReference(hsrs);

	if (rtn == OGRERR_NONE)
		return 1;
	else
		return 0;
}

int
rt_util_gdal_driver_registered(const char *drv) {
	int count = GDALGetDriverCount();
	int i = 0;
	GDALDriverH hdrv = NULL;

	if (drv == NULL || !strlen(drv) || count < 1)
		return 0;

	for (i = 0; i < count; i++) {
		hdrv = GDALGetDriver(i);
		if (hdrv == NULL) continue;

		if (strcmp(drv, GDALGetDriverShortName(hdrv)) == 0)
			return 1;
	}

	return 0;
}

void
rt_util_from_ogr_envelope(
	OGREnvelope	env,
	rt_envelope *ext
) {
	assert(ext != NULL);

	ext->MinX = env.MinX;
	ext->MaxX = env.MaxX;
	ext->MinY = env.MinY;
	ext->MaxY = env.MaxY;

	ext->UpperLeftX = env.MinX;
	ext->UpperLeftY = env.MaxY;
}

void
rt_util_to_ogr_envelope(
	rt_envelope ext,
	OGREnvelope	*env
) {
	assert(env != NULL);

	env->MinX = ext.MinX;
	env->MaxX = ext.MaxX;
	env->MinY = ext.MinY;
	env->MaxY = ext.MaxY;
}

LWPOLY *
rt_util_envelope_to_lwpoly(
	rt_envelope env
) {
	LWPOLY *npoly = NULL;
	POINTARRAY **rings = NULL;
	POINTARRAY *pts = NULL;
	POINT4D p4d;

	rings = (POINTARRAY **) rtalloc(sizeof (POINTARRAY*));
	if (!rings) {
		rterror("rt_util_envelope_to_lwpoly: Out of memory building envelope's geometry");
		return NULL;
	}
	rings[0] = ptarray_construct(0, 0, 5);
	if (!rings[0]) {
		rterror("rt_util_envelope_to_lwpoly: Out of memory building envelope's geometry ring");
		return NULL;
	}

	pts = rings[0];
	
	/* Upper-left corner (first and last points) */
	p4d.x = env.MinX;
	p4d.y = env.MaxY;
	ptarray_set_point4d(pts, 0, &p4d);
	ptarray_set_point4d(pts, 4, &p4d);

	/* Upper-right corner (we go clockwise) */
	p4d.x = env.MaxX;
	p4d.y = env.MaxY;
	ptarray_set_point4d(pts, 1, &p4d);

	/* Lower-right corner */
	p4d.x = env.MaxX;
	p4d.y = env.MinY;
	ptarray_set_point4d(pts, 2, &p4d);

	/* Lower-left corner */
	p4d.x = env.MinX;
	p4d.y = env.MinY;
	ptarray_set_point4d(pts, 3, &p4d);

	npoly = lwpoly_construct(SRID_UNKNOWN, 0, 1, rings);
	if (npoly == NULL) {
		rterror("rt_util_envelope_to_lwpoly: Unable to build envelope's geometry");
		return NULL;
	}

	return npoly;
}

/*- rt_context -------------------------------------------------------*/

/* Functions definitions */
void * init_rt_allocator(size_t size);
void * init_rt_reallocator(void * mem, size_t size);
void init_rt_deallocator(void * mem);
void init_rt_errorreporter(const char * fmt, va_list ap);
void init_rt_warnreporter(const char * fmt, va_list ap);
void init_rt_inforeporter(const char * fmt, va_list ap);



/*
 * Default allocators
 *
 * We include some default allocators that use malloc/free/realloc
 * along with stdout/stderr since this is the most common use case
 *
 */
void *
default_rt_allocator(size_t size)
{
    void *mem = malloc(size);
    return mem;
}

void *
default_rt_reallocator(void *mem, size_t size)
{
    void *ret = realloc(mem, size);
    return ret;
}

void
default_rt_deallocator(void *mem)
{
    free(mem);
}


void
default_rt_error_handler(const char *fmt, va_list ap) {

    static const char *label = "ERROR: ";
    char newfmt[1024] = {0};
    snprintf(newfmt, 1024, "%s%s\n", label, fmt);
    newfmt[1023] = '\0';

    vprintf(newfmt, ap);

    va_end(ap);
}

void
default_rt_warning_handler(const char *fmt, va_list ap) {

    static const char *label = "WARNING: ";
    char newfmt[1024] = {0};
    snprintf(newfmt, 1024, "%s%s\n", label, fmt);
    newfmt[1023] = '\0';

    vprintf(newfmt, ap);

    va_end(ap);
}


void
default_rt_info_handler(const char *fmt, va_list ap) {

    static const char *label = "INFO: ";
    char newfmt[1024] = {0};
    snprintf(newfmt, 1024, "%s%s\n", label, fmt);
    newfmt[1023] = '\0';

    vprintf(newfmt, ap);

    va_end(ap);
}


/**
 * Struct definition here
 */
struct rt_context_t {
    rt_allocator alloc;
    rt_reallocator realloc;
    rt_deallocator dealloc;
    rt_message_handler err;
    rt_message_handler warn;
    rt_message_handler info;
};

/* Static variable, to be used for all rt_core functions */
static struct rt_context_t ctx_t = {
    .alloc = init_rt_allocator,
    .realloc = init_rt_reallocator,
    .dealloc = init_rt_deallocator,
    .err = init_rt_errorreporter,
    .warn = init_rt_warnreporter,
    .info = init_rt_inforeporter
};


/**
 * This function is normally called by rt_init_allocators when no special memory
 * management is needed. Useful in raster core testing and in the (future)
 * loader, when we need to use raster core functions but we don't have
 * PostgreSQL backend behind. We must take care of memory by ourselves in those
 * situations
 */
void
rt_install_default_allocators(void)
{
    ctx_t.alloc = default_rt_allocator;
    ctx_t.realloc = default_rt_reallocator;
    ctx_t.dealloc = default_rt_deallocator;
    ctx_t.err = default_rt_error_handler;
    ctx_t.info = default_rt_info_handler;
    ctx_t.warn = default_rt_warning_handler;
}


/**
 * This function is called by rt_init_allocators when the PostgreSQL backend is
 * taking care of the memory and we want to use palloc family
 */
void
rt_set_handlers(rt_allocator allocator, rt_reallocator reallocator,
        rt_deallocator deallocator, rt_message_handler error_handler,
        rt_message_handler info_handler, rt_message_handler warning_handler) {

    ctx_t.alloc = allocator;
    ctx_t.realloc = reallocator;
    ctx_t.dealloc = deallocator;

    ctx_t.err = error_handler;
    ctx_t.info = info_handler;
    ctx_t.warn = warning_handler;
}



/**
 * Initialisation allocators
 *
 * These are used the first time any of the allocators are called to enable
 * executables/libraries that link into raster to be able to set up their own
 * allocators. This is mainly useful for older PostgreSQL versions that don't
 * have functions that are called upon startup.
 **/
void *
init_rt_allocator(size_t size)
{
    rt_init_allocators();

    return ctx_t.alloc(size);
}

void
init_rt_deallocator(void *mem)
{
    rt_init_allocators();

    ctx_t.dealloc(mem);
}


void *
init_rt_reallocator(void *mem, size_t size)
{
    rt_init_allocators();

    return ctx_t.realloc(mem, size);
}

void
init_rt_inforeporter(const char *fmt, va_list ap)
{
    rt_init_allocators();

    (*ctx_t.info)(fmt, ap);
}

void
init_rt_warnreporter(const char *fmt, va_list ap)
{
    rt_init_allocators();

    (*ctx_t.warn)(fmt, ap);
}


void
init_rt_errorreporter(const char *fmt, va_list ap)
{
    rt_init_allocators();

    (*ctx_t.err)(fmt, ap);

}



/**
 * Raster core memory management functions.
 *
 * They use the functions defined by the caller.
 */
void *
rtalloc(size_t size) {
    void * mem = ctx_t.alloc(size);
    RASTER_DEBUGF(5, "rtalloc called: %d@%p", size, mem);
    return mem;
}


void *
rtrealloc(void * mem, size_t size) {
    void * result = ctx_t.realloc(mem, size);
    RASTER_DEBUGF(5, "rtrealloc called: %d@%p", size, result);
    return result;
}

void
rtdealloc(void * mem) {
    ctx_t.dealloc(mem);
    RASTER_DEBUG(5, "rtdealloc called");
}

/**
 * Raster core error and info handlers
 *
 * Since variadic functions cannot pass their parameters directly, we need
 * wrappers for these functions to convert the arguments into a va_list
 * structure.
 */
void
rterror(const char *fmt, ...) {
    va_list ap;

    va_start(ap, fmt);

    /* Call the supplied function */
    (*ctx_t.err)(fmt, ap);

    va_end(ap);
}

void
rtinfo(const char *fmt, ...) {
    va_list ap;

    va_start(ap, fmt);

    /* Call the supplied function */
    (*ctx_t.info)(fmt, ap);

    va_end(ap);
}


void
rtwarn(const char *fmt, ...) {
    va_list ap;

    va_start(ap, fmt);

    /* Call the supplied function */
    (*ctx_t.warn)(fmt, ap);

    va_end(ap);
}



int
rt_util_dbl_trunc_warning(
	double initialvalue,
	int32_t checkvalint, uint32_t checkvaluint,
	float checkvalfloat, double checkvaldouble,
	rt_pixtype pixtype
) {
	int result = 0;

	switch (pixtype) {
		case PT_1BB:
		case PT_2BUI:
		case PT_4BUI:
		case PT_8BSI:
		case PT_8BUI:
		case PT_16BSI:
		case PT_16BUI:
		case PT_32BSI: {
			if (fabs(checkvalint - initialvalue) >= 1) {
#if POSTGIS_RASTER_WARN_ON_TRUNCATION > 0
				rtwarn("Value set for %s band got clamped from %f to %d",
					rt_pixtype_name(pixtype),
					initialvalue, checkvalint
				);
#endif
				result = 1;
			}
			else if (FLT_NEQ(checkvalint, initialvalue)) {
#if POSTGIS_RASTER_WARN_ON_TRUNCATION > 0
				rtwarn("Value set for %s band got truncated from %f to %d",
					rt_pixtype_name(pixtype),
					initialvalue, checkvalint
				);
#endif
				result = 1;
			}
			break;
		}
		case PT_32BUI: {
			if (fabs(checkvaluint - initialvalue) >= 1) {
#if POSTGIS_RASTER_WARN_ON_TRUNCATION > 0
				rtwarn("Value set for %s band got clamped from %f to %u",
					rt_pixtype_name(pixtype),
					initialvalue, checkvaluint
				);
#endif
				result = 1;
			}
			else if (FLT_NEQ(checkvaluint, initialvalue)) {
#if POSTGIS_RASTER_WARN_ON_TRUNCATION > 0
				rtwarn("Value set for %s band got truncated from %f to %u",
					rt_pixtype_name(pixtype),
					initialvalue, checkvaluint
				);
#endif
				result = 1;
			}
			break;
		}
		case PT_32BF: {
			/*
				For float, because the initial value is a double,
				there is very often a difference between the desired value and the obtained one
			*/
			if (FLT_NEQ(checkvalfloat, initialvalue)) {
#if POSTGIS_RASTER_WARN_ON_TRUNCATION > 0
				rtwarn("Value set for %s band got converted from %f to %f",
					rt_pixtype_name(pixtype),
					initialvalue, checkvalfloat
				);
#endif
				result = 1;
			}
			break;
		}
		case PT_64BF: {
			if (FLT_NEQ(checkvaldouble, initialvalue)) {
#if POSTGIS_RASTER_WARN_ON_TRUNCATION > 0
				rtwarn("Value set for %s band got converted from %f to %f",
					rt_pixtype_name(pixtype),
					initialvalue, checkvaldouble
				);
#endif
				result = 1;
			}
			break;
		}
		case PT_END:
			break;
	}

	return result;
}

/*--- Debug and Testing Utilities --------------------------------------------*/

#if POSTGIS_DEBUG_LEVEL > 2

static char*
d_binary_to_hex(const uint8_t * const raw, uint32_t size, uint32_t *hexsize) {
    char* hex = NULL;
    uint32_t i = 0;


    assert(NULL != raw);
    assert(NULL != hexsize);


    *hexsize = size * 2; /* hex is 2 times bytes */
    hex = (char*) rtalloc((*hexsize) + 1);
    if (!hex) {
        rterror("d_binary_to_hex: Out of memory hexifying raw binary");
        return NULL;
    }
    hex[*hexsize] = '\0'; /* Null-terminate */

    for (i = 0; i < size; ++i) {
        deparse_hex(raw[i], &(hex[2 * i]));
    }

    assert(NULL != hex);
    assert(0 == strlen(hex) % 2);
    return hex;
}

static void
d_print_binary_hex(const char* msg, const uint8_t * const raw, uint32_t size) {
    char* hex = NULL;
    uint32_t hexsize = 0;


    assert(NULL != msg);
    assert(NULL != raw);


    hex = d_binary_to_hex(raw, size, &hexsize);
    if (NULL != hex) {
        rtinfo("%s\t%s", msg, hex);
        rtdealloc(hex);
    }
}

static size_t
d_binptr_to_pos(const uint8_t * const ptr, const uint8_t * const end, size_t size) {
    assert(NULL != ptr && NULL != end);

    return (size - (end - ptr));
}

#define CHECK_BINPTR_POSITION(ptr, end, size, pos) \
    { if (pos != d_binptr_to_pos(ptr, end, size)) { \
    fprintf(stderr, "Check of binary stream pointer position failed on line %d\n", __LINE__); \
    fprintf(stderr, "\tactual = %lu, expected = %lu\n", (long unsigned)d_binptr_to_pos(ptr, end, size), (long unsigned)pos); \
    } }

#else

#define CHECK_BINPTR_POSITION(ptr, end, size, pos) ((void)0);

#endif /* ifndef POSTGIS_DEBUG_LEVEL > 3 */

/*- rt_pixeltype -----------------------------------------------------*/

int
rt_pixtype_size(rt_pixtype pixtype) {
	int pixbytes = -1;

	switch (pixtype) {
		case PT_1BB:
		case PT_2BUI:
		case PT_4BUI:
		case PT_8BSI:
		case PT_8BUI:
			pixbytes = 1;
			break;
		case PT_16BSI:
		case PT_16BUI:
			pixbytes = 2;
			break;
		case PT_32BSI:
		case PT_32BUI:
		case PT_32BF:
			pixbytes = 4;
			break;
		case PT_64BF:
			pixbytes = 8;
			break;
		default:
			rterror("rt_pixtype_size: Unknown pixeltype %d", pixtype);
			pixbytes = -1;
			break;
	}

	RASTER_DEBUGF(3, "Pixel type = %s and size = %d bytes",
		rt_pixtype_name(pixtype), pixbytes);

	return pixbytes;
}

int
rt_pixtype_alignment(rt_pixtype pixtype) {
	return rt_pixtype_size(pixtype);
}

rt_pixtype
rt_pixtype_index_from_name(const char* pixname) {
	assert(pixname && strlen(pixname) > 0);

	if (strcmp(pixname, "1BB") == 0)
		return PT_1BB;
	if (strcmp(pixname, "2BUI") == 0)
		return PT_2BUI;
	if (strcmp(pixname, "4BUI") == 0)
		return PT_4BUI;
	if (strcmp(pixname, "8BSI") == 0)
		return PT_8BSI;
	if (strcmp(pixname, "8BUI") == 0)
		return PT_8BUI;
	if (strcmp(pixname, "16BSI") == 0)
		return PT_16BSI;
	if (strcmp(pixname, "16BUI") == 0)
		return PT_16BUI;
	if (strcmp(pixname, "32BSI") == 0)
		return PT_32BSI;
	if (strcmp(pixname, "32BUI") == 0)
		return PT_32BUI;
	if (strcmp(pixname, "32BF") == 0)
		return PT_32BF;
	if (strcmp(pixname, "64BF") == 0)
		return PT_64BF;

	return PT_END;
}

const char*
rt_pixtype_name(rt_pixtype pixtype) {
	switch (pixtype) {
		case PT_1BB:
			return "1BB";
		case PT_2BUI:
			return "2BUI";
		case PT_4BUI:
			return "4BUI";
		case PT_8BSI:
			return "8BSI";
		case PT_8BUI:
			return "8BUI";
		case PT_16BSI:
			return "16BSI";
		case PT_16BUI:
			return "16BUI";
		case PT_32BSI:
			return "32BSI";
		case PT_32BUI:
			return "32BUI";
		case PT_32BF:
			return "32BF";
		case PT_64BF:
			return "64BF";
		default:
			rterror("rt_pixtype_name: Unknown pixeltype %d", pixtype);
			return "Unknown";
	}
}

/**
 * Return minimum value possible for pixel type
 *
 * @param pixtype: the pixel type to get minimum possible value for
 *
 * @return the minimum possible value for the pixel type.
 */
double
rt_pixtype_get_min_value(rt_pixtype pixtype) {
	switch (pixtype) {
		case PT_1BB:
		case PT_2BUI:
		case PT_4BUI:
		case PT_8BUI: {
			return (double) CHAR_MIN;
		}
		case PT_8BSI: {
			return (double) SCHAR_MIN;
		}
		case PT_16BSI:
		case PT_16BUI: {
			return (double) SHRT_MIN;
		}
		case PT_32BSI:
		case PT_32BUI: {
			return (double) INT_MIN;
		}
		case PT_32BF: {
			return (double) -FLT_MAX;
		}
		case PT_64BF: {
			return (double) -DBL_MAX;
		}
		default: {
			rterror("rt_pixtype_get_min_value: Unknown pixeltype %d", pixtype);
			return (double) CHAR_MIN;
		}
	}
}

/*- rt_pixel ----------------------------------------------------------*/

/*
 * Convert an array of rt_pixel objects to two 2D arrays of value and NODATA
 *
 * @param npixel: array of rt_pixel objects
 * @param count: number of elements in npixel
 * @param x: the column of the center pixel (0-based)
 * @param y: the line of the center pixel (0-based)
 * @param distance: the number of pixels around the center pixel
 * @param value: pointer to pointer for 2D value array
 * @param nodata: pointer to pointer for 2D NODATA array
 *
 * @return 0 on error, otherwise the X/Y axis length of value and NODATA 
 */
int rt_pixel_set_to_array(
	rt_pixel npixel, int count,
	int x, int y,
	uint16_t distance,
	double ***value,
	int ***nodata
) {
	uint32_t i;
	uint32_t j;
	uint32_t length = 0;
	double **values = NULL;
	int **nodatas = NULL;
	int zero[2] = {0};
	int _x;
	int _y;

	assert(npixel != NULL);
	assert(count > 0);

	/* length */
	length = distance * 2 + 1;
	RASTER_DEBUGF(4, "length = %d", length);

	/* establish 2D arrays */
	values = rtalloc(sizeof(double *) * length);
	nodatas = rtalloc(sizeof(int *) * length);

	if (values == NULL || nodatas == NULL) {
		rterror("rt_pixel_set_to_array: Unable to allocate memory for 2D array");
		return 0;
	}

	/* initialize */
	for (i = 0; i < length; i++) {
		values[i] = rtalloc(sizeof(double) * length);
		nodatas[i] = rtalloc(sizeof(int) * length);

		if (values[i] == NULL || nodatas[i] == NULL) {
			rterror("rt_pixel_set_to_array: Unable to allocate memory for dimension of 2D array");

			if (values[i] == NULL) {
				for (j = 0; j < i; j++) {
					rtdealloc(values[j]);
					rtdealloc(nodatas[j]);
				}
			}
			else {
				for (j = 0; j <= i; j++) {
					rtdealloc(values[j]);
					if (j < i)
						rtdealloc(nodatas[j]);
				}
			}

			rtdealloc(values);
			rtdealloc(nodatas);
			
			return 0;
		}

		/* set values to 0 */
		memset(values[i], 0, sizeof(double) * length);

		/* set nodatas to 1 */
		for (j = 0; j < length; j++)
			nodatas[i][j] = 1;
	}

	/* get zero, zero of grid */
	zero[0] = x - distance;
	zero[1] = y - distance;

	/* populate 2D arrays */
	for (i = 0; i < count; i++) {
		if (npixel[i].nodata)
			continue;

		_x = npixel[i].x - zero[0];
		_y = npixel[i].y - zero[1];

		RASTER_DEBUGF(4, "absolute x,y: %d x %d", npixel[i].x, npixel[i].y);
		RASTER_DEBUGF(4, "relative x,y: %d x %d", _x, _y);

		values[_x][_y] = npixel[i].value;
		nodatas[_x][_y] = 0;

		RASTER_DEBUGF(4, "(x, y, nodata, value) = (%d, %d, %d, %f)", _x, _y, nodatas[_x][_y], values[_x][_y]);
	}

	*value = &(*values);
	*nodata = &(*nodatas);

	return length;
}

/*- rt_band ----------------------------------------------------------*/

/**
 * Create an in-db rt_band with no data
 *
 * @param width     : number of pixel columns
 * @param height    : number of pixel rows
 * @param pixtype   : pixel type for the band
 * @param hasnodata : indicates if the band has nodata value
 * @param nodataval : the nodata value, will be appropriately
 *                    truncated to fit the pixtype size.
 * @param data      : pointer to actual band data, required to
 *                    be aligned accordingly to
 *                    rt_pixtype_aligment(pixtype) and big enough
 *                    to hold raster width*height values.
 *                    Data will NOT be copied, ownership is left
 *                    to caller which is responsible to keep it
 *                    allocated for the whole lifetime of the returned
 *                    rt_band.
 *
 * @return an rt_band, or 0 on failure
 */
rt_band
rt_band_new_inline(
	uint16_t width, uint16_t height,
	rt_pixtype pixtype,
	uint32_t hasnodata, double nodataval,
	uint8_t* data
) {
	rt_band band = NULL;

	assert(NULL != data);

	band = rtalloc(sizeof(struct rt_band_t));
	if (band == NULL) {
		rterror("rt_band_new_inline: Out of memory allocating rt_band");
		return NULL;
	}

	RASTER_DEBUGF(3, "Created rt_band @ %p with pixtype %s", band, rt_pixtype_name(pixtype));

	band->pixtype = pixtype;
	band->offline = 0;
	band->width = width;
	band->height = height;
	band->hasnodata = hasnodata;
	band->nodataval = 0;
	band->data.mem = data;
	band->ownsData = 0;
	band->isnodata = FALSE;
	band->raster = NULL;

	RASTER_DEBUGF(3, "Created rt_band with dimensions %d x %d", band->width, band->height);

	/* properly set nodataval as it may need to be constrained to the data type */
	if (hasnodata && rt_band_set_nodata(band, nodataval) < 0) {
		rterror("rt_band_new_inline: Unable to set NODATA value");
		rtdealloc(band);
		return NULL;
	}

	return band;
}

/**
 * Create an out-db rt_band
 *
 * @param width     : number of pixel columns
 * @param height    : number of pixel rows
 * @param pixtype   : pixel type for the band
 * @param hasnodata : indicates if the band has nodata value
 * @param nodataval : the nodata value, will be appropriately
 *                    truncated to fit the pixtype size.
 * @param bandNum   : 0-based band number in the external file
 *                    to associate this band with.
 * @param path      : NULL-terminated path string pointing to the file
 *                    containing band data. The string will NOT be
 *                    copied, ownership is left to caller which is
 *                    responsible to keep it allocated for the whole
 *                    lifetime of the returned rt_band.
 *
 * @return an rt_band, or 0 on failure
 */
rt_band
rt_band_new_offline(
	uint16_t width, uint16_t height,
	rt_pixtype pixtype,
	uint32_t hasnodata, double nodataval,
	uint8_t bandNum, const char* path
) {
	rt_band band = NULL;

	assert(NULL != path);

	band = rtalloc(sizeof(struct rt_band_t));
	if (band == NULL) {
		rterror("rt_band_new_offline: Out of memory allocating rt_band");
		return NULL;
	}

	RASTER_DEBUGF(3, "Created rt_band @ %p with pixtype %s",
		band, rt_pixtype_name(pixtype)
	); 

	band->pixtype = pixtype;
	band->offline = 1;
	band->width = width;
	band->height = height;
	band->hasnodata = hasnodata;
	band->nodataval = 0;
	band->isnodata = FALSE;
	band->raster = NULL;

	/* properly set nodataval as it may need to be constrained to the data type */
	if (hasnodata && rt_band_set_nodata(band, nodataval) < 0) {
		rterror("rt_band_new_offline: Unable to set NODATA value");
		rtdealloc(band);
		return NULL;
	}

	/* XXX QUESTION (jorgearevalo): What does exactly ownsData mean?? I think that
	 * ownsData = 0 ==> the memory for band->data is externally owned
	 * ownsData = 1 ==> the memory for band->data is internally owned
	 */
	band->ownsData = 0;

	band->data.offline.bandNum = bandNum;

	/* memory for data.offline.path should be managed externally */
	band->data.offline.path = (char *) path;

	band->data.offline.mem = NULL;

	return band;
}

/**
 * Create a new band duplicated from source band.  Memory is allocated
 * for band path (if band is offline) or band data (if band is online).
 * The caller is responsible for freeing the memory when the returned
 * rt_band is destroyed.
 *
 * @param : the band to copy
 *
 * @return an rt_band or NULL on failure
 */
rt_band
rt_band_duplicate(rt_band band) {
	rt_band rtn = NULL;
	assert(band != NULL);

	/* offline */
	if (band->offline) {
		char *path = NULL;
		path = rtalloc(sizeof(char) * (strlen(band->data.offline.path) + 1));
		if (path == NULL) {
			rterror("rt_band_duplicate: Out of memory allocating offline band path");
			return NULL;
		}
		strcpy(path, band->data.offline.path);

		rtn = rt_band_new_offline(
			band->width, band->height,
			band->pixtype,
			band->hasnodata, band->nodataval,
			band->data.offline.bandNum, (const char *) path
		);
	}
	/* online */
	else {
		uint8_t *data = NULL;
		data = rtalloc(rt_pixtype_size(band->pixtype) * band->width * band->height);
		if (data == NULL) {
			rterror("rt_band_duplicate: Out of memory allocating online band data");
			return NULL;
		}
		memcpy(data, band->data.mem, rt_pixtype_size(band->pixtype) * band->width * band->height);

		rtn = rt_band_new_inline(
			band->width, band->height,
			band->pixtype,
			band->hasnodata, band->nodataval,
			data
		);
	}

	if (rtn == NULL)
		rterror("rt_band_duplicate: Could not copy band");

	return rtn;
}

int
rt_band_is_offline(rt_band band) {

    assert(NULL != band);


    return band->offline;
}

/**
 * Destroy a raster band
 *
 * @param band : the band to destroy
 */
void
rt_band_destroy(rt_band band) {


    RASTER_DEBUGF(3, "Destroying rt_band @ %p", band);

		/* offline band and has data, free as data is internally owned */
		if (band->offline && band->data.offline.mem != NULL)
			rtdealloc(band->data.offline.mem);

    /* band->data content is externally owned */
    /* XXX jorgearevalo: not really... rt_band_from_wkb allocates memory for
     * data.mem
     */
    rtdealloc(band);
}

const char*
rt_band_get_ext_path(rt_band band) {

    assert(NULL != band);


    if (!band->offline) {
        RASTER_DEBUG(3, "rt_band_get_ext_path: Band is not offline");
        return 0;
    }
    return band->data.offline.path;
}

uint8_t
rt_band_get_ext_band_num(rt_band band) {

    assert(NULL != band);


    if (!band->offline) {
        RASTER_DEBUG(3, "rt_band_get_ext_path: Band is not offline");
        return 0;
    }
    return band->data.offline.bandNum;
}

/**
	* Get pointer to raster band data
	*
	* @param band : the band who's data to get
	*
	* @return void pointer to band data
	*/
void *
rt_band_get_data(rt_band band) {
	assert(NULL != band);

	if (band->offline) {
		int state = 0;

		if (band->data.offline.mem != NULL)
			return band->data.offline.mem;

		state = rt_band_load_offline_data(band);
		if (state == 0)
			return band->data.offline.mem;
		else
			return NULL;
	}
	else
		return band->data.mem;
}

/**
	* Load offline band's data.  Loaded data is internally owned
	* and should not be released by the caller.  Data will be
	* released when band is destroyed with rt_band_destroy().
	*
	* @param band : the band who's data to get
	*
	* @return 0 if success, non-zero if failure
	*/
int
rt_band_load_offline_data(rt_band band) {
	GDALDatasetH hdsSrc = NULL;
	int nband = 0;
	VRTDatasetH hdsDst = NULL;
	VRTSourcedRasterBandH hbandDst = NULL;
	double gt[6] = {0.};
	double ogt[6] = {0.};
	double offset[2] = {0};

	rt_raster _rast = NULL;
	rt_band _band = NULL;

	assert(band != NULL);
	assert(band->raster != NULL);

	if (!band->offline) {
		rterror("rt_band_load_offline_data: Band is not offline");
		return 1;
	}
	else if (!strlen(band->data.offline.path)) {
		rterror("rt_band_load_offline_data: Offline band does not a have a specified file");
		return 1;
	}

	GDALAllRegister();
	hdsSrc = GDALOpenShared(band->data.offline.path, GA_ReadOnly);
	if (hdsSrc == NULL) {
		rterror("rt_band_load_offline_data: Cannot open offline raster: %s", band->data.offline.path);
		return 1;
	}

	/* # of bands */
	nband = GDALGetRasterCount(hdsSrc);
	if (!nband) {
		rterror("rt_band_load_offline_data: No bands found in offline raster: %s", band->data.offline.path);
		GDALClose(hdsSrc);
		return 1;
	}
	/* bandNum is 0-based */
	else if (band->data.offline.bandNum + 1 > nband) {
		rterror("rt_band_load_offline_data: Specified band %d not found in offline raster: %s", band->data.offline.bandNum, band->data.offline.path);
		GDALClose(hdsSrc);
		return 1;
	}

	/* get raster's geotransform */
	rt_raster_get_geotransform_matrix(band->raster, gt);
	RASTER_DEBUGF(3, "Raster geotransform (%f, %f, %f, %f, %f, %f)",
		gt[0], gt[1], gt[2], gt[3], gt[4], gt[5]);

	/* get offline raster's geotransform */
	GDALGetGeoTransform(hdsSrc, ogt);
	RASTER_DEBUGF(3, "Offline geotransform (%f, %f, %f, %f, %f, %f)",
		ogt[0], ogt[1], ogt[2], ogt[3], ogt[4], ogt[5]);

	/* get offsets */
	rt_raster_geopoint_to_cell(
		band->raster,
		ogt[0], ogt[3],
		&(offset[0]), &(offset[1]),
		NULL
	);
	RASTER_DEBUGF(4, "offsets: (%f, %f)", offset[0], offset[1]);

	/* XXX: should there be a check for the spatial attributes between the offline raster file and that of the raster? */
	
	/* create VRT dataset */
	hdsDst = VRTCreate(band->width, band->height);
	GDALSetGeoTransform(hdsDst, gt);
	/*
	GDALSetDescription(hdsDst, "/tmp/offline.vrt");
	*/

	/* add band as simple sources */
	GDALAddBand(hdsDst, rt_util_pixtype_to_gdal_datatype(band->pixtype), NULL);
	hbandDst = (VRTSourcedRasterBandH) GDALGetRasterBand(hdsDst, 1);

	if (band->hasnodata)
		GDALSetRasterNoDataValue(hbandDst, band->nodataval);

	VRTAddSimpleSource(
		hbandDst, GDALGetRasterBand(hdsSrc, band->data.offline.bandNum + 1),
		abs(offset[0]), abs(offset[1]),
		band->width, band->height,
		0, 0,
		band->width, band->height,
		"near", VRT_NODATA_UNSET
	);

	/* make sure VRT reflects all changes */
	VRTFlushCache(hdsDst);

	/* convert VRT dataset to rt_raster */
	_rast = rt_raster_from_gdal_dataset(hdsDst);

	GDALClose(hdsDst);
	/* XXX: need to find a way to clean up the GDALOpenShared datasets at end of transaction */
	/* GDALClose(hdsSrc); */

	if (_rast == NULL) {
		rterror("rt_band_load_offline_data: Cannot load data from offline raster: %s", band->data.offline.path);
		return 1;
	}

	_band = rt_raster_get_band(_rast, 0);
	if (_band == NULL) {
		rterror("rt_band_load_offline_data: Cannot load data from offline raster: %s", band->data.offline.path);
		rt_raster_destroy(_rast);
		return 1;
	}

	/* band->data.offline.mem not NULL, free first */
	if (band->data.offline.mem != NULL) {
		rtdealloc(band->data.offline.mem);
		band->data.offline.mem = NULL;
	}

	band->data.offline.mem = _band->data.mem;

	rtdealloc(_band); /* cannot use rt_band_destory */
	rt_raster_destroy(_rast);

	return 0;
}

rt_pixtype
rt_band_get_pixtype(rt_band band) {

    assert(NULL != band);


    return band->pixtype;
}

uint16_t
rt_band_get_width(rt_band band) {

    assert(NULL != band);


    return band->width;
}

uint16_t
rt_band_get_height(rt_band band) {

    assert(NULL != band);


    return band->height;
}

#ifdef OPTIMIZE_SPACE

/*
 * Set given number of bits of the given byte,
 * starting from given bitOffset (from the first)
 * to the given value.
 *
 * Examples:
 *   char ch;
 *   ch=0; setBits(&ch, 1, 1, 0) -> ch==8
 *   ch=0; setBits(&ch, 3, 2, 1) -> ch==96 (0x60)
 *
 * Note that number of bits set must be <= 8-bitOffset
 *
 */
static void
setBits(char* ch, double val, int bits, int bitOffset) {
    char mask = 0xFF >> (8 - bits);
    char ival = val;


    assert(8 - bitOffset >= bits);

    RASTER_DEBUGF(4, "ival:%d bits:%d mask:%hhx bitoffset:%d\n",
            ival, bits, mask, bitOffset);

    /* clear all but significant bits from ival */
    ival &= mask;
#if POSTGIS_RASTER_WARN_ON_TRUNCATION > 0
    if (ival != val) {
        rtwarn("Pixel value for %d-bits band got truncated"
                " from %g to %hhu", bits, val, ival);
    }
#endif /* POSTGIS_RASTER_WARN_ON_TRUNCATION */

    RASTER_DEBUGF(4, " cleared ival:%hhx\n", ival);


    /* Shift ival so the significant bits start at
     * the first bit */
    ival <<= (8 - bitOffset - bits);

    RASTER_DEBUGF(4, " ival shifted:%hhx\n", ival);
    RASTER_DEBUGF(4, "  ch:%hhx\n", *ch);

    /* clear first bits of target */
    *ch &= ~(mask << (8 - bits - bitOffset));

    RASTER_DEBUGF(4, "  ch cleared:%hhx\n", *ch);

    /* Set the first bit of target */
    *ch |= ival;

    RASTER_DEBUGF(4, "  ch ored:%hhx\n", *ch);

}
#endif /* OPTIMIZE_SPACE */

int
rt_band_get_hasnodata_flag(rt_band band) {

    assert(NULL != band);


    return band->hasnodata;
}

void
rt_band_set_hasnodata_flag(rt_band band, int flag) {

    assert(NULL != band);


    band->hasnodata = (flag) ? 1 : 0;
}

void
rt_band_set_isnodata_flag(rt_band band, int flag) {

    assert(NULL != band);


    band->isnodata = (flag) ? 1 : 0;
}

int
rt_band_get_isnodata_flag(rt_band band) {

    assert(NULL != band);

    return band->isnodata;
}

/**
 * Set nodata value
 *
 * @param band : the band to set nodata value to
 * @param val : the nodata value
 *
 * @return 0 on success, -1 on error (invalid pixel type),
 *   1 on truncation/clamping/converting.
 */
int
rt_band_set_nodata(rt_band band, double val) {
    rt_pixtype pixtype = PT_END;
    /*
		double oldnodataval = band->nodataval;
		*/

    int32_t checkvalint = 0;
    uint32_t checkvaluint = 0;
    float checkvalfloat = 0;
    double checkvaldouble = 0;



    assert(NULL != band);

    pixtype = band->pixtype;

    RASTER_DEBUGF(3, "rt_band_set_nodata: setting nodata value %g with band type %s", val, rt_pixtype_name(pixtype));

    /* return -1 on out of range */
    switch (pixtype) {
        case PT_1BB:
        {
            band->nodataval = rt_util_clamp_to_1BB(val);
            checkvalint = band->nodataval;
            break;
        }
        case PT_2BUI:
        {
            band->nodataval = rt_util_clamp_to_2BUI(val);
            checkvalint = band->nodataval;
            break;
        }
        case PT_4BUI:
        {
            band->nodataval = rt_util_clamp_to_4BUI(val);
            checkvalint = band->nodataval;
            break;
        }
        case PT_8BSI:
        {
            band->nodataval = rt_util_clamp_to_8BSI(val);
            checkvalint = band->nodataval;
            break;
        }
        case PT_8BUI:
        {
            band->nodataval = rt_util_clamp_to_8BUI(val);
            checkvalint = band->nodataval;
            break;
        }
        case PT_16BSI:
        {
            band->nodataval = rt_util_clamp_to_16BSI(val);
            checkvalint = band->nodataval;
            break;
        }
        case PT_16BUI:
        {
            band->nodataval = rt_util_clamp_to_16BUI(val);
            checkvalint = band->nodataval;
            break;
        }
        case PT_32BSI:
        {
            band->nodataval = rt_util_clamp_to_32BSI(val);
            checkvalint = band->nodataval;
            break;
        }
        case PT_32BUI:
        {
            band->nodataval = rt_util_clamp_to_32BUI(val);
            checkvaluint = band->nodataval;
            break;
        }
        case PT_32BF:
        {
            band->nodataval = rt_util_clamp_to_32F(val);
            checkvalfloat = band->nodataval;
            break;
        }
        case PT_64BF:
        {
            band->nodataval = val;
            checkvaldouble = band->nodataval;
            break;
        }
        default:
            {
            rterror("rt_band_set_nodata: Unknown pixeltype %d", pixtype);
            band->hasnodata = 0;
            return -1;
        }
    }

    RASTER_DEBUGF(3, "rt_band_set_nodata: band->hasnodata = %d", band->hasnodata);
    RASTER_DEBUGF(3, "rt_band_set_nodata: band->nodataval = %f", band->nodataval);


    /* the nodata value was just set, so this band has NODATA */
    rt_band_set_hasnodata_flag(band, 1);

    /* If the nodata value is different from the previous one, we need to check
     * again if the band is a nodata band
     * TODO: NO, THAT'S TOO SLOW!!!
     */

    /*
    if (FLT_NEQ(band->nodataval, oldnodataval))
        rt_band_check_is_nodata(band);
    */

    if (rt_util_dbl_trunc_warning(
			val,
			checkvalint, checkvaluint,
			checkvalfloat, checkvaldouble,
			pixtype
		)) {
        return 1;
		}

    return 0;
}

/**
 * Set values of multiple pixels.  Unlike rt_band_set_pixel,
 * values in vals are expected to be of the band's pixel type
 * as this function uses memcpy.
 *
 * @param band : the band to set value to
 * @param x : X coordinate (0-based)
 * @param y : Y coordinate (0-based)
 * @param vals : the pixel values to apply
 * @param len : # of elements in vals
 *
 * @return 1 on success, 0 on error
 */
int
rt_band_set_pixel_line(
	rt_band band,
	int x, int y,
	void *vals, uint16_t len
) {
	rt_pixtype pixtype = PT_END;
	int size = 0;
	uint8_t *data = NULL;
	uint32_t offset = 0;

	assert(NULL != band);

	if (band->offline) {
		rterror("rt_band_set_pixel_line not implemented yet for OFFDB bands");
		return 0;
	}

	pixtype = band->pixtype;
	size = rt_pixtype_size(pixtype);

	if (
		x < 0 || x >= band->width ||
		y < 0 || y >= band->height
	) {
		rterror("rt_band_set_pixel_line: Coordinates out of range (%d, %d) vs (%d, %d)", x, y, band->width, band->height);
		return 0;
	}

	data = rt_band_get_data(band);
	offset = x + (y * band->width);
	RASTER_DEBUGF(5, "offset = %d", offset);

	/* make sure len of values to copy don't exceed end of data */
	if (len > (band->width * band->height) - offset) {
		rterror("rt_band_set_pixel_line: Unable to apply pixels as values length exceeds end of data");
		return 0;
	}

	switch (pixtype) {
		case PT_1BB:
		case PT_2BUI:
		case PT_4BUI:
		case PT_8BUI:
		case PT_8BSI: {
			uint8_t *ptr = data;
			ptr += offset;
			memcpy(ptr, vals, size * len);
			break;
		}
		case PT_16BUI: {
			uint16_t *ptr = (uint16_t *) data;
			ptr += offset;
			memcpy(ptr, vals, size * len);
			break;
		}
		case PT_16BSI: {
			int16_t *ptr = (int16_t *) data;
			ptr += offset;
			memcpy(ptr, vals, size * len);
			break;
		}
		case PT_32BUI: {
			uint32_t *ptr = (uint32_t *) data;
			ptr += offset;
			memcpy(ptr, vals, size * len);
			break;
		}
		case PT_32BSI: {
			int32_t *ptr = (int32_t *) data;
			ptr += offset;
			memcpy(ptr, vals, size * len);
			break;
		}
		case PT_32BF: {
			float *ptr = (float *) data;
			ptr += offset;
			memcpy(ptr, vals, size * len);
			break;
		}
		case PT_64BF: {
			double *ptr = (double *) data;
			ptr += offset;
			memcpy(ptr, vals, size * len);
			break;
		}
		default: {
			rterror("rt_band_set_pixel_line: Unknown pixeltype %d", pixtype);
			return 0;
		}
	}

#if POSTGIS_DEBUG_LEVEL > 0
	{
		double value;
		rt_band_get_pixel(band, x, y, &value);
		RASTER_DEBUGF(4, "pixel at (%d, %d) = %f", x, y, value);
	}
#endif

	return 1;
}

/**
 * Set single pixel's value
 *
 * @param band : the band to set value to
 * @param x : x ordinate (0-based)
 * @param y : y ordinate (0-based)
 * @param val : the pixel value
 *
 * @return 0 on success, -1 on error (value out of valid range),
 *   1 on truncation/clamping/converting.
 */
int
rt_band_set_pixel(
	rt_band band,
	int x, int y,
	double val
) {
	rt_pixtype pixtype = PT_END;
	unsigned char* data = NULL;
	uint32_t offset = 0;
	int rtn = 0;

	int32_t checkvalint = 0;
	uint32_t checkvaluint = 0;
	float checkvalfloat = 0;
	double checkvaldouble = 0;
	double checkval = 0;

	assert(NULL != band);

	if (band->offline) {
		rterror("rt_band_set_pixel not implemented yet for OFFDB bands");
		return -1;
	}

	pixtype = band->pixtype;

	if (
		x < 0 || x >= band->width ||
		y < 0 || y >= band->height
	) {
		rterror("rt_band_set_pixel: Coordinates out of range");
		return -1;
	}

	/* check that clamped value isn't clamped NODATA */
	if (band->hasnodata && pixtype != PT_64BF) {
		double newval;
		if (rt_band_corrected_clamped_value(band, val, &newval) == 1) {
#if POSTGIS_RASTER_WARN_ON_TRUNCATION > 0
			rtwarn("Value for pixel %d x %d has been corrected as clamped value becomes NODATA", x, y);
#endif
			val = newval;
			rtn = 1;
		}
	}

	data = rt_band_get_data(band);
	offset = x + (y * band->width);

	switch (pixtype) {
		case PT_1BB: {
			data[offset] = rt_util_clamp_to_1BB(val);
			checkvalint = data[offset];
			break;
		}
		case PT_2BUI: {
			data[offset] = rt_util_clamp_to_2BUI(val);
			checkvalint = data[offset];
			break;
		}
		case PT_4BUI: {
			data[offset] = rt_util_clamp_to_4BUI(val);
			checkvalint = data[offset];
			break;
		}
		case PT_8BSI: {
			data[offset] = rt_util_clamp_to_8BSI(val);
			checkvalint = (int8_t) data[offset];
			break;
		}
		case PT_8BUI: {
			data[offset] = rt_util_clamp_to_8BUI(val);
			checkvalint = data[offset];
			break;
		}
		case PT_16BSI: {
			int16_t *ptr = (int16_t*) data; /* we assume correct alignment */
			ptr[offset] = rt_util_clamp_to_16BSI(val);
			checkvalint = (int16_t) ptr[offset];
			break;
		}
		case PT_16BUI: {
			uint16_t *ptr = (uint16_t*) data; /* we assume correct alignment */
			ptr[offset] = rt_util_clamp_to_16BUI(val);
			checkvalint = ptr[offset];
			break;
		}
		case PT_32BSI: {
			int32_t *ptr = (int32_t*) data; /* we assume correct alignment */
			ptr[offset] = rt_util_clamp_to_32BSI(val);
			checkvalint = (int32_t) ptr[offset];
			break;
		}
		case PT_32BUI: {
			uint32_t *ptr = (uint32_t*) data; /* we assume correct alignment */
			ptr[offset] = rt_util_clamp_to_32BUI(val);
			checkvaluint = ptr[offset];
			break;
		}
		case PT_32BF: {
			float *ptr = (float*) data; /* we assume correct alignment */
			ptr[offset] = rt_util_clamp_to_32F(val);
			checkvalfloat = ptr[offset];
			break;
		}
		case PT_64BF: {
			double *ptr = (double*) data; /* we assume correct alignment */
			ptr[offset] = val;
			checkvaldouble = ptr[offset];
			break;
		}
		default: {
			rterror("rt_band_set_pixel: Unknown pixeltype %d", pixtype);
			return -1;
		}
	}

	/* If the stored value is different from no data, reset the isnodata flag */
	if (FLT_NEQ(checkval, band->nodataval)) {
		band->isnodata = FALSE;
	}

	/*
	 * If the pixel was a nodata value, now the band may be NODATA band)
	 * TODO: NO, THAT'S TOO SLOW!!!
	 */
	/*
	else {
		rt_band_check_is_nodata(band);
	}
	*/

	/* Overflow checking */
	if (rt_util_dbl_trunc_warning(
		val,
		checkvalint, checkvaluint,
		checkvalfloat, checkvaldouble,
		pixtype
	)) {
		return 1;
	}

	return rtn;
}

/**
 * Get pixel value
 *
 * @param band : the band to set nodata value to
 * @param x : x ordinate (0-based)
 * @param y : x ordinate (0-based)
 * @param *result: result if there is a value
 *
 * @return 0 on success, -1 on error (value out of valid range).
 */
int
rt_band_get_pixel(
	rt_band band,
	int x, int y,
	double *result
) {
    rt_pixtype pixtype = PT_END;
    uint8_t* data = NULL;
    uint32_t offset = 0;

    assert(NULL != band);

    pixtype = band->pixtype;

    if (
			x < 0 || x >= band->width ||
			y < 0 || y >= band->height
		) {
        rtwarn("Attempting to get pixel value with out of range raster coordinates: (%d, %d)", x, y);
        return -1;
    }

    data = rt_band_get_data(band);
		if (data == NULL) {
			rterror("rt_band_get_pixel: Cannot get band data");
			return -1;
		}

    offset = x + (y * band->width); /* +1 for the nodata value */

    switch (pixtype) {
        case PT_1BB:
#ifdef OPTIMIZE_SPACE
        {
            int byteOffset = offset / 8;
            int bitOffset = offset % 8;
            data += byteOffset;

            /* Bit to set is bitOffset into data */
            *result = getBits(data, val, 1, bitOffset);
            return 0;
        }
#endif

        case PT_2BUI:
#ifdef OPTIMIZE_SPACE
        {
            int byteOffset = offset / 4;
            int bitOffset = offset % 4;
            data += byteOffset;

            /* Bits to set start at bitOffset into data */
            *result = getBits(data, val, 2, bitOffset);
            return 0;
        }
#endif

        case PT_4BUI:
#ifdef OPTIMIZE_SPACE
        {
            int byteOffset = offset / 2;
            int bitOffset = offset % 2;
            data += byteOffset;

            /* Bits to set start at bitOffset into data */
            *result = getBits(data, val, 2, bitOffset);
            return 0;
        }
#endif

        case PT_8BSI:
        {
            int8_t val = data[offset];
            *result = val;
            return 0;
        }
        case PT_8BUI:
        {
            uint8_t val = data[offset];
            *result = val;
            return 0;
        }
        case PT_16BSI:
        {
            int16_t *ptr = (int16_t*) data; /* we assume correct alignment */
            *result = ptr[offset];
            return 0;
        }
        case PT_16BUI:
        {
            uint16_t *ptr = (uint16_t*) data; /* we assume correct alignment */
            *result = ptr[offset];
            return 0;
        }
        case PT_32BSI:
        {
            int32_t *ptr = (int32_t*) data; /* we assume correct alignment */
            *result = ptr[offset];
            return 0;
        }
        case PT_32BUI:
        {
            uint32_t *ptr = (uint32_t*) data; /* we assume correct alignment */
            *result = ptr[offset];
            return 0;
        }
        case PT_32BF:
        {
            float *ptr = (float*) data; /* we assume correct alignment */
            *result = ptr[offset];
            return 0;
        }
        case PT_64BF:
        {
            double *ptr = (double*) data; /* we assume correct alignment */
            *result = ptr[offset];
            return 0;
        }
        default:
        {
            rterror("rt_band_get_pixel: Unknown pixeltype %d", pixtype);
            return -1;
        }
    }
}

/**
 * Get nearest pixel(s) with value (not NODATA) to specified pixel
 *
 * @param band: the band to get nearest pixel(s) from
 * @param x: the column of the pixel (0-based)
 * @param y: the line of the pixel (0-based)
 * @param distance: the number of pixels around the specified pixel
 * @param exclude_nodata_value: if non-zero, ignore nodata values
 * to check for pixels with value
 * @param npixels: return set of rt_pixel object or NULL
 *
 * @return -1 on error, otherwise the number of rt_pixel objects
 * in npixels
 */
int rt_band_get_nearest_pixel(
	rt_band band,
	int x, int y,
	uint16_t distance,
	int exclude_nodata_value,
	rt_pixel *npixels
) {
	rt_pixel npixel = NULL;
	int extent[4] = {0};
	int d0 = 0;
	uint32_t _distance;
	uint32_t i = 0;
	uint32_t j = 0;
	uint32_t k = 0;
	uint32_t max = 0;
	int _x = 0;
	int _y = 0;
	int *_inc = NULL;
	double pixval = 0;
	double minval = 0;
	uint32_t count = 0;

	assert(NULL != band);
	assert(NULL != npixels);

	RASTER_DEBUG(3, "Starting");

	minval = rt_pixtype_get_min_value(band->pixtype);

	if (!distance)
		d0 = 1;

	RASTER_DEBUGF(4, "Selected pixel: %d x %d", x, y);
	RASTER_DEBUGF(4, "Distance: %d", distance);

	/* shortcuts if outside band extent */
	if (
		exclude_nodata_value && (
			(x < 0 || x > band->width) ||
			(y < 0 || y > band->height)
		)
	) {
		/* no distance specified, jump to pixel close to extent */
		if (!distance) {
			if (x < 0)
				x = -1;
			else if (x > band->width)
				x = band->width;

			if (y < 0)
				y = -1;
			else if (y > band->height)
				y = band->height;

			RASTER_DEBUGF(4, "Moved selected pixel: %d x %d", x, y);
		}
		/*
			distance specified
			if distance won't capture extent of band, return 0
		*/
		else if (
			((x < 0 && abs(x) > distance) || (x - band->width >= distance)) ||
			((x < 0 && abs(y) > distance) || (y - band->height >= distance))
		) {
			RASTER_DEBUG(4, "No nearest pixels possible for provided pixel and distance");
			return 0;
		}
	}

	/* determine the maximum distance to prevent an infinite loop */
	if (!distance) {
		int a, b;
		a = abs(x);
		b = abs(x - band->width);

		if (a > b)
			distance = a;
		else
			distance = b;

		a = abs(y);
		b = abs(y - band->height);
		if (a > distance)
			distance = a;
		if (b > distance)
			distance = b;

		RASTER_DEBUGF(4, "Maximum distance: %d", distance);
	}

	count = 0;
	_distance = 0;
	*npixels = NULL;
	do {
		_distance++;
		extent[0] = x - _distance; /* min x */
		extent[1] = y - _distance; /* min y */
		extent[2] = x + _distance; /* max x */
		extent[3] = y + _distance; /* max y */

		RASTER_DEBUGF(4, "Processing distance: %d", _distance);
		RASTER_DEBUGF(4, "Extent: (%d, %d, %d, %d)",
			extent[0], extent[1], extent[2], extent[3]);

		for (i = 0; i < 2; i++) {

			/* by row */
			if (i < 1)
				max = extent[2] - extent[0] + 1;
			/* by column */
			else
				max = extent[3] - extent[1] + 1;
			max = abs(max);

			for (j = 0; j < 2; j++) {
				/* by row */
				if (i < 1) {
					_x = extent[0];
					_inc = &_x;

					/* top row */
					if (j < 1)
						_y = extent[1];
					/* bottom row */
					else
						_y = extent[3];
				}
				/* by column */
				else {
					_y = extent[1] + 1;
					_inc = &_y;

					/* left column */
					if (j < 1) {
						_x = extent[0];
						max -= 2;
					}
					/* right column */
					else
						_x = extent[2];
				}

				RASTER_DEBUGF(4, "max: %d", max);
				for (k = 0; k < max; k++) {
					/* outside band extent, set to NODATA */
					if (
						(_x < 0 || _x >= band->width) ||
						(_y < 0 || _y >= band->height)
					) {
						/* no NODATA, set to minimum possible value */
						if (!band->hasnodata)
							pixval = minval;
						/* has NODATA, use NODATA */
						else
							pixval = band->nodataval;
						RASTER_DEBUGF(4, "NODATA pixel outside band extent: (x, y, val) = (%d, %d, %f)", _x, _y, pixval);
					}
					else {
						if (rt_band_get_pixel(
							band,
							_x, _y,
							&pixval
						) < 0) {
							rterror("rt_band_get_nearest_pixel: Unable to get pixel value");
							if (count) rtdealloc(*npixels);
							return -1;
						}
						RASTER_DEBUGF(4, "Pixel: (x, y, val) = (%d, %d, %f)", _x, _y, pixval);
					}

					/* use pixval? */
					if (
						!exclude_nodata_value || (
							exclude_nodata_value &&
							(band->hasnodata != FALSE) && (
								FLT_NEQ(pixval, band->nodataval) &&
								(rt_band_clamped_value_is_nodata(band, pixval) != 1)
							)
						)
					) {
						/* add pixel to result set */
						RASTER_DEBUGF(4, "Adding pixel to set of nearest pixels: (x, y, val) = (%d, %d, %f)", _x, _y, pixval);
						count++;

						if (*npixels == NULL)
							*npixels = (rt_pixel) rtalloc(sizeof(struct rt_pixel_t) * count);
						else
							*npixels = (rt_pixel) rtrealloc(*npixels, sizeof(struct rt_pixel_t) * count);
						if (*npixels == NULL) {
							rterror("rt_band_get_nearest_pixel: Unable to allocate memory for nearest pixel(s)");
							return -1;
						}

						npixel = &((*npixels)[count - 1]);
						npixel->x = _x;
						npixel->y = _y;
						npixel->nodata = 0;
						npixel->value = pixval;
					}

					(*_inc)++;
				}
			}
		}

		/* distance threshhold met */
		if (_distance >= distance)
			break;
		else if (d0 && count)
			break;
	}
	while (1);

	RASTER_DEBUGF(3, "Nearest pixels in return: %d", count);

	return count;
}

double
rt_band_get_nodata(rt_band band) {


    assert(NULL != band);

    if (!band->hasnodata)
        RASTER_DEBUGF(3, "Getting nodata value for a band without NODATA values. Using %g", band->nodataval);


    return band->nodataval;
}

double
rt_band_get_min_value(rt_band band) {
	assert(NULL != band);

	return rt_pixtype_get_min_value(band->pixtype);
}


int
rt_band_check_is_nodata(rt_band band) {
	int i, j, err;
	double pxValue;

	assert(NULL != band);

	/* Check if band has nodata value */
	if (!band->hasnodata) {
		RASTER_DEBUG(3, "Band has no NODATA value");
		band->isnodata = FALSE;
		return FALSE;
	}

	pxValue = band->nodataval;

	/* Check all pixels */
	for (i = 0; i < band->width; i++) {
		for (j = 0; j < band->height; j++) {
			err = rt_band_get_pixel(band, i, j, &pxValue);
			if (err != 0) {
				rterror("rt_band_check_is_nodata: Cannot get band pixel");
				return FALSE;
			}
			else if (FLT_NEQ(pxValue, band->nodataval)) {
				band->isnodata = FALSE;
				return FALSE;
			}
		}
	}

	band->isnodata = TRUE;
	return TRUE;
}

/**
 * Compare clamped value to band's clamped NODATA value.  If unclamped
 * value is exactly unclamped NODATA value, function returns -1.
 *
 * @param band: the band whose NODATA value will be used for comparison
 * @param val: the value to compare to the NODATA value
 *
 * @return 1 if clamped value is clamped NODATA
 *         0 if clamped value is NOT clamped NODATA
 *         -1 otherwise
 */
int
rt_band_clamped_value_is_nodata(rt_band band, double val) {

	assert(NULL != band);

	/* no NODATA, so no need to test */
	if (!band->hasnodata)
		return -1;

	/* value is exactly NODATA */
	if (FLT_EQ(val, band->nodataval))
		return -1;

	switch (band->pixtype) {
		case PT_1BB:
			if (rt_util_clamp_to_1BB(val) == rt_util_clamp_to_1BB(band->nodataval))
				return 1;
			break;
		case PT_2BUI:
			if (rt_util_clamp_to_2BUI(val) == rt_util_clamp_to_2BUI(band->nodataval))
				return 1;
			break;
		case PT_4BUI:
			if (rt_util_clamp_to_4BUI(val) == rt_util_clamp_to_4BUI(band->nodataval))
				return 1;
			break;
		case PT_8BSI:
			if (rt_util_clamp_to_8BSI(val) == rt_util_clamp_to_8BSI(band->nodataval))
				return 1;
			break;
		case PT_8BUI:
			if (rt_util_clamp_to_8BUI(val) == rt_util_clamp_to_8BUI(band->nodataval))
				return 1;
			break;
		case PT_16BSI:
			if (rt_util_clamp_to_16BSI(val) == rt_util_clamp_to_16BSI(band->nodataval))
				return 1;
			break;
		case PT_16BUI:
			if (rt_util_clamp_to_16BUI(val) == rt_util_clamp_to_16BUI(band->nodataval))
				return 1;
			break;
		case PT_32BSI:
			if (rt_util_clamp_to_32BSI(val) == rt_util_clamp_to_32BSI(band->nodataval))
				return 1;
			break;
		case PT_32BUI:
			if (rt_util_clamp_to_32BUI(val) == rt_util_clamp_to_32BUI(band->nodataval))
				return 1;
			break;
		case PT_32BF:
			if (FLT_EQ(rt_util_clamp_to_32F(val), rt_util_clamp_to_32F(band->nodataval)))
				return 1;
			break;
		case PT_64BF:
			break;
		default:
			rterror("rt_band_clamped_value_is_nodata: Unknown pixeltype %d", band->pixtype);
			return -1;
	}

	return 0;
}

/**
 * Correct value when clamped value is clamped NODATA value.  Correction
 * does NOT occur if unclamped value is exactly unclamped NODATA value.
 * 
 * @param band: the band whose NODATA value will be used for comparison
 * @param val: the value to compare to the NODATA value and correct
 * @param newval: pointer to corrected value
 *
 * @return 0 on error, 1 if corrected, -1 otherwise
 */
int
rt_band_corrected_clamped_value(rt_band band, double val, double *newval) {
	double minval = 0.;

	assert(NULL != band);

	/* check that value needs correcting */
	if (rt_band_clamped_value_is_nodata(band, val) != 1) {
		*newval = val;
		return -1;
	}

	minval = rt_pixtype_get_min_value(band->pixtype);
	*newval = val;

	switch (band->pixtype) {
		case PT_1BB:
			*newval = !band->nodataval;
			break;
		case PT_2BUI:
			if (rt_util_clamp_to_2BUI(val) == rt_util_clamp_to_2BUI(minval))
				(*newval)++;
			else
				(*newval)--;
			break;
		case PT_4BUI:
			if (rt_util_clamp_to_4BUI(val) == rt_util_clamp_to_4BUI(minval))
				(*newval)++;
			else
				(*newval)--;
			break;
		case PT_8BSI:
			if (rt_util_clamp_to_8BSI(val) == rt_util_clamp_to_8BSI(minval))
				(*newval)++;
			else
				(*newval)--;
			break;
		case PT_8BUI:
			if (rt_util_clamp_to_8BUI(val) == rt_util_clamp_to_8BUI(minval))
				(*newval)++;
			else
				(*newval)--;
			break;
		case PT_16BSI:
			if (rt_util_clamp_to_16BSI(val) == rt_util_clamp_to_16BSI(minval))
				(*newval)++;
			else
				(*newval)--;
			break;
		case PT_16BUI:
			if (rt_util_clamp_to_16BUI(val) == rt_util_clamp_to_16BUI(minval))
				(*newval)++;
			else
				(*newval)--;
			break;
		case PT_32BSI:
			if (rt_util_clamp_to_32BSI(val) == rt_util_clamp_to_32BSI(minval))
				(*newval)++;
			else
				(*newval)--;
			break;
		case PT_32BUI:
			if (rt_util_clamp_to_32BUI(val) == rt_util_clamp_to_32BUI(minval))
				(*newval)++;
			else
				(*newval)--;
			break;
		case PT_32BF:
			if (FLT_EQ(rt_util_clamp_to_32F(val), rt_util_clamp_to_32F(minval)))
				*newval += FLT_EPSILON;
			else
				*newval -= FLT_EPSILON;
			break;
		case PT_64BF:
			break;
		default:
			rterror("rt_band_alternative_clamped_value: Unknown pixeltype %d", band->pixtype);
			return 0;
	}

	return 1;
}

/**
 * Compute summary statistics for a band
 *
 * @param band: the band to query for summary stats
 * @param exclude_nodata_value: if non-zero, ignore nodata values
 * @param sample: percentage of pixels to sample
 * @param inc_vals: flag to include values in return struct
 * @param cK: number of pixels counted thus far in coverage
 * @param cM: M component of 1-pass stddev for coverage
 * @param cQ: Q component of 1-pass stddev for coverage
 *
 * @return the summary statistics for a band
 */
rt_bandstats
rt_band_get_summary_stats(rt_band band, int exclude_nodata_value, double sample,
	int inc_vals, uint64_t *cK, double *cM, double *cQ) {
	uint8_t *data = NULL;
	uint32_t x = 0;
	uint32_t y = 0;
	uint32_t z = 0;
	uint32_t offset = 0;
	uint32_t diff = 0;
	int rtn;
	int hasnodata = FALSE;
	double nodata = 0;
	double *values = NULL;
	double value;
	rt_bandstats stats = NULL;

	uint32_t do_sample = 0;
	uint32_t sample_size = 0;
	uint32_t sample_per = 0;
	uint32_t sample_int = 0;
	uint32_t i = 0;
	uint32_t j = 0;
	double sum = 0;
	uint32_t k = 0;
	double M = 0;
	double Q = 0;

#if POSTGIS_DEBUG_LEVEL > 0
	clock_t start, stop;
	double elapsed = 0;
#endif

	RASTER_DEBUG(3, "starting");
#if POSTGIS_DEBUG_LEVEL > 0
	start = clock();
#endif

	assert(NULL != band);

	data = rt_band_get_data(band);
	if (data == NULL) {
		rterror("rt_band_get_summary_stats: Cannot get band data");
		return NULL;
	}

	hasnodata = rt_band_get_hasnodata_flag(band);
	if (hasnodata != FALSE)
		nodata = rt_band_get_nodata(band);
	else
		exclude_nodata_value = 0;

	RASTER_DEBUGF(3, "nodata = %f", nodata);
	RASTER_DEBUGF(3, "hasnodata = %d", hasnodata);
	RASTER_DEBUGF(3, "exclude_nodata_value = %d", exclude_nodata_value);

	/* entire band is nodata */
	if (rt_band_get_isnodata_flag(band) != FALSE) {
		stats = (rt_bandstats) rtalloc(sizeof(struct rt_bandstats_t));
		if (NULL == stats) {
			rterror("rt_band_get_summary_stats: Unable to allocate memory for stats");
			return NULL;
		}

		stats->sample = 1;
		stats->sorted = 0;
		stats->values = NULL;

		if (exclude_nodata_value) {
			rtwarn("All pixels of band have the NODATA value");

			stats->count = 0;
			stats->min = stats->max = 0;
			stats->sum = 0;
			stats->mean = 0;
			stats->stddev = -1;
		}
		else {
			stats->count = band->width * band->height;
			stats->min = stats->max = nodata;
			stats->sum = stats->count * nodata;
			stats->mean = nodata;
			stats->stddev = 0;
		}

		return stats;
	}

	/* clamp percentage */
	if (
		(sample < 0 || FLT_EQ(sample, 0.0)) ||
		(sample > 1 || FLT_EQ(sample, 1.0))
	) {
		do_sample = 0;
		sample = 1;
	}
	else
		do_sample = 1;
	RASTER_DEBUGF(3, "do_sample = %d", do_sample);

	/* sample all pixels */
	if (!do_sample) {
		sample_size = band->width * band->height;
		sample_per = band->height;
	}
	/*
	 randomly sample a percentage of available pixels
	 sampling method is known as
	 	"systematic random sample without replacement"
	*/
	else {
		sample_size = round((band->width * band->height) * sample);
		sample_per = round(sample_size / band->width);
		sample_int = round(band->height / sample_per);
		srand(time(NULL));
	}

	RASTER_DEBUGF(3, "sampling %d of %d available pixels w/ %d per set"
		, sample_size, (band->width * band->height), sample_per);

	if (inc_vals) {
		values = rtalloc(sizeof(double) * sample_size);
		if (NULL == values) {
			rtwarn("Unable to allocate memory for values");
			inc_vals = 0;
		}
	}

	/* initialize stats */
	stats = (rt_bandstats) rtalloc(sizeof(struct rt_bandstats_t));
	if (NULL == stats) {
		rterror("rt_band_get_summary_stats: Unable to allocate memory for stats");
		return NULL;
	}
	stats->sample = sample;
	stats->count = 0;
	stats->sum = 0;
	stats->mean = 0;
	stats->stddev = -1;
	stats->min = stats->max = 0;
	stats->values = NULL;
	stats->sorted = 0;

	for (x = 0, j = 0, k = 0; x < band->width; x++) {
		y = -1;
		diff = 0;

		for (i = 0, z = 0; i < sample_per; i++) {
			if (!do_sample)
				y = i;
			else {
				offset = (rand() % sample_int) + 1;
				y += diff + offset;
				diff = sample_int - offset;
			}
			RASTER_DEBUGF(5, "(x, y, z) = (%d, %d, %d)", x, y, z);
			if (y >= band->height || z > sample_per) break;

			rtn = rt_band_get_pixel(band, x, y, &value);
#if POSTGIS_DEBUG_LEVEL > 0
			if (rtn != -1) {
				RASTER_DEBUGF(5, "(x, y, value) = (%d,%d, %f)", x, y, value);
			}
#endif

			j++;
			if (
				rtn != -1 && (
					!exclude_nodata_value || (
						exclude_nodata_value &&
						(hasnodata != FALSE) && (
							FLT_NEQ(value, nodata) &&
							(rt_band_clamped_value_is_nodata(band, value) != 1)
						)
					)
				)
			) {

				/* inc_vals set, collect pixel values */
				if (inc_vals) values[k] = value;

				/* average */
				k++;
				sum += value;

				/*
					one-pass standard deviation
					http://www.eecs.berkeley.edu/~mhoemmen/cs194/Tutorials/variance.pdf
				*/
				if (k == 1) {
					Q = 0;
					M = value;
				}
				else {
					Q += (((k  - 1) * pow(value - M, 2)) / k);
					M += ((value - M ) / k);
				}

				/* coverage one-pass standard deviation */
				if (NULL != cK) {
					(*cK)++;
					if (*cK == 1) {
						*cQ = 0;
						*cM = value;
					}
					else {
						*cQ += (((*cK  - 1) * pow(value - *cM, 2)) / *cK);
						*cM += ((value - *cM ) / *cK);
					}
				}

				/* min/max */
				if (stats->count < 1) {
					stats->count = 1;
					stats->min = stats->max = value;
				}
				else {
					if (value < stats->min)
						stats->min = value;
					if (value > stats->max)
						stats->max = value;
				}

			}

			z++;
		}
	}

	RASTER_DEBUG(3, "sampling complete");

	stats->count = k;
	if (k > 0) {
		if (inc_vals) {
			/* free unused memory */
			if (sample_size != k) {
				values = rtrealloc(values, k * sizeof(double));
			}

			stats->values = values;
		}

		stats->sum = sum;
		stats->mean = sum / k;

		/* standard deviation */
		if (!do_sample)
			stats->stddev = sqrt(Q / k);
		/* sample deviation */
		else {
			if (k < 2)
				stats->stddev = -1;
			else
				stats->stddev = sqrt(Q / (k - 1));
		}
	}
	/* inc_vals thus values allocated but not used */
	else if (inc_vals)
		rtdealloc(values);

	/* if count is zero and do_sample is one */
	if (k < 0 && do_sample)
		rtwarn("All sampled pixels of band have the NODATA value");

#if POSTGIS_DEBUG_LEVEL > 0
	stop = clock();
	elapsed = ((double) (stop - start)) / CLOCKS_PER_SEC;
	RASTER_DEBUGF(3, "(time, count, mean, stddev, min, max) = (%0.4f, %d, %f, %f, %f, %f)",
		elapsed, stats->count, stats->mean, stats->stddev, stats->min, stats->max);
#endif

	RASTER_DEBUG(3, "done");
	return stats;
}

/**
 * Count the distribution of data
 *
 * @param stats: a populated stats struct for processing
 * @param bin_count: the number of bins to group the data by
 * @param bin_width: the width of each bin as an array
 * @param bin_width_count: number of values in bin_width
 * @param right: evaluate bins by (a,b] rather than default [a,b)
 * @param min: user-defined minimum value of the histogram
 *   a value less than the minimum value is not counted in any bins
 *   if min = max, min and max are not used
 * @param max: user-defined maximum value of the histogram
 *   a value greater than the max value is not counted in any bins
 *   if min = max, min and max are not used
 * @param rtn_count: set to the number of bins being returned
 *
 * @return the histogram of the data
 */
rt_histogram
rt_band_get_histogram(rt_bandstats stats,
	int bin_count, double *bin_width, int bin_width_count,
	int right, double min, double max, uint32_t *rtn_count) {
	rt_histogram bins = NULL;
	int init_width = 0;
	int i;
	int j;
	double tmp;
	double value;
	int sum = 0;
	int user_minmax = 0;
	double qmin;
	double qmax;

#if POSTGIS_DEBUG_LEVEL > 0
	clock_t start, stop;
	double elapsed = 0;
#endif

	RASTER_DEBUG(3, "starting");
#if POSTGIS_DEBUG_LEVEL > 0
	start = clock();
#endif

	assert(NULL != stats);

	if (stats->count < 1 || NULL == stats->values) {
		rterror("rt_util_get_histogram: rt_bandstats object has no value");
		return NULL;
	}

	/* bin width must be positive numbers and not zero */
	if (NULL != bin_width && bin_width_count > 0) {
		for (i = 0; i < bin_width_count; i++) {
			if (bin_width[i] < 0 || FLT_EQ(bin_width[i], 0.0)) {
				rterror("rt_util_get_histogram: bin_width element is less than or equal to zero");
				return NULL;
			}
		}
	}

	/* ignore min and max parameters */
	if (FLT_EQ(max, min)) {
		qmin = stats->min;
		qmax = stats->max;
	}
	else {
		user_minmax = 1;
		qmin = min;
		qmax = max;
		if (qmin > qmax) {
			qmin = max;
			qmax = min;
		}
	}

	/* # of bins not provided */
	if (bin_count <= 0) {
		/*
			determine # of bins
			http://en.wikipedia.org/wiki/Histogram

			all computed bins are assumed to have equal width
		*/
		/* Square-root choice for stats->count < 30 */
		if (stats->count < 30)
			bin_count = ceil(sqrt(stats->count));
		/* Sturges' formula for stats->count >= 30 */
		else
			bin_count = ceil(log2((double) stats->count) + 1.);

		/* bin_width_count provided and bin_width has value */
		if (bin_width_count > 0 && NULL != bin_width) {
			/* user has defined something specific */
			if (bin_width_count > bin_count)
				bin_count = bin_width_count;
			else if (bin_width_count > 1) {
				tmp = 0;
				for (i = 0; i < bin_width_count; i++) tmp += bin_width[i];
				bin_count = ceil((qmax - qmin) / tmp) * bin_width_count;
			}
			else
				bin_count = ceil((qmax - qmin) / bin_width[0]);
		}
		/* set bin width count to zero so that one can be calculated */
		else {
			bin_width_count = 0;
		}
	}

	/* min and max the same */
	if (FLT_EQ(qmax, qmin)) bin_count = 1;

	RASTER_DEBUGF(3, "bin_count = %d", bin_count);

	/* bin count = 1, all values are in one bin */
	if (bin_count < 2) {
		bins = rtalloc(sizeof(struct rt_histogram_t));
		if (NULL == bins) {
			rterror("rt_util_get_histogram: Unable to allocate memory for histogram");
			return NULL;
		}

		bins->count = stats->count;
		bins->percent = -1;
		bins->min = qmin;
		bins->max = qmax;
		bins->inc_min = bins->inc_max = 1;

		*rtn_count = bin_count;
		return bins;
	}

	/* establish bin width */
	if (bin_width_count == 0) {
		bin_width_count = 1;

		/* bin_width unallocated */
		if (NULL == bin_width) {
			bin_width = rtalloc(sizeof(double));
			if (NULL == bin_width) {
				rterror("rt_util_get_histogram: Unable to allocate memory for bin widths");
				return NULL;
			}
			init_width = 1;
		}

		bin_width[0] = (qmax - qmin) / bin_count;
	}

	/* initialize bins */
	bins = rtalloc(bin_count * sizeof(struct rt_histogram_t));
	if (NULL == bins) {
		rterror("rt_util_get_histogram: Unable to allocate memory for histogram");
		if (init_width) rtdealloc(bin_width);
		return NULL;
	}
	if (!right)
		tmp = qmin;
	else
		tmp = qmax;
	for (i = 0; i < bin_count;) {
		for (j = 0; j < bin_width_count; j++) {
			bins[i].count = 0;
			bins->percent = -1;

			if (!right) {
				bins[i].min = tmp;
				tmp += bin_width[j];
				bins[i].max = tmp;

				bins[i].inc_min = 1;
				bins[i].inc_max = 0;
			}
			else {
				bins[i].max = tmp;
				tmp -= bin_width[j];
				bins[i].min = tmp;

				bins[i].inc_min = 0;
				bins[i].inc_max = 1;
			}

			i++;
		}
	}
	if (!right) {
		bins[bin_count - 1].inc_max = 1;

		/* align last bin to the max value */
		if (bins[bin_count - 1].max < qmax)
			bins[bin_count - 1].max = qmax;
	}
	else {
		bins[bin_count - 1].inc_min = 1;

		/* align first bin to the min value */
		if (bins[bin_count - 1].min > qmin)
			bins[bin_count - 1].min = qmin;
	}

	/* process the values */
	for (i = 0; i < stats->count; i++) {
		value = stats->values[i];

		/* default, [a, b) */
		if (!right) {
			for (j = 0; j < bin_count; j++) {
				if (
					(!bins[j].inc_max && value < bins[j].max) || (
						bins[j].inc_max && (
							(value < bins[j].max) ||
							FLT_EQ(value, bins[j].max)
						)
					)
				) {
					bins[j].count++;
					sum++;
					break;
				}
			}
		}
		/* (a, b] */
		else {
			for (j = 0; j < bin_count; j++) {
				if (
					(!bins[j].inc_min && value > bins[j].min) || (
						bins[j].inc_min && (
							(value > bins[j].min) ||
							FLT_EQ(value, bins[j].min)
						)
					)
				) {
					bins[j].count++;
					sum++;
					break;
				}
			}
		}
	}

	for (i = 0; i < bin_count; i++) {
		bins[i].percent = ((double) bins[i].count) / sum;
	}

#if POSTGIS_DEBUG_LEVEL > 0
	stop = clock();
	elapsed = ((double) (stop - start)) / CLOCKS_PER_SEC;
	RASTER_DEBUGF(3, "elapsed time = %0.4f", elapsed);

	for (j = 0; j < bin_count; j++) {
		RASTER_DEBUGF(5, "(min, max, inc_min, inc_max, count, sum, percent) = (%f, %f, %d, %d, %d, %d, %f)",
			bins[j].min, bins[j].max, bins[j].inc_min, bins[j].inc_max, bins[j].count, sum, bins[j].percent);
	}
#endif

	if (init_width) rtdealloc(bin_width);
	*rtn_count = bin_count;
	RASTER_DEBUG(3, "done");
	return bins;
}

/**
 * Compute the default set of or requested quantiles for a set of data
 * the quantile formula used is same as Excel and R default method
 *
 * @param stats: a populated stats struct for processing
 * @param quantiles: the quantiles to be computed
 * @param quantiles_count: the number of quantiles to be computed
 * @param rtn_count: set to the number of quantiles being returned
 *
 * @return the default set of or requested quantiles for a band
 */
rt_quantile
rt_band_get_quantiles(rt_bandstats stats,
	double *quantiles, int quantiles_count, uint32_t *rtn_count) {
	rt_quantile rtn;
	int init_quantiles = 0;
	int i = 0;
	double h;
	int hl;

#if POSTGIS_DEBUG_LEVEL > 0
	clock_t start, stop;
	double elapsed = 0;
#endif

	RASTER_DEBUG(3, "starting");
#if POSTGIS_DEBUG_LEVEL > 0
	start = clock();
#endif

	assert(NULL != stats);

	if (stats->count < 1 || NULL == stats->values) {
		rterror("rt_band_get_quantiles: rt_bandstats object has no value");
		return NULL;
	}

	/* quantiles not provided */
	if (NULL == quantiles) {
		/* quantile count not specified, default to quartiles */
		if (quantiles_count < 2)
			quantiles_count = 5;

		quantiles = rtalloc(sizeof(double) * quantiles_count);
		init_quantiles = 1;
		if (NULL == quantiles) {
			rterror("rt_band_get_quantiles: Unable to allocate memory for quantile input");
			return NULL;
		}

		quantiles_count--;
		for (i = 0; i <= quantiles_count; i++)
			quantiles[i] = ((double) i) / quantiles_count;
		quantiles_count++;
	}

	/* check quantiles */
	for (i = 0; i < quantiles_count; i++) {
		if (quantiles[i] < 0. || quantiles[i] > 1.) {
			rterror("rt_band_get_quantiles: Quantile value not between 0 and 1");
			if (init_quantiles) rtdealloc(quantiles);
			return NULL;
		}
	}
	quicksort(quantiles, quantiles + quantiles_count - 1);

	/* initialize rt_quantile */
	rtn = rtalloc(sizeof(struct rt_quantile_t) * quantiles_count);
	if (NULL == rtn) {
		rterror("rt_band_get_quantiles: Unable to allocate memory for quantile output");
		if (init_quantiles) rtdealloc(quantiles);
		return NULL;
	}

	/* sort values */
	if (!stats->sorted) {
		quicksort(stats->values, stats->values + stats->count - 1);
		stats->sorted = 1;
	}

	/*
		make quantiles

		formula is that used in R (method 7) and Excel from
			http://en.wikipedia.org/wiki/Quantile
	*/
	for (i = 0; i < quantiles_count; i++) {
		rtn[i].quantile = quantiles[i];

		h = ((stats->count - 1.) * quantiles[i]) + 1.;
		hl = floor(h);

		/* h greater than hl, do full equation */
		if (h > hl)
			rtn[i].value = stats->values[hl - 1] + ((h - hl) * (stats->values[hl] - stats->values[hl - 1]));
		/* shortcut as second part of equation is zero */
		else
			rtn[i].value = stats->values[hl - 1];
	}

#if POSTGIS_DEBUG_LEVEL > 0
	stop = clock();
	elapsed = ((double) (stop - start)) / CLOCKS_PER_SEC;
	RASTER_DEBUGF(3, "elapsed time = %0.4f", elapsed);
#endif

	*rtn_count = quantiles_count;
	if (init_quantiles) rtdealloc(quantiles);
	RASTER_DEBUG(3, "done");
	return rtn;
}

static struct quantile_llist_element *quantile_llist_search(
	struct quantile_llist_element *element,
	double needle
) {
	if (NULL == element)
		return NULL;
	else if (FLT_NEQ(needle, element->value)) {
		if (NULL != element->next)
			return quantile_llist_search(element->next, needle);
		else
			return NULL;
	}
	else
		return element;
}

static struct quantile_llist_element *quantile_llist_insert(
	struct quantile_llist_element *element,
	double value,
	uint32_t *idx
) {
	struct quantile_llist_element *qle = NULL;

	if (NULL == element) {
		qle = rtalloc(sizeof(struct quantile_llist_element));
		RASTER_DEBUGF(4, "qle @ %p is only element in list", qle);
		if (NULL == qle) return NULL;

		qle->value = value;
		qle->count = 1;

		qle->prev = NULL;
		qle->next = NULL;

		if (NULL != idx) *idx = 0;
		return qle;
	}
	else if (value > element->value) {
		if (NULL != idx) *idx += 1;
		if (NULL != element->next)
			return quantile_llist_insert(element->next, value, idx);
		/* insert as last element in list */
		else {
			qle = rtalloc(sizeof(struct quantile_llist_element));
			RASTER_DEBUGF(4, "insert qle @ %p as last element", qle);
			if (NULL == qle) return NULL;

			qle->value = value;
			qle->count = 1;

			qle->prev = element;
			qle->next = NULL;
			element->next = qle;

			return qle;
		}
	}
	/* insert before current element */
	else {
		qle = rtalloc(sizeof(struct quantile_llist_element));
		RASTER_DEBUGF(4, "insert qle @ %p before current element", qle);
		if (NULL == qle) return NULL;

		qle->value = value;
		qle->count = 1;

		if (NULL != element->prev) element->prev->next = qle;
		qle->next = element;
		qle->prev = element->prev;
		element->prev = qle;

		return qle;
	}
}

static int quantile_llist_delete(struct quantile_llist_element *element) {
	if (NULL == element) return 0;

	/* beginning of list */
	if (NULL == element->prev && NULL != element->next) {
		element->next->prev = NULL;
	}
	/* end of list */
	else if (NULL != element->prev && NULL == element->next) {
		element->prev->next = NULL;
	}
	/* within list */
	else if (NULL != element->prev && NULL != element->next) {
		element->prev->next = element->next;
		element->next->prev = element->prev;
	}

	RASTER_DEBUGF(4, "qle @ %p destroyed", element);
	rtdealloc(element);

	return 1;
}

int quantile_llist_destroy(struct quantile_llist **list, uint32_t list_count) {
	struct quantile_llist_element *element = NULL;
	uint32_t i;

	if (NULL == *list) return 0;

	for (i = 0; i < list_count; i++) {
		element = (*list)[i].head;
		while (NULL != element->next) {
			quantile_llist_delete(element->next);
		}
		quantile_llist_delete(element);

		rtdealloc((*list)[i].index);
	}

	rtdealloc(*list);
	return 1;
}

static void quantile_llist_index_update(struct quantile_llist *qll, struct quantile_llist_element *qle, uint32_t idx) {
	uint32_t anchor = (uint32_t) floor(idx / 100);

	if (qll->tail == qle) return;

	if (
		(anchor != 0) && (
			NULL == qll->index[anchor].element ||
			idx <= qll->index[anchor].index
		)
	) {
		qll->index[anchor].index = idx;
		qll->index[anchor].element = qle;
	}

	if (anchor != 0 && NULL == qll->index[0].element) {
		qll->index[0].index = 0;
		qll->index[0].element = qll->head;
	}
}

static void quantile_llist_index_delete(struct quantile_llist *qll, struct quantile_llist_element *qle) {
	uint32_t i = 0;

	for (i = 0; i < qll->index_max; i++) {
		if (
			NULL == qll->index[i].element ||
			(qll->index[i].element) != qle
		) {
			continue;
		}

		RASTER_DEBUGF(5, "deleting index: %d => %f", i, qle->value);
		qll->index[i].index = -1;
		qll->index[i].element = NULL;
	}
}

static struct quantile_llist_element *quantile_llist_index_search(
	struct quantile_llist *qll,
	double value,
	uint32_t *index
) {
	uint32_t i = 0, j = 0;
	RASTER_DEBUGF(5, "searching index for value %f", value);

	for (i = 0; i < qll->index_max; i++) {
		if (NULL == qll->index[i].element) {
			if (i < 1) break;
			continue;
		}
		if (value > (qll->index[i]).element->value) continue;

		if (FLT_EQ(value, qll->index[i].element->value)) {
			RASTER_DEBUGF(5, "using index value at %d = %f", i, qll->index[i].element->value);
			*index = i * 100;
			return qll->index[i].element;
		}
		else if (i > 0) {
			for (j = 1; j < i; j++) {
				if (NULL != qll->index[i - j].element) {
					RASTER_DEBUGF(5, "using index value at %d = %f", i - j, qll->index[i - j].element->value);
					*index = (i - j) * 100;
					return qll->index[i - j].element;
				}
			}
		}
	}

	*index = 0;
	return qll->head;
}

static void quantile_llist_index_reset(struct quantile_llist *qll) {
	uint32_t i = 0;

	RASTER_DEBUG(5, "resetting index");
	for (i = 0; i < qll->index_max; i++) {
		qll->index[i].index = -1;
		qll->index[i].element = NULL;
	}
}

/**
 * Compute the default set of or requested quantiles for a coverage
 *
 * This function is based upon the algorithm described in:
 *
 * A One-Pass Space-Efficient Algorithm for Finding Quantiles (1995)
 *   by Rakesh Agrawal, Arun Swami
 *   in Proc. 7th Intl. Conf. Management of Data (COMAD-95)
 *
 * http://www.almaden.ibm.com/cs/projects/iis/hdb/Publications/papers/comad95.pdf
 *
 * In the future, it may be worth exploring algorithms that don't
 *   require the size of the coverage
 *
 * @param band: the band to include in the quantile search
 * @param exclude_nodata_value: if non-zero, ignore nodata values
 * @param sample: percentage of pixels to sample
 * @param cov_count: number of values in coverage
 * @param qlls: set of quantile_llist structures
 * @param qlls_count: the number of quantile_llist structures
 * @param quantiles: the quantiles to be computed
 *   if bot qlls and quantiles provided, qlls is used
 * @param quantiles_count: the number of quantiles to be computed
 * @param rtn_count: the number of quantiles being returned
 *
 * @return the default set of or requested quantiles for a band
 */
rt_quantile
rt_band_get_quantiles_stream(rt_band band,
	int exclude_nodata_value, double sample,
	uint64_t cov_count,
	struct quantile_llist **qlls, uint32_t *qlls_count,
	double *quantiles, int quantiles_count,
	uint32_t *rtn_count) {
	rt_quantile rtn = NULL;
	int init_quantiles = 0;

	struct quantile_llist *qll = NULL;
	struct quantile_llist_element *qle = NULL;
	struct quantile_llist_element *qls = NULL;
	const uint32_t MAX_VALUES = 750;

	uint8_t *data = NULL;
	int hasnodata = FALSE;
	double nodata = 0;
	double value;

	uint32_t a = 0;
	uint32_t i = 0;
	uint32_t j = 0;
	uint32_t k = 0;
	uint32_t x = 0;
	uint32_t y = 0;
	uint32_t z = 0;
	uint32_t idx = 0;
	uint32_t offset = 0;
	uint32_t diff = 0;
	uint8_t exists = 0;

	uint32_t do_sample = 0;
	uint32_t sample_size = 0;
	uint32_t sample_per = 0;
	uint32_t sample_int = 0;
	int status;

	RASTER_DEBUG(3, "starting");

	assert(NULL != band);
	assert(cov_count > 1);
	RASTER_DEBUGF(3, "cov_count = %d", cov_count);


	data = rt_band_get_data(band);
	if (data == NULL) {
		rterror("rt_band_get_summary_stats: Cannot get band data");
		return NULL;
	}

	hasnodata = rt_band_get_hasnodata_flag(band);
	if (hasnodata != FALSE)
		nodata = rt_band_get_nodata(band);
	else
		exclude_nodata_value = 0;
	RASTER_DEBUGF(3, "nodata = %f", nodata);
	RASTER_DEBUGF(3, "hasnodata = %d", hasnodata);
	RASTER_DEBUGF(3, "exclude_nodata_value = %d", exclude_nodata_value);

	/* quantile_llist not provided */
	if (NULL == *qlls) {
		/* quantiles not provided */
		if (NULL == quantiles) {
			/* quantile count not specified, default to quartiles */
			if (quantiles_count < 2)
				quantiles_count = 5;

			quantiles = rtalloc(sizeof(double) * quantiles_count);
			init_quantiles = 1;
			if (NULL == quantiles) {
				rterror("rt_band_get_quantiles_stream: Unable to allocate memory for quantile input");
				return NULL;
			}

			quantiles_count--;
			for (i = 0; i <= quantiles_count; i++)
				quantiles[i] = ((double) i) / quantiles_count;
			quantiles_count++;
		}

		/* check quantiles */
		for (i = 0; i < quantiles_count; i++) {
			if (quantiles[i] < 0. || quantiles[i] > 1.) {
				rterror("rt_band_get_quantiles_stream: Quantile value not between 0 and 1");
				if (init_quantiles) rtdealloc(quantiles);
				return NULL;
			}
		}
		quicksort(quantiles, quantiles + quantiles_count - 1);

		/* initialize linked-list set */
		*qlls_count = quantiles_count * 2;
		RASTER_DEBUGF(4, "qlls_count = %d", *qlls_count);
		*qlls = rtalloc(sizeof(struct quantile_llist) * *qlls_count);
		if (NULL == *qlls) {
			rterror("rt_band_get_quantiles_stream: Unable to allocate memory for quantile output");
			if (init_quantiles) rtdealloc(quantiles);
			return NULL;
		}

		j = (uint32_t) floor(MAX_VALUES / 100.) + 1;
		for (i = 0; i < *qlls_count; i++) {
			qll = &((*qlls)[i]);
			qll->quantile = quantiles[(i * quantiles_count) / *qlls_count];
			qll->count = 0;
			qll->sum1 = 0;
			qll->sum2 = 0;
			qll->head = NULL;
			qll->tail = NULL;

			/* initialize index */
			qll->index = rtalloc(sizeof(struct quantile_llist_index) * j);
			if (NULL == qll->index) {
				rterror("rt_band_get_quantiles_stream: Unable to allocate memory for quantile output");
				if (init_quantiles) rtdealloc(quantiles);
				return NULL;
			}
			qll->index_max = j;
			quantile_llist_index_reset(qll);

			/* AL-GEQ */
			if (!(i % 2)) {
				qll->algeq = 1;
				qll->tau = (uint64_t) ROUND(cov_count - (cov_count * qll->quantile), 0);
				if (qll->tau < 1) qll->tau = 1;
			}
			/* AL-GT */
			else {
				qll->algeq = 0;
				qll->tau = cov_count - (*qlls)[i - 1].tau + 1;
			}

			RASTER_DEBUGF(4, "qll init: (algeq, quantile, count, tau, sum1, sum2) = (%d, %f, %d, %d, %d, %d)",
				qll->algeq, qll->quantile, qll->count, qll->tau, qll->sum1, qll->sum2);
			RASTER_DEBUGF(4, "qll init: (head, tail) = (%p, %p)", qll->head, qll->tail);
		}

		if (init_quantiles) rtdealloc(quantiles);
	}

	/* clamp percentage */
	if (
		(sample < 0 || FLT_EQ(sample, 0.0)) ||
		(sample > 1 || FLT_EQ(sample, 1.0))
	) {
		do_sample = 0;
		sample = 1;
	}
	else
		do_sample = 1;
	RASTER_DEBUGF(3, "do_sample = %d", do_sample);

	/* sample all pixels */
	if (!do_sample) {
		sample_size = band->width * band->height;
		sample_per = band->height;
	}
	/*
	 randomly sample a percentage of available pixels
	 sampling method is known as
	 	"systematic random sample without replacement"
	*/
	else {
		sample_size = round((band->width * band->height) * sample);
		sample_per = round(sample_size / band->width);
		sample_int = round(band->height / sample_per);
		srand(time(NULL));
	}
	RASTER_DEBUGF(3, "sampling %d of %d available pixels w/ %d per set"
		, sample_size, (band->width * band->height), sample_per);

	for (x = 0, j = 0, k = 0; x < band->width; x++) {
		y = -1;
		diff = 0;

		for (i = 0, z = 0; i < sample_per; i++) {
			if (do_sample != 1)
				y = i;
			else {
				offset = (rand() % sample_int) + 1;
				y += diff + offset;
				diff = sample_int - offset;
			}
			RASTER_DEBUGF(5, "(x, y, z) = (%d, %d, %d)", x, y, z);
			if (y >= band->height || z > sample_per) break;

			status = rt_band_get_pixel(band, x, y, &value);

			j++;
			if (
				status != -1 && (
					!exclude_nodata_value || (
						exclude_nodata_value &&
						(hasnodata != FALSE) && (
							FLT_NEQ(value, nodata) &&
							(rt_band_clamped_value_is_nodata(band, value) != 1)
						)
					)
				)
			) {

				/* process each quantile */
				for (a = 0; a < *qlls_count; a++) {
					qll = &((*qlls)[a]);
					qls = NULL;
					RASTER_DEBUGF(4, "%d of %d (%f)", a + 1, *qlls_count, qll->quantile);
					RASTER_DEBUGF(5, "qll before: (algeq, quantile, count, tau, sum1, sum2) = (%d, %f, %d, %d, %d, %d)",
						qll->algeq, qll->quantile, qll->count, qll->tau, qll->sum1, qll->sum2);
					RASTER_DEBUGF(5, "qll before: (head, tail) = (%p, %p)", qll->head, qll->tail);

					/* OPTIMIZATION: shortcuts for quantiles of zero or one */
					if (FLT_EQ(qll->quantile, 0.)) {
						if (NULL != qll->head) {
							if (value < qll->head->value)
								qll->head->value = value;
						}
						else {
							qle = quantile_llist_insert(qll->head, value, NULL);
							qll->head = qle;
							qll->tail = qle;
							qll->count = 1;
						}

						RASTER_DEBUGF(4, "quantile shortcut for %f\n\n", qll->quantile);
						continue;
					}
					else if (FLT_EQ(qll->quantile, 1.)) {
						if (NULL != qll->head) {
							if (value > qll->head->value)
								qll->head->value = value;
						}
						else {
							qle = quantile_llist_insert(qll->head, value, NULL);
							qll->head = qle;
							qll->tail = qle;
							qll->count = 1;
						}

						RASTER_DEBUGF(4, "quantile shortcut for %f\n\n", qll->quantile);
						continue;
					}

					/* value exists in list */
					/* OPTIMIZATION: check to see if value exceeds last value */
					if (NULL != qll->tail && value > qll->tail->value)
						qle = NULL;
					/* OPTIMIZATION: check to see if value equals last value */
					else if (NULL != qll->tail && FLT_EQ(value, qll->tail->value))
						qle = qll->tail;
					/* OPTIMIZATION: use index if possible */
					else {
						qls = quantile_llist_index_search(qll, value, &idx);
						qle = quantile_llist_search(qls, value);
					}

					/* value found */
					if (NULL != qle) {
						RASTER_DEBUGF(4, "%f found in list", value);
						RASTER_DEBUGF(5, "qle before: (value, count) = (%f, %d)", qle->value, qle->count);

						qle->count++;
						qll->sum1++;

						if (qll->algeq)
							qll->sum2 = qll->sum1 - qll->head->count;
						else
							qll->sum2 = qll->sum1 - qll->tail->count;

						RASTER_DEBUGF(4, "qle after: (value, count) = (%f, %d)", qle->value, qle->count);
					}
					/* can still add element */
					else if (qll->count < MAX_VALUES) {
						RASTER_DEBUGF(4, "Adding %f to list", value);

						/* insert */
						/* OPTIMIZATION: check to see if value exceeds last value */
						if (NULL != qll->tail && (value > qll->tail->value || FLT_EQ(value, qll->tail->value))) {
							idx = qll->count;
							qle = quantile_llist_insert(qll->tail, value, &idx);
						}
						/* OPTIMIZATION: use index if possible */
						else
							qle = quantile_llist_insert(qls, value, &idx);
						if (NULL == qle) return NULL;
						RASTER_DEBUGF(5, "value added at index: %d => %f", idx, value);
						qll->count++;
						qll->sum1++;

						/* first element */
						if (NULL == qle->prev)
							qll->head = qle;
						/* last element */
						if (NULL == qle->next)
							qll->tail = qle;

						if (qll->algeq)
							qll->sum2 = qll->sum1 - qll->head->count;
						else
							qll->sum2 = qll->sum1 - qll->tail->count;

						/* index is only needed if there are at least 100 values */
						quantile_llist_index_update(qll, qle, idx);

						RASTER_DEBUGF(5, "qle, prev, next, head, tail = %p, %p, %p, %p, %p", qle, qle->prev, qle->next, qll->head, qll->tail);
					}
					/* AL-GEQ */
					else if (qll->algeq) {
						RASTER_DEBUGF(4, "value, head->value = %f, %f", value, qll->head->value);

						if (value < qll->head->value) {
							/* ignore value if test isn't true */
							if (qll->sum1 >= qll->tau) {
								RASTER_DEBUGF(4, "skipping %f", value);
							}
							else {

								/* delete last element */
								RASTER_DEBUGF(4, "deleting %f from list", qll->tail->value);
								qle = qll->tail->prev;
								RASTER_DEBUGF(5, "to-be tail is %f with count %d", qle->value, qle->count);
								qle->count += qll->tail->count;
								quantile_llist_index_delete(qll, qll->tail);
								quantile_llist_delete(qll->tail);
								qll->tail = qle;
								qll->count--;
								RASTER_DEBUGF(5, "tail is %f with count %d", qll->tail->value, qll->tail->count);

								/* insert value */
								RASTER_DEBUGF(4, "adding %f to list", value);
								/* OPTIMIZATION: check to see if value exceeds last value */
								if (NULL != qll->tail && (value > qll->tail->value || FLT_EQ(value, qll->tail->value))) {
									idx = qll->count;
									qle = quantile_llist_insert(qll->tail, value, &idx);
								}
								/* OPTIMIZATION: use index if possible */
								else {
									qls = quantile_llist_index_search(qll, value, &idx);
									qle = quantile_llist_insert(qls, value, &idx);
								}
								if (NULL == qle) return NULL;
								RASTER_DEBUGF(5, "value added at index: %d => %f", idx, value);
								qll->count++;
								qll->sum1++;

								/* first element */
								if (NULL == qle->prev)
									qll->head = qle;
								/* last element */
								if (NULL == qle->next)
									qll->tail = qle;

								qll->sum2 = qll->sum1 - qll->head->count;

								quantile_llist_index_update(qll, qle, idx);

								RASTER_DEBUGF(5, "qle, head, tail = %p, %p, %p", qle, qll->head, qll->tail);

							}
						}
						else {
							qle = qll->tail;
							while (NULL != qle) {
								if (qle->value < value) {
									qle->count++;
									qll->sum1++;
									qll->sum2 = qll->sum1 - qll->head->count;
									RASTER_DEBUGF(4, "incremented count of %f by 1 to %d", qle->value, qle->count);
									break;
								}

								qle = qle->prev;
							}
						}
					}
					/* AL-GT */
					else {
						RASTER_DEBUGF(4, "value, tail->value = %f, %f", value, qll->tail->value);

						if (value > qll->tail->value) {
							/* ignore value if test isn't true */
							if (qll->sum1 >= qll->tau) {
								RASTER_DEBUGF(4, "skipping %f", value);
							}
							else {

								/* delete last element */
								RASTER_DEBUGF(4, "deleting %f from list", qll->head->value);
								qle = qll->head->next;
								RASTER_DEBUGF(5, "to-be tail is %f with count %d", qle->value, qle->count);
								qle->count += qll->head->count;
								quantile_llist_index_delete(qll, qll->head);
								quantile_llist_delete(qll->head);
								qll->head = qle;
								qll->count--;
								quantile_llist_index_update(qll, NULL, 0);
								RASTER_DEBUGF(5, "tail is %f with count %d", qll->head->value, qll->head->count);

								/* insert value */
								RASTER_DEBUGF(4, "adding %f to list", value);
								/* OPTIMIZATION: check to see if value exceeds last value */
								if (NULL != qll->tail && (value > qll->tail->value || FLT_EQ(value, qll->tail->value))) {
									idx = qll->count;
									qle = quantile_llist_insert(qll->tail, value, &idx);
								}
								/* OPTIMIZATION: use index if possible */
								else {
									qls = quantile_llist_index_search(qll, value, &idx);
									qle = quantile_llist_insert(qls, value, &idx);
								}
								if (NULL == qle) return NULL;
								RASTER_DEBUGF(5, "value added at index: %d => %f", idx, value);
								qll->count++;
								qll->sum1++;

								/* first element */
								if (NULL == qle->prev)
									qll->head = qle;
								/* last element */
								if (NULL == qle->next)
									qll->tail = qle;

								qll->sum2 = qll->sum1 - qll->tail->count;

								quantile_llist_index_update(qll, qle, idx);

								RASTER_DEBUGF(5, "qle, head, tail = %p, %p, %p", qle, qll->head, qll->tail);

							}
						}
						else {
							qle = qll->head;
							while (NULL != qle) {
								if (qle->value > value) {
									qle->count++;
									qll->sum1++;
									qll->sum2 = qll->sum1 - qll->tail->count;
									RASTER_DEBUGF(4, "incremented count of %f by 1 to %d", qle->value, qle->count);
									break;
								}

								qle = qle->next;
							}
						}
					}

					RASTER_DEBUGF(5, "sum2, tau = %d, %d", qll->sum2, qll->tau);
					if (qll->sum2 >= qll->tau) {
						/* AL-GEQ */
						if (qll->algeq) {
							RASTER_DEBUGF(4, "deleting first element %f from list", qll->head->value);

							if (NULL != qll->head->next) {
								qle = qll->head->next;
								qll->sum1 -= qll->head->count;
								qll->sum2 = qll->sum1 - qle->count;
								quantile_llist_index_delete(qll, qll->head);
								quantile_llist_delete(qll->head);
								qll->head = qle;
								qll->count--;

								quantile_llist_index_update(qll, NULL, 0);
							}
							else {
								quantile_llist_delete(qll->head);
								qll->head = NULL;
								qll->tail = NULL;
								qll->sum1 = 0;
								qll->sum2 = 0;
								qll->count = 0;

								quantile_llist_index_reset(qll);
							}
						}
						/* AL-GT */
						else {
							RASTER_DEBUGF(4, "deleting first element %f from list", qll->tail->value);

							if (NULL != qll->tail->prev) {
								qle = qll->tail->prev;
								qll->sum1 -= qll->tail->count;
								qll->sum2 = qll->sum1 - qle->count;
								quantile_llist_index_delete(qll, qll->tail);
								quantile_llist_delete(qll->tail);
								qll->tail = qle;
								qll->count--;
							}
							else {
								quantile_llist_delete(qll->tail);
								qll->head = NULL;
								qll->tail = NULL;
								qll->sum1 = 0;
								qll->sum2 = 0;
								qll->count = 0;

								quantile_llist_index_reset(qll);
							}
						}
					}

					RASTER_DEBUGF(5, "qll after: (algeq, quantile, count, tau, sum1, sum2) = (%d, %f, %d, %d, %d, %d)",
						qll->algeq, qll->quantile, qll->count, qll->tau, qll->sum1, qll->sum2);
					RASTER_DEBUGF(5, "qll after: (head, tail) = (%p, %p)\n\n", qll->head, qll->tail);
				}

			}
			else {
				RASTER_DEBUGF(5, "skipping value at (x, y) = (%d, %d)", x, y);
			}

			z++;
		}
	}

	/* process quantiles */
	*rtn_count = *qlls_count / 2;
	rtn = rtalloc(sizeof(struct rt_quantile_t) * *rtn_count);
	if (NULL == rtn) return NULL;

	RASTER_DEBUGF(3, "returning %d quantiles", *rtn_count);
	for (i = 0, k = 0; i < *qlls_count; i++) {
		qll = &((*qlls)[i]);

		exists = 0;
		for (x = 0; x < k; x++) {
			if (FLT_EQ(qll->quantile, rtn[x].quantile)) {
				exists = 1;
				break;
			}
		}
		if (exists) continue;

		RASTER_DEBUGF(5, "qll: (algeq, quantile, count, tau, sum1, sum2) = (%d, %f, %d, %d, %d, %d)",
			qll->algeq, qll->quantile, qll->count, qll->tau, qll->sum1, qll->sum2);
		RASTER_DEBUGF(5, "qll: (head, tail) = (%p, %p)", qll->head, qll->tail);

		rtn[k].quantile = qll->quantile;
		rtn[k].has_value = 0;

		/* check that qll->head and qll->tail have value */
		if (qll->head == NULL || qll->tail == NULL)
			continue;

		/* AL-GEQ */
		if (qll->algeq)
			qle = qll->head;
		/* AM-GT */
		else
			qle = qll->tail;

		exists = 0;
		for (j = i + 1; j < *qlls_count; j++) {
			if (FLT_EQ((*qlls)[j].quantile, qll->quantile)) {

				RASTER_DEBUGF(5, "qlls[%d]: (algeq, quantile, count, tau, sum1, sum2) = (%d, %f, %d, %d, %d, %d)",
					j, (*qlls)[j].algeq, (*qlls)[j].quantile, (*qlls)[j].count, (*qlls)[j].tau, (*qlls)[j].sum1, (*qlls)[j].sum2);
				RASTER_DEBUGF(5, "qlls[%d]: (head, tail) = (%p, %p)", j, (*qlls)[j].head, (*qlls)[j].tail);

				exists = 1;
				break;
			}
		}

		/* weighted average for quantile */
		if (exists) {
			if ((*qlls)[j].algeq) {
				rtn[k].value = ((qle->value * qle->count) + ((*qlls)[j].head->value * (*qlls)[j].head->count)) / (qle->count + (*qlls)[j].head->count);
				RASTER_DEBUGF(5, "qlls[%d].head: (value, count) = (%f, %d)", j, (*qlls)[j].head->value, (*qlls)[j].head->count);
			}
			else {
				rtn[k].value = ((qle->value * qle->count) + ((*qlls)[j].tail->value * (*qlls)[j].tail->count)) / (qle->count + (*qlls)[j].tail->count);
				RASTER_DEBUGF(5, "qlls[%d].tail: (value, count) = (%f, %d)", j, (*qlls)[j].tail->value, (*qlls)[j].tail->count);
			}
		}
		/* straight value for quantile */
		else {
			rtn[k].value = qle->value;
		}
		rtn[k].has_value = 1;
		RASTER_DEBUGF(3, "(quantile, value) = (%f, %f)\n\n", rtn[k].quantile, rtn[k].value);

		k++;
	}

	RASTER_DEBUG(3, "done");
	return rtn;
}

/**
 * Count the number of times provided value(s) occur in
 * the band
 *
 * @param band: the band to query for minimum and maximum pixel values
 * @param exclude_nodata_value: if non-zero, ignore nodata values
 * @param search_values: array of values to count
 * @param search_values_count: the number of search values
 * @param roundto: the decimal place to round the values to
 * @param rtn_total: the number of pixels examined in the band
 * @param rtn_count: the number of value counts being returned
 *
 * @return the number of times the provide value(s) occur
 */
rt_valuecount
rt_band_get_value_count(rt_band band, int exclude_nodata_value,
	double *search_values, uint32_t search_values_count, double roundto,
	uint32_t *rtn_total, uint32_t *rtn_count) {
	rt_valuecount vcnts = NULL;
	rt_pixtype pixtype = PT_END;
	uint8_t *data = NULL;
	int hasnodata = FALSE;
	double nodata = 0;

	int scale = 0;
	int doround = 0;
	double tmpd = 0;
	int i = 0;

	uint32_t x = 0;
	uint32_t y = 0;
	int rtn;
	double pxlval;
	double rpxlval;
	uint32_t total = 0;
	int vcnts_count = 0;
	int new_valuecount = 0;

#if POSTGIS_DEBUG_LEVEL > 0
	clock_t start, stop;
	double elapsed = 0;
#endif

	RASTER_DEBUG(3, "starting");
#if POSTGIS_DEBUG_LEVEL > 0
	start = clock();
#endif

	assert(NULL != band);

	data = rt_band_get_data(band);
	if (data == NULL) {
		rterror("rt_band_get_summary_stats: Cannot get band data");
		return NULL;
	}

	pixtype = band->pixtype;

	hasnodata = rt_band_get_hasnodata_flag(band);
	if (hasnodata != FALSE)
		nodata = rt_band_get_nodata(band);
	else
		exclude_nodata_value = 0;

	RASTER_DEBUGF(3, "nodata = %f", nodata);
	RASTER_DEBUGF(3, "hasnodata = %d", hasnodata);
	RASTER_DEBUGF(3, "exclude_nodata_value = %d", exclude_nodata_value);

	/* process roundto */
	if (roundto < 0 || FLT_EQ(roundto, 0.0)) {
		roundto = 0;
		scale = 0;
	}
	/* tenths, hundredths, thousandths, etc */
	else if (roundto < 1) {
    switch (pixtype) {
			/* integer band types don't have digits after the decimal place */
			case PT_1BB:
			case PT_2BUI:
			case PT_4BUI:
			case PT_8BSI:
			case PT_8BUI:
			case PT_16BSI:
			case PT_16BUI:
			case PT_32BSI:
			case PT_32BUI:
				roundto = 0;
				break;
			/* floating points, check the rounding */
			case PT_32BF:
			case PT_64BF:
				for (scale = 0; scale <= 20; scale++) {
					tmpd = roundto * pow(10, scale);
					if (FLT_EQ((tmpd - ((int) tmpd)), 0.0)) break;
				}
				break;
			case PT_END:
				break;
		}
	}
	/* ones, tens, hundreds, etc */
	else {
		for (scale = 0; scale >= -20; scale--) {
			tmpd = roundto * pow(10, scale);
			if (tmpd < 1 || FLT_EQ(tmpd, 1.0)) {
				if (scale == 0) doround = 1;
				break;
			}
		}
	}

	if (scale != 0 || doround)
		doround = 1;
	else
		doround = 0;
	RASTER_DEBUGF(3, "scale = %d", scale);
	RASTER_DEBUGF(3, "doround = %d", doround);

	/* process search_values */
	if (search_values_count > 0 && NULL != search_values) {
		vcnts = (rt_valuecount) rtalloc(sizeof(struct rt_valuecount_t) * search_values_count);
		if (NULL == vcnts) {
			rterror("rt_band_get_count_of_values: Unable to allocate memory for value counts");
			*rtn_count = 0;
			return NULL;
		}

		for (i = 0; i < search_values_count; i++) {
			vcnts[i].count = 0;
			vcnts[i].percent = 0;
			if (!doround)
				vcnts[i].value = search_values[i];
			else
				vcnts[i].value = ROUND(search_values[i], scale);
		}
		vcnts_count = i;
	}
	else
		search_values_count = 0;
	RASTER_DEBUGF(3, "search_values_count = %d", search_values_count);

	/* entire band is nodata */
	if (rt_band_get_isnodata_flag(band) != FALSE) {
		if (exclude_nodata_value) {
			rtwarn("All pixels of band have the NODATA value");
			return NULL;
		}
		else {
			if (search_values_count > 0) {
				/* check for nodata match */
				for (i = 0; i < search_values_count; i++) {
					if (!doround)
						tmpd = nodata;
					else
						tmpd = ROUND(nodata, scale);

					if (FLT_NEQ(tmpd, vcnts[i].value))
						continue;

					vcnts[i].count = band->width * band->height;
					if (NULL != rtn_total) *rtn_total = vcnts[i].count;
					vcnts->percent = 1.0;
				}

				*rtn_count = vcnts_count;
			}
			/* no defined search values */
			else {
				vcnts = (rt_valuecount) rtalloc(sizeof(struct rt_valuecount_t));
				if (NULL == vcnts) {
					rterror("rt_band_get_count_of_values: Unable to allocate memory for value counts");
					*rtn_count = 0;
					return NULL;
				}

				vcnts->value = nodata;
				vcnts->count = band->width * band->height;
				if (NULL != rtn_total) *rtn_total = vcnts[i].count;
				vcnts->percent = 1.0;

				*rtn_count = 1;
			}

			return vcnts;
		}
	}

	for (x = 0; x < band->width; x++) {
		for (y = 0; y < band->height; y++) {
			rtn = rt_band_get_pixel(band, x, y, &pxlval);

			/* error getting value, continue */
			if (rtn == -1) continue;

			if (
				!exclude_nodata_value || (
					exclude_nodata_value &&
					(hasnodata != FALSE) && (
						FLT_NEQ(pxlval, nodata) &&
						(rt_band_clamped_value_is_nodata(band, pxlval) != 1)
					)
				)
			) {
				total++;
				if (doround) {
					rpxlval = ROUND(pxlval, scale);
				}
				else
					rpxlval = pxlval;
				RASTER_DEBUGF(5, "(pxlval, rpxlval) => (%0.6f, %0.6f)", pxlval, rpxlval);

				new_valuecount = 1;
				/* search for match in existing valuecounts */
				for (i = 0; i < vcnts_count; i++) {
					/* match found */
					if (FLT_EQ(vcnts[i].value, rpxlval)) {
						vcnts[i].count++;
						new_valuecount = 0;
						RASTER_DEBUGF(5, "(value, count) => (%0.6f, %d)", vcnts[i].value, vcnts[i].count);
						break;
					}
				}

				/*
					don't add new valuecount either because
						- no need for new one
						- user-defined search values
				*/
				if (!new_valuecount || search_values_count > 0) continue;

				/* add new valuecount */
				vcnts = rtrealloc(vcnts, sizeof(struct rt_valuecount_t) * (vcnts_count + 1));
				if (NULL == vcnts) {
					rterror("rt_band_get_count_of_values: Unable to allocate memory for value counts");
					*rtn_count = 0;
					return NULL;
				}

				vcnts[vcnts_count].value = rpxlval;
				vcnts[vcnts_count].count = 1;
				vcnts[vcnts_count].percent = 0;
				RASTER_DEBUGF(5, "(value, count) => (%0.6f, %d)", vcnts[vcnts_count].value, vcnts[vcnts_count].count);
				vcnts_count++;
			}
		}
	}

#if POSTGIS_DEBUG_LEVEL > 0
	stop = clock();
	elapsed = ((double) (stop - start)) / CLOCKS_PER_SEC;
	RASTER_DEBUGF(3, "elapsed time = %0.4f", elapsed);
#endif

	for (i = 0; i < vcnts_count; i++) {
		vcnts[i].percent = (double) vcnts[i].count / total;
		RASTER_DEBUGF(5, "(value, count) => (%0.6f, %d)", vcnts[i].value, vcnts[i].count);
	}

	RASTER_DEBUG(3, "done");
	if (NULL != rtn_total) *rtn_total = total;
	*rtn_count = vcnts_count;
	return vcnts;
}

/**
 * Returns new band with values reclassified
 *
 * @param srcband : the band who's values will be reclassified
 * @param pixtype : pixel type of the new band
 * @param hasnodata : indicates if the band has a nodata value
 * @param nodataval : nodata value for the new band
 * @param exprset : array of rt_reclassexpr structs
 * @param exprcount : number of elements in expr
 *
 * @return a new rt_band or 0 on error
 */
rt_band
rt_band_reclass(rt_band srcband, rt_pixtype pixtype,
	uint32_t hasnodata, double nodataval, rt_reclassexpr *exprset,
	int exprcount) {
	rt_band band = NULL;
	uint32_t width = 0;
	uint32_t height = 0;
	int numval = 0;
	int memsize = 0;
	void *mem = NULL;
	uint32_t src_hasnodata = 0;
	double src_nodataval = 0.0;

	int rtn;
	uint32_t x;
	uint32_t y;
	int i;
	double or = 0;
	double ov = 0;
	double nr = 0;
	double nv = 0;
	int do_nv = 0;
	rt_reclassexpr expr = NULL;

	assert(NULL != srcband);
	assert(NULL != exprset);

	/* source nodata */
	src_hasnodata = rt_band_get_hasnodata_flag(srcband);
	src_nodataval = rt_band_get_nodata(srcband);

	/* size of memory block to allocate */
	width = rt_band_get_width(srcband);
	height = rt_band_get_height(srcband);
	numval = width * height;
	memsize = rt_pixtype_size(pixtype) * numval;
	mem = (int *) rtalloc(memsize);
	if (!mem) {
		rterror("rt_band_reclass: Could not allocate memory for band");
		return 0;
	}

	/* initialize to zero */
	if (!hasnodata) {
		memset(mem, 0, memsize);
	}
	/* initialize to nodataval */
	else {
		int32_t checkvalint = 0;
		uint32_t checkvaluint = 0;
		double checkvaldouble = 0;
		float checkvalfloat = 0;

		switch (pixtype) {
			case PT_1BB:
			{
				uint8_t *ptr = mem;
				uint8_t clamped_initval = rt_util_clamp_to_1BB(nodataval);
				for (i = 0; i < numval; i++)
					ptr[i] = clamped_initval;
				checkvalint = ptr[0];
				break;
			}
			case PT_2BUI:
			{
				uint8_t *ptr = mem;
				uint8_t clamped_initval = rt_util_clamp_to_2BUI(nodataval);
				for (i = 0; i < numval; i++)
					ptr[i] = clamped_initval;
				checkvalint = ptr[0];
				break;
			}
			case PT_4BUI:
			{
				uint8_t *ptr = mem;
				uint8_t clamped_initval = rt_util_clamp_to_4BUI(nodataval);
				for (i = 0; i < numval; i++)
					ptr[i] = clamped_initval;
				checkvalint = ptr[0];
				break;
			}
			case PT_8BSI:
			{
				int8_t *ptr = mem;
				int8_t clamped_initval = rt_util_clamp_to_8BSI(nodataval);
				for (i = 0; i < numval; i++)
					ptr[i] = clamped_initval;
				checkvalint = ptr[0];
				break;
			}
			case PT_8BUI:
			{
				uint8_t *ptr = mem;
				uint8_t clamped_initval = rt_util_clamp_to_8BUI(nodataval);
				for (i = 0; i < numval; i++)
					ptr[i] = clamped_initval;
				checkvalint = ptr[0];
				break;
			}
			case PT_16BSI:
			{
				int16_t *ptr = mem;
				int16_t clamped_initval = rt_util_clamp_to_16BSI(nodataval);
				for (i = 0; i < numval; i++)
					ptr[i] = clamped_initval;
				checkvalint = ptr[0];
				break;
			}
			case PT_16BUI:
			{
				uint16_t *ptr = mem;
				uint16_t clamped_initval = rt_util_clamp_to_16BUI(nodataval);
				for (i = 0; i < numval; i++)
					ptr[i] = clamped_initval;
				checkvalint = ptr[0];
				break;
			}
			case PT_32BSI:
			{
				int32_t *ptr = mem;
				int32_t clamped_initval = rt_util_clamp_to_32BSI(nodataval);
				for (i = 0; i < numval; i++)
					ptr[i] = clamped_initval;
				checkvalint = ptr[0];
				break;
			}
			case PT_32BUI:
			{
				uint32_t *ptr = mem;
				uint32_t clamped_initval = rt_util_clamp_to_32BUI(nodataval);
				for (i = 0; i < numval; i++)
					ptr[i] = clamped_initval;
				checkvaluint = ptr[0];
				break;
			}
			case PT_32BF:
			{
				float *ptr = mem;
				float clamped_initval = rt_util_clamp_to_32F(nodataval);
				for (i = 0; i < numval; i++)
					ptr[i] = clamped_initval;
				checkvalfloat = ptr[0];
				break;
			}
			case PT_64BF:
			{
				double *ptr = mem;
				for (i = 0; i < numval; i++)
					ptr[i] = nodataval;
				checkvaldouble = ptr[0];
				break;
			}
			default:
			{
				rterror("rt_band_reclass: Unknown pixeltype %d", pixtype);
				rtdealloc(mem);
				return 0;
			}
		}

		/* Overflow checking */
		rt_util_dbl_trunc_warning(
			nodataval,
			checkvalint, checkvaluint,
			checkvalfloat, checkvaldouble,
			pixtype
		);
	}
	RASTER_DEBUGF(3, "rt_band_reclass: width = %d height = %d", width, height);

	band = rt_band_new_inline(width, height, pixtype, hasnodata, nodataval, mem);
	if (!band) {
		rterror("rt_band_reclass: Could not create new band");
		rtdealloc(mem);
		return 0;
	}
	RASTER_DEBUGF(3, "rt_band_reclass: new band @ %p", band);

	for (x = 0; x < width; x++) {
		for (y = 0; y < height; y++) {
			rtn = rt_band_get_pixel(srcband, x, y, &ov);

			/* error getting value, skip */
			if (rtn == -1) {
				RASTER_DEBUGF(3, "Cannot get value at %d, %d", x, y);
				continue;
			}

			do {
				do_nv = 0;

				/* no data*/
				if (src_hasnodata && hasnodata && FLT_EQ(ov, src_nodataval)) {
					do_nv = 1;
					break;
				}

				for (i = 0; i < exprcount; i++) {
					expr = exprset[i];

					/* ov matches min and max*/
					if (
						FLT_EQ(expr->src.min, ov) &&
						FLT_EQ(expr->src.max, ov)
					) {
						do_nv = 1;
						break;
					}

					/* process min */
					if ((
						expr->src.exc_min && (
							expr->src.min > ov ||
							FLT_EQ(expr->src.min, ov)
						)) || (
						expr->src.inc_min && (
							expr->src.min < ov ||
							FLT_EQ(expr->src.min, ov)
						)) || (
						expr->src.min < ov
					)) {
						/* process max */
						if ((
							expr->src.exc_max && (
								ov > expr->src.max ||
								FLT_EQ(expr->src.max, ov)
							)) || (
								expr->src.inc_max && (
								ov < expr->src.max ||
								FLT_EQ(expr->src.max, ov)
							)) || (
							ov < expr->src.max
						)) {
							do_nv = 1;
							break;
						}
					}
				}
			}
			while (0);

			/* no expression matched, do not continue */
			if (!do_nv) continue;

			/* converting a value from one range to another range
			OldRange = (OldMax - OldMin)
			NewRange = (NewMax - NewMin)
			NewValue = (((OldValue - OldMin) * NewRange) / OldRange) + NewMin
			*/

			/* nodata */
			if (
				src_hasnodata &&
				hasnodata &&
				FLT_EQ(ov, src_nodataval)
			) {
				nv = nodataval;
			}
			/*
				"src" min and max is the same, prevent division by zero
				set nv to "dst" min, which should be the same as "dst" max
			*/
			else if (FLT_EQ(expr->src.max, expr->src.min)) {
				nv = expr->dst.min;
			}
			else {
				or = expr->src.max - expr->src.min;
				nr = expr->dst.max - expr->dst.min;
				nv = (((ov - expr->src.min) * nr) / or) + expr->dst.min;

				/* if dst range is from high to low */
				if (expr->dst.min > expr->dst.max) {
					if (nv > expr->dst.min)
						nv = expr->dst.min;
					else if (nv < expr->dst.max)
						nv = expr->dst.max;
				}
				/* if dst range is from low to high */
				else {
					if (nv < expr->dst.min)
						nv = expr->dst.min;
					else if (nv > expr->dst.max)
						nv = expr->dst.max;
				}
			}

			/* round the value for integers */
			switch (pixtype) {
				case PT_1BB:
				case PT_2BUI:
				case PT_4BUI:
				case PT_8BSI:
				case PT_8BUI:
				case PT_16BSI:
				case PT_16BUI:
				case PT_32BSI:
				case PT_32BUI:
					nv = round(nv);
					break;
				default:
					break;
			}

			RASTER_DEBUGF(3, "(%d, %d) ov: %f or: %f - %f nr: %f - %f nv: %f"
				, x
				, y
				, ov
				, (NULL != expr) ? expr->src.min : 0
				, (NULL != expr) ? expr->src.max : 0
				, (NULL != expr) ? expr->dst.min : 0
				, (NULL != expr) ? expr->dst.max : 0
				, nv
			);
			if (rt_band_set_pixel(band, x, y, nv) < 0) {
				rterror("rt_band_reclass: Could not assign value to new band");
				rt_band_destroy(band);
				rtdealloc(mem);
				return 0;
			}

			expr = NULL;
		}
	}

	return band;
}

/*- rt_raster --------------------------------------------------------*/

rt_raster
rt_raster_new(uint32_t width, uint32_t height) {
	rt_raster ret = NULL;

	ret = (rt_raster) rtalloc(sizeof (struct rt_raster_t));
	if (!ret) {
		rterror("rt_raster_new: Out of virtual memory creating an rt_raster");
		return NULL;
	}

	RASTER_DEBUGF(3, "Created rt_raster @ %p", ret);

	assert(NULL != ret);

	if (width > 65535 || height > 65535) {
		rterror("rt_raster_new: Dimensions requested exceed the maximum (65535 x 65535) permitted for a raster");
		return NULL;
	}

	ret->width = width;
	ret->height = height;
	ret->scaleX = 1;
	ret->scaleY = 1;
	ret->ipX = 0.0;
	ret->ipY = 0.0;
	ret->skewX = 0.0;
	ret->skewY = 0.0;
	ret->srid = SRID_UNKNOWN;

	ret->numBands = 0;
	ret->bands = 0; 
	return ret;
}

void
rt_raster_destroy(rt_raster raster) {


    RASTER_DEBUGF(3, "Destroying rt_raster @ %p", raster);

    if (raster->bands) {
        rtdealloc(raster->bands);
    }
    rtdealloc(raster);
}

uint16_t
rt_raster_get_width(rt_raster raster) {

    assert(NULL != raster);

    return raster->width;
}

uint16_t
rt_raster_get_height(rt_raster raster) {

    assert(NULL != raster);

    return raster->height;
}

void
rt_raster_set_scale(rt_raster raster,
        double scaleX, double scaleY) {


    assert(NULL != raster);

    raster->scaleX = scaleX;
    raster->scaleY = scaleY;
}

double
rt_raster_get_x_scale(rt_raster raster) {


    assert(NULL != raster);

    return raster->scaleX;
}

double
rt_raster_get_y_scale(rt_raster raster) {


    assert(NULL != raster);

    return raster->scaleY;
}

void
rt_raster_set_skews(rt_raster raster,
        double skewX, double skewY) {


    assert(NULL != raster);

    raster->skewX = skewX;
    raster->skewY = skewY;
}

double
rt_raster_get_x_skew(rt_raster raster) {


    assert(NULL != raster);

    return raster->skewX;
}

double
rt_raster_get_y_skew(rt_raster raster) {


    assert(NULL != raster);

    return raster->skewY;
}

void
rt_raster_set_offsets(rt_raster raster, double x, double y) {


    assert(NULL != raster);

    raster->ipX = x;
    raster->ipY = y;
}

double
rt_raster_get_x_offset(rt_raster raster) {


    assert(NULL != raster);

    return raster->ipX;
}

double
rt_raster_get_y_offset(rt_raster raster) {


    assert(NULL != raster);

    return raster->ipY;
}

void
rt_raster_get_phys_params(rt_raster rast,
        double *i_mag, double *j_mag, double *theta_i, double *theta_ij)
{
    double o11, o12, o21, o22 ; /* geotransform coefficients */

    if (rast == NULL) return ;
    if ( (i_mag==NULL) || (j_mag==NULL) || (theta_i==NULL) || (theta_ij==NULL))
        return ;

    /* retrieve coefficients from raster */
    o11 = rt_raster_get_x_scale(rast) ;
    o12 = rt_raster_get_x_skew(rast) ;
    o21 = rt_raster_get_y_skew(rast) ;
    o22 = rt_raster_get_y_scale(rast) ;

    rt_raster_calc_phys_params(o11, o12, o21, o22, i_mag, j_mag, theta_i, theta_ij);
}

void
rt_raster_calc_phys_params(double xscale, double xskew, double yskew, double yscale,
                           double *i_mag, double *j_mag, double *theta_i, double *theta_ij)

{
    double theta_test ;

    if ( (i_mag==NULL) || (j_mag==NULL) || (theta_i==NULL) || (theta_ij==NULL))
        return ;

    /* pixel size in the i direction */
    *i_mag = sqrt(xscale*xscale + yskew*yskew) ;

    /* pixel size in the j direction */
    *j_mag = sqrt(xskew*xskew + yscale*yscale) ;

    /* Rotation
     * ========
     * Two steps:
     * 1] calculate the magnitude of the angle between the x axis and
     *     the i basis vector.
     * 2] Calculate the sign of theta_i based on the angle between the y axis
     *     and the i basis vector.
     */
    *theta_i = acos(xscale/(*i_mag)) ;  /* magnitude */
    theta_test = acos(yskew/(*i_mag)) ; /* sign */
    if (theta_test < M_PI_2){
        *theta_i = -(*theta_i) ;
    }


    /* Angular separation of basis vectors
     * ===================================
     * Two steps:
     * 1] calculate the magnitude of the angle between the j basis vector and
     *     the i basis vector.
     * 2] Calculate the sign of theta_ij based on the angle between the
     *    perpendicular of the i basis vector and the j basis vector.
     */
    *theta_ij = acos(((xscale*xskew) + (yskew*yscale))/((*i_mag)*(*j_mag))) ;
    theta_test = acos( ((-yskew*xskew)+(xscale*yscale)) /
            ((*i_mag)*(*j_mag)));
    if (theta_test > M_PI_2) {
        *theta_ij = -(*theta_ij) ;
    }
}

void
rt_raster_set_phys_params(rt_raster rast,double i_mag, double j_mag, double theta_i, double theta_ij)
{
    double o11, o12, o21, o22 ; /* calculated geotransform coefficients */
    int success ;

    if (rast == NULL) return ;

    success = rt_raster_calc_gt_coeff(i_mag, j_mag, theta_i, theta_ij,
                            &o11, &o12, &o21, &o22) ;

    if (success) {
        rt_raster_set_scale(rast, o11, o22) ;
        rt_raster_set_skews(rast, o12, o21) ;
    }
}

int
rt_raster_calc_gt_coeff(double i_mag, double j_mag, double theta_i, double theta_ij,
                        double *xscale, double *xskew, double *yskew, double *yscale)
{
    double f ;        /* reflection flag 1.0 or -1.0 */
    double k_i ;      /* shearing coefficient */
    double s_i, s_j ; /* scaling coefficients */
    double cos_theta_i, sin_theta_i ;

    if ( (xscale==NULL) || (xskew==NULL) || (yskew==NULL) || (yscale==NULL)) {
        return 0;
    }

    if ( (theta_ij == 0.0) || (theta_ij == M_PI)) {
        return 0;
    }

    /* Reflection across the i axis */
    f=1.0 ;
    if (theta_ij < 0) {
        f = -1.0;
    }

    /* scaling along i axis */
    s_i = i_mag ;

    /* shearing parallel to i axis */
    k_i = tan(f*M_PI_2 - theta_ij) ;

    /* scaling along j axis */
    s_j = j_mag / (sqrt(k_i*k_i + 1)) ;

    /* putting it altogether */
    cos_theta_i = cos(theta_i) ;
    sin_theta_i = sin(theta_i) ;
    *xscale = s_i * cos_theta_i ;
    *xskew  = k_i * s_j * f * cos_theta_i + s_j * f * sin_theta_i ;
    *yskew  = -s_i * sin_theta_i ;
    *yscale = -k_i * s_j * f * sin_theta_i + s_j * f * cos_theta_i ;
    return 1;
}

int32_t
rt_raster_get_srid(rt_raster raster) {
	assert(NULL != raster);

	return clamp_srid(raster->srid);
}

void
rt_raster_set_srid(rt_raster raster, int32_t srid) {
	assert(NULL != raster);

	raster->srid = clamp_srid(srid);
}

int
rt_raster_get_num_bands(rt_raster raster) {


    assert(NULL != raster);

    return raster->numBands;
}

rt_band
rt_raster_get_band(rt_raster raster, int n) {


    assert(NULL != raster);

    if (n >= raster->numBands || n < 0) return 0;
    return raster->bands[n];
}

/**
 * Add band data to a raster.
 *
 * @param raster : the raster to add a band to
 * @param band : the band to add, ownership left to caller.
 *               Band dimensions are required to match with raster ones.
 * @param index : the position where to insert the new band (0 based)
 *
 * @return identifier (position) for the just-added raster, or -1 on error
 */
int32_t
rt_raster_add_band(rt_raster raster, rt_band band, int index) {
    rt_band *oldbands = NULL;
    rt_band oldband = NULL;
    rt_band tmpband = NULL;
    uint16_t i = 0;



    assert(NULL != raster);

    RASTER_DEBUGF(3, "Adding band %p to raster %p", band, raster);

    if (band->width != raster->width || band->height != raster->height) {
        rterror("rt_raster_add_band: Can't add a %dx%d band to a %dx%d raster",
                band->width, band->height, raster->width, raster->height);
        return -1;
    }

    if (index > raster->numBands)
        index = raster->numBands;

    if (index < 0)
        index = 0;

    oldbands = raster->bands;

    RASTER_DEBUGF(3, "Oldbands at %p", oldbands);

    raster->bands = (rt_band*) rtrealloc(raster->bands,
            sizeof (rt_band)*(raster->numBands + 1)
            );

    RASTER_DEBUG(3, "Checking bands");

    if (NULL == raster->bands) {
        rterror("rt_raster_add_band: Out of virtual memory "
                "reallocating band pointers");
        raster->bands = oldbands;
        return -1;
    }

    RASTER_DEBUGF(4, "realloc returned %p", raster->bands);

    for (i = 0; i <= raster->numBands; ++i) {
        if (i == index) {
            oldband = raster->bands[i];
            raster->bands[i] = band;
        } else if (i > index) {
            tmpband = raster->bands[i];
            raster->bands[i] = oldband;
            oldband = tmpband;
        }
    }

		band->raster = raster;

    raster->numBands++;

    RASTER_DEBUGF(4, "now raster has %d bands", raster->numBands);

    return index;
}

/**
 * Generate a new inline band and add it to a raster.
 *
 * @param raster : the raster to add a band to
 * @param pixtype: the pixel type for the new band
 * @param initialvalue: initial value for pixels
 * @param hasnodata: indicates if the band has a nodata value
 * @param nodatavalue: nodata value for the new band
 * @param index: position to add the new band in the raster
 *
 * @return identifier (position) for the just-added raster, or -1 on error
 */
int32_t
rt_raster_generate_new_band(rt_raster raster, rt_pixtype pixtype,
        double initialvalue, uint32_t hasnodata, double nodatavalue, int index)
{
    rt_band band = NULL;
    int width = 0;
    int height = 0;
    int numval = 0;
    int datasize = 0;
    int oldnumbands = 0;
    int numbands = 0;
    void * mem = NULL;
    int32_t checkvalint = 0;
    uint32_t checkvaluint = 0;
    double checkvaldouble = 0;
    float checkvalfloat = 0;
    int i;


    assert(NULL != raster);

    /* Make sure index is in a valid range */
    oldnumbands = rt_raster_get_num_bands(raster);
    if (index < 0)
        index = 0;
    else if (index > oldnumbands + 1)
        index = oldnumbands + 1;

    /* Determine size of memory block to allocate and allocate it */
    width = rt_raster_get_width(raster);
    height = rt_raster_get_height(raster);
    numval = width * height;
    datasize = rt_pixtype_size(pixtype) * numval;

    mem = (int *)rtalloc(datasize);
    if (!mem) {
        rterror("rt_raster_generate_new_band: Could not allocate memory for band");
        return -1;
    }

    if (FLT_EQ(initialvalue, 0.0))
        memset(mem, 0, datasize);
    else {
        switch (pixtype)
        {
            case PT_1BB:
            {
                uint8_t *ptr = mem;
                uint8_t clamped_initval = rt_util_clamp_to_1BB(initialvalue);
                for (i = 0; i < numval; i++)
                    ptr[i] = clamped_initval;
                checkvalint = ptr[0];
                break;
            }
            case PT_2BUI:
            {
                uint8_t *ptr = mem;
                uint8_t clamped_initval = rt_util_clamp_to_2BUI(initialvalue);
                for (i = 0; i < numval; i++)
                    ptr[i] = clamped_initval;
                checkvalint = ptr[0];
                break;
            }
            case PT_4BUI:
            {
                uint8_t *ptr = mem;
                uint8_t clamped_initval = rt_util_clamp_to_4BUI(initialvalue);
                for (i = 0; i < numval; i++)
                    ptr[i] = clamped_initval;
                checkvalint = ptr[0];
                break;
            }
            case PT_8BSI:
            {
                int8_t *ptr = mem;
                int8_t clamped_initval = rt_util_clamp_to_8BSI(initialvalue);
                for (i = 0; i < numval; i++)
                    ptr[i] = clamped_initval;
                checkvalint = ptr[0];
                break;
            }
            case PT_8BUI:
            {
                uint8_t *ptr = mem;
                uint8_t clamped_initval = rt_util_clamp_to_8BUI(initialvalue);
                for (i = 0; i < numval; i++)
                    ptr[i] = clamped_initval;
                checkvalint = ptr[0];
                break;
            }
            case PT_16BSI:
            {
                int16_t *ptr = mem;
                int16_t clamped_initval = rt_util_clamp_to_16BSI(initialvalue);
                for (i = 0; i < numval; i++)
                    ptr[i] = clamped_initval;
                checkvalint = ptr[0];
                break;
            }
            case PT_16BUI:
            {
                uint16_t *ptr = mem;
                uint16_t clamped_initval = rt_util_clamp_to_16BUI(initialvalue);
                for (i = 0; i < numval; i++)
                    ptr[i] = clamped_initval;
                checkvalint = ptr[0];
                break;
            }
            case PT_32BSI:
            {
                int32_t *ptr = mem;
                int32_t clamped_initval = rt_util_clamp_to_32BSI(initialvalue);
                for (i = 0; i < numval; i++)
                    ptr[i] = clamped_initval;
                checkvalint = ptr[0];
                break;
            }
            case PT_32BUI:
            {
                uint32_t *ptr = mem;
                uint32_t clamped_initval = rt_util_clamp_to_32BUI(initialvalue);
                for (i = 0; i < numval; i++)
                    ptr[i] = clamped_initval;
                checkvaluint = ptr[0];
                break;
            }
            case PT_32BF:
            {
                float *ptr = mem;
                float clamped_initval = rt_util_clamp_to_32F(initialvalue);
                for (i = 0; i < numval; i++)
                    ptr[i] = clamped_initval;
                checkvalfloat = ptr[0];
                break;
            }
            case PT_64BF:
            {
                double *ptr = mem;
                for (i = 0; i < numval; i++)
                    ptr[i] = initialvalue;
                checkvaldouble = ptr[0];
                break;
            }
            default:
            {
                rterror("rt_raster_generate_new_band: Unknown pixeltype %d", pixtype);
                rtdealloc(mem);
                return -1;
            }
        }
    }

    /* Overflow checking */
    rt_util_dbl_trunc_warning(
			initialvalue,
			checkvalint, checkvaluint,
			checkvalfloat, checkvaldouble,
			pixtype
		);

    band = rt_band_new_inline(width, height, pixtype, hasnodata, nodatavalue, mem);
    if (! band) {
        rterror("rt_raster_generate_new_band: Could not add band to raster. Aborting");
        rtdealloc(mem);
        return -1;
    }
    index = rt_raster_add_band(raster, band, index);
    numbands = rt_raster_get_num_bands(raster);
    if (numbands == oldnumbands || index == -1) {
        rterror("rt_raster_generate_new_band: Could not add band to raster. Aborting");
        rt_band_destroy(band);
    }

    return index;
}

/**
 * Get 6-element array of raster geotransform matrix
 *
 * @param raster : the raster to get matrix of
 * @param gt : output parameter, 6-element geotransform matrix
 *
 */
void
rt_raster_get_geotransform_matrix(rt_raster raster,
	double *gt) {
	assert(NULL != raster);
	assert(NULL != gt);

	gt[0] = raster->ipX;
	gt[1] = raster->scaleX;
	gt[2] = raster->skewX;
	gt[3] = raster->ipY;
	gt[4] = raster->skewY;
	gt[5] = raster->scaleY;
}

/**
 * Set raster's geotransform using 6-element array
 *
 * @param raster : the raster to set matrix of
 * @param gt : intput parameter, 6-element geotransform matrix
 *
 */
void
rt_raster_set_geotransform_matrix(rt_raster raster,
	double *gt) {
	assert(NULL != raster);
	assert(NULL != gt);

	raster->ipX = gt[0];
	raster->scaleX = gt[1];
	raster->skewX = gt[2];
	raster->ipY = gt[3];
	raster->skewY = gt[4];
	raster->scaleY = gt[5];
}

/**
 * Convert an xr, yr raster point to an xw, yw point on map
 *
 * @param raster : the raster to get info from
 * @param xr : the pixel's column
 * @param yr : the pixel's row
 * @param xw : output parameter, X ordinate of the geographical point
 * @param yw : output parameter, Y ordinate of the geographical point
 * @param gt : input/output parameter, 3x2 geotransform matrix
 *
 * @return if zero, error occurred in function
 */
int
rt_raster_cell_to_geopoint(rt_raster raster,
	double xr, double yr,
	double *xw, double *yw,
	double *gt
) {
	double *_gt = NULL;
	int init_gt = 0;
	int i = 0;

	assert(NULL != raster);
	assert(NULL != xw);
	assert(NULL != yw);

	if (NULL == gt) {
		_gt = rtalloc(sizeof(double) * 6);
		if (NULL == _gt) {
			rterror("rt_raster_cell_to_geopoint: Unable to allocate memory for geotransform matrix");
			return 0;
		}
		init_gt = 1;

		for (i = 0; i < 6; i++) _gt[i] = 0;
	}
	else {
		_gt = gt;
		init_gt = 0;
	}

	/* scale of matrix is not set */
	if (
		FLT_EQ(_gt[1], 0) ||
		FLT_EQ(_gt[5], 0)
	) {
		rt_raster_get_geotransform_matrix(raster, _gt);
	}

	RASTER_DEBUGF(4, "gt = (%f, %f, %f, %f, %f, %f)",
		_gt[0],
		_gt[1],
		_gt[2],
		_gt[3],
		_gt[4],
		_gt[5]
	);

	GDALApplyGeoTransform(_gt, xr, yr, xw, yw);
	RASTER_DEBUGF(4, "GDALApplyGeoTransform (c -> g) for (%f, %f) = (%f, %f)",
		xr, yr, *xw, *yw);

	if (init_gt) rtdealloc(_gt);
	return 1;
}

/**
 * Convert an xw,yw map point to a xr,yr raster point
 *
 * @param raster : the raster to get info from
 * @param xw : X ordinate of the geographical point
 * @param yw : Y ordinate of the geographical point
 * @param xr : output parameter, the pixel's column
 * @param yr : output parameter, the pixel's row
 * @param igt : input/output parameter, 3x2 inverse geotransform matrix
 *
 * @return if zero, error occurred in function
 */
int
rt_raster_geopoint_to_cell(rt_raster raster,
	double xw, double yw,
	double *xr, double *yr,
	double *igt
) {
	double *_igt = NULL;
	int i = 0;
	int init_igt = 0;
	double rnd = 0;

	assert(NULL != raster);
	assert(NULL != xr);
	assert(NULL != yr);

	if (igt == NULL) {
		_igt = rtalloc(sizeof(double) * 6);
		if (_igt == NULL) {
			rterror("rt_raster_geopoint_to_cell: Unable to allocate memory for inverse geotransform matrix");
			return 0;
		}
		init_igt = 1;

		for (i = 0; i < 6; i++) _igt[i] = 0;
	}
	else {
		_igt = igt;
		init_igt = 0;
	}

	/* matrix is not set */
	if (
		FLT_EQ(_igt[0], 0.) &&
		FLT_EQ(_igt[1], 0.) &&
		FLT_EQ(_igt[2], 0.) &&
		FLT_EQ(_igt[3], 0.) &&
		FLT_EQ(_igt[4], 0.) &&
		FLT_EQ(_igt[5], 0.)
	) {
		double gt[6] = {0.0};
		rt_raster_get_geotransform_matrix(raster, gt);

		if (!GDALInvGeoTransform(gt, _igt)) {
			rterror("rt_raster_geopoint_to_cell: Unable to compute inverse geotransform matrix");
			if (init_igt) rtdealloc(_igt);
			return 0;
		}
	}

	GDALApplyGeoTransform(_igt, xw, yw, xr, yr);
	RASTER_DEBUGF(4, "GDALApplyGeoTransform (g -> c) for (%f, %f) = (%f, %f)",
		xw, yw, *xr, *yr);

	rnd = ROUND(*xr, 0);
	if (FLT_EQ(rnd, *xr))
		*xr = rnd;
	else
		*xr = floor(*xr);

	rnd = ROUND(*yr, 0);
	if (FLT_EQ(rnd, *yr))
		*yr = rnd;
	else
		*yr = floor(*yr);

	RASTER_DEBUGF(4, "Corrected GDALApplyGeoTransform (g -> c) for (%f, %f) = (%f, %f)",
		xw, yw, *xr, *yr);

	if (init_igt) rtdealloc(_igt);
	return 1;
}

/**
 * Returns a set of "geomval" value, one for each group of pixel
 * sharing the same value for the provided band.
 *
 * A "geomval" value is a complex type composed of a geometry 
 * in LWPOLY representation (one for each group of pixel sharing
 * the same value) and the value associated with this geometry.
 *
 * @param raster: the raster to get info from.
 * @param nband: the band to polygonize. 0-based
 *
 * @return A set of "geomval" values, one for each group of pixels
 * sharing the same value for the provided band. The returned values are
 * LWPOLY geometries.
 */
rt_geomval
rt_raster_gdal_polygonize(
	rt_raster raster, int nband,
	int *pnElements
) {
	CPLErr cplerr = CE_None;
	char *pszQuery;
	long j;
	OGRSFDriverH ogr_drv = NULL;
	GDALDriverH gdal_drv = NULL;
	GDALDatasetH memdataset = NULL;
	GDALRasterBandH gdal_band = NULL;
	OGRDataSourceH memdatasource = NULL;
	rt_geomval pols = NULL;
	OGRLayerH hLayer = NULL;
	OGRFeatureH hFeature = NULL;
	OGRGeometryH hGeom = NULL;
	OGRFieldDefnH hFldDfn = NULL;
	unsigned char *wkb = NULL;
	int wkbsize = 0;
	LWGEOM *lwgeom = NULL;
	int nFeatureCount = 0;
	rt_band band = NULL;
	int iPixVal = -1;
	double dValue = 0.0;
	int iBandHasNodataValue = FALSE;
	double dBandNoData = 0.0;

	/* for checking that a geometry is valid */
	GEOSGeometry *ggeom = NULL;
	int isValid;
	LWGEOM *lwgeomValid = NULL;

#if POSTGIS_GEOS_VERSION < 33
	int msgValid = 0;
#endif

	uint32_t bandNums[1] = {nband};

	/* checks */
	assert(NULL != raster);
	assert(nband >= 0 && nband < rt_raster_get_num_bands(raster));

	RASTER_DEBUG(2, "In rt_raster_gdal_polygonize");

	/*******************************
	 * Get band
	 *******************************/
	band = rt_raster_get_band(raster, nband);
	if (NULL == band) {
		rterror("rt_raster_gdal_polygonize: Error getting band %d from raster", nband);
		return NULL;
	}

	iBandHasNodataValue = rt_band_get_hasnodata_flag(band);
	if (iBandHasNodataValue) dBandNoData = rt_band_get_nodata(band);

	/*****************************************************
	 * Convert raster to GDAL MEM dataset
	 *****************************************************/
	memdataset = rt_raster_to_gdal_mem(raster, NULL, bandNums, 1, &gdal_drv);
	if (NULL == memdataset) {
		rterror("rt_raster_gdal_polygonize: Couldn't convert raster to GDAL MEM dataset");
		return NULL;
	}

	/*****************************
	 * Register ogr mem driver
	 *****************************/
	OGRRegisterAll();

	RASTER_DEBUG(3, "creating OGR MEM vector");

	/*****************************************************
	 * Create an OGR in-memory vector for layers
	 *****************************************************/
	ogr_drv = OGRGetDriverByName("Memory");
	memdatasource = OGR_Dr_CreateDataSource(ogr_drv, "", NULL);
	if (NULL == memdatasource) {
		rterror("rt_raster_gdal_polygonize: Couldn't create a OGR Datasource to store pols");
		GDALClose(memdataset);
		return NULL;
	}

	/* Can MEM driver create new layers? */
	if (!OGR_DS_TestCapability(memdatasource, ODsCCreateLayer)) {
		rterror("rt_raster_gdal_polygonize: MEM driver can't create new layers, aborting");

		/* xxx jorgearevalo: what should we do now? */
		GDALClose(memdataset);
		OGRReleaseDataSource(memdatasource);

		return NULL;
	}

	RASTER_DEBUG(3, "polygonizying GDAL MEM raster band");

	/*****************************
	 * Polygonize the raster band
	 *****************************/

	/**
	 * From GDALPolygonize function header: "Polygon features will be
	 * created on the output layer, with polygon geometries representing
	 * the polygons". So,the WKB geometry type should be "wkbPolygon"
	 **/
	hLayer = OGR_DS_CreateLayer(memdatasource, "PolygonizedLayer", NULL, wkbPolygon, NULL);

	if (NULL == hLayer) {
		rterror("rt_raster_gdal_polygonize: Couldn't create layer to store polygons");

		GDALClose(memdataset);
		OGRReleaseDataSource(memdatasource);

		return NULL;
	}

	/**
	 * Create a new field in the layer, to store the px value
	 */

	/* First, create a field definition to create the field */
	hFldDfn = OGR_Fld_Create("PixelValue", OFTReal);

	/* Second, create the field */
	if (OGR_L_CreateField(hLayer, hFldDfn, TRUE) != OGRERR_NONE) {
		rtwarn("Couldn't create a field in OGR Layer. The polygons generated won't be able to store the pixel value");
		iPixVal = -1;
	}
	else {
		/* Index to the new field created in the layer */
		iPixVal = 0;
	}

	/* Get GDAL raster band */
	gdal_band = GDALGetRasterBand(memdataset, 1);
	if (NULL == gdal_band) {
		rterror("rt_raster_gdal_polygonize: Couldn't get GDAL band to polygonize");

		GDALClose(memdataset);
		OGR_Fld_Destroy(hFldDfn);
		OGR_DS_DeleteLayer(memdatasource, 0);
		OGRReleaseDataSource(memdatasource);
		
		return NULL;
	}

	/**
	 * We don't need a raster mask band. Each band has a nodata value.
	 **/
#ifdef GDALFPOLYGONIZE
	cplerr = GDALFPolygonize(gdal_band, NULL, hLayer, iPixVal, NULL, NULL, NULL);
#else
	cplerr = GDALPolygonize(gdal_band, NULL, hLayer, iPixVal, NULL, NULL, NULL);
#endif

	if (cplerr != CE_None) {
		rterror("rt_raster_gdal_polygonize: Could not polygonize GDAL band");

		GDALClose(memdataset);
		OGR_Fld_Destroy(hFldDfn);
		OGR_DS_DeleteLayer(memdatasource, 0);
		OGRReleaseDataSource(memdatasource);

		return NULL;
	}

	/**
	 * Optimization: Apply a OGR SQL filter to the layer to select the
	 * features different from NODATA value.
	 *
	 * Thanks to David Zwarg.
	 **/
	if (iBandHasNodataValue) {
		pszQuery = (char *) rtalloc(50 * sizeof (char));
		sprintf(pszQuery, "PixelValue != %f", dBandNoData );
		OGRErr e = OGR_L_SetAttributeFilter(hLayer, pszQuery);
		if (e != OGRERR_NONE) {
			rtwarn("Error filtering NODATA values for band. All values will be treated as data values");
		}
	}
	else {
		pszQuery = NULL;
	}

	/*********************************************************************
	 * Transform OGR layers to WKB polygons
	 * XXX jorgearevalo: GDALPolygonize does not set the coordinate system
	 * on the output layer. Application code should do this when the layer
	 * is created, presumably matching the raster coordinate system.
	 *********************************************************************/
	nFeatureCount = OGR_L_GetFeatureCount(hLayer, TRUE);

	/* Allocate memory for pols */
	pols = (rt_geomval) rtalloc(nFeatureCount * sizeof(struct rt_geomval_t));

	if (NULL == pols) {
		rterror("rt_raster_gdal_polygonize: Could not allocate memory for geomval set");

		GDALClose(memdataset);
		OGR_Fld_Destroy(hFldDfn);
		OGR_DS_DeleteLayer(memdatasource, 0);
		if (NULL != pszQuery)
			rtdealloc(pszQuery);
		OGRReleaseDataSource(memdatasource);

		return NULL;
	}

	/* initialize GEOS */
	initGEOS(lwnotice, lwgeom_geos_error);

	RASTER_DEBUGF(3, "storing polygons (%d)", nFeatureCount);

	if (pnElements)
		*pnElements = 0;

	/* Reset feature reading to start in the first feature */
	OGR_L_ResetReading(hLayer);

	for (j = 0; j < nFeatureCount; j++) {
		hFeature = OGR_L_GetNextFeature(hLayer);
		dValue = OGR_F_GetFieldAsDouble(hFeature, iPixVal);

		hGeom = OGR_F_GetGeometryRef(hFeature);
		wkbsize = OGR_G_WkbSize(hGeom);

		/* allocate wkb buffer */
		wkb = rtalloc(sizeof(unsigned char) * wkbsize);
		if (wkb == NULL) {
			rterror("rt_raster_gdal_polygonize: Could not allocate memory for WKB buffer");

			OGR_F_Destroy(hFeature);
			GDALClose(memdataset);
			OGR_Fld_Destroy(hFldDfn);
			OGR_DS_DeleteLayer(memdatasource, 0);
			if (NULL != pszQuery)
				rtdealloc(pszQuery);
			OGRReleaseDataSource(memdatasource);

			return NULL;
		}

		/* export WKB with LSB byte order */
		OGR_G_ExportToWkb(hGeom, wkbNDR, wkb);

		/* convert WKB to LWGEOM */
		lwgeom = lwgeom_from_wkb(wkb, wkbsize, LW_PARSER_CHECK_NONE);

		/* cleanup unnecessary stuff */
		rtdealloc(wkb);
		wkb = NULL;
		wkbsize = 0;

		OGR_F_Destroy(hFeature);

		/* specify SRID */
		lwgeom_set_srid(lwgeom, rt_raster_get_srid(raster));

		/*
			is geometry valid?
			if not, try to make valid
		*/
		do {
#if POSTGIS_GEOS_VERSION < 33
/*
			if (!msgValid) {
				rtwarn("Skipping check for invalid geometry.  GEOS-3.3.0 or up is required to fix an invalid geometry");
				msgValid = 1;
			}
*/
			break;
#endif

			ggeom = (GEOSGeometry *) LWGEOM2GEOS(lwgeom);
			if (ggeom == NULL) {
				rtwarn("Cannot test geometry for validity");
				break;
			}

			isValid = GEOSisValid(ggeom);

			GEOSGeom_destroy(ggeom);
			ggeom = NULL;

			/* geometry is valid */
			if (isValid)
				break;

			/* make geometry valid */
			lwgeomValid = lwgeom_make_valid(lwgeom);
			if (lwgeomValid == NULL) {
				rtwarn("Cannot fix invalid geometry");
				break;
			}

			lwgeom_free(lwgeom);
			lwgeom = lwgeomValid;
		}
		while (0);

		/* save lwgeom */
		pols[j].geom = lwgeom_as_lwpoly(lwgeom);

		/* set pixel value */
		pols[j].val = dValue;
	}

	if (pnElements)
		*pnElements = nFeatureCount;

	RASTER_DEBUG(3, "destroying GDAL MEM raster");
	GDALClose(memdataset);

	RASTER_DEBUG(3, "destroying OGR MEM vector");
	OGR_Fld_Destroy(hFldDfn);
	OGR_DS_DeleteLayer(memdatasource, 0);
	if (NULL != pszQuery) rtdealloc(pszQuery);
	OGRReleaseDataSource(memdatasource);

	return pols;
}

LWPOLY*
rt_raster_get_convex_hull(rt_raster raster) {
		double gt[6] = {0.0};
    POINTARRAY **rings = NULL;
    POINTARRAY *pts = NULL;
    LWPOLY* ret = NULL;
    POINT4D p4d;

    assert(NULL != raster);

    RASTER_DEBUGF(3, "rt_raster_get_convex_hull: raster is %dx%d",
            raster->width, raster->height);

    if ((!raster->width) || (!raster->height)) {
        return 0;
    }

    rings = (POINTARRAY **) rtalloc(sizeof (POINTARRAY*));
    if (!rings) {
        rterror("rt_raster_get_convex_hull: Out of memory [%s:%d]", __FILE__, __LINE__);
        return 0;
    }
    rings[0] = ptarray_construct(0, 0, 5);
    /* TODO: handle error on ptarray construction */
    /* XXX jorgearevalo: the error conditions aren't managed in ptarray_construct */
    if (!rings[0]) {
        rterror("rt_raster_get_convex_hull: Out of memory [%s:%d]", __FILE__, __LINE__);
        return 0;
    }
    pts = rings[0];

    /* Upper-left corner (first and last points) */
    rt_raster_cell_to_geopoint(raster,
            0, 0,
            &p4d.x, &p4d.y,
						gt);
    ptarray_set_point4d(pts, 0, &p4d);
    ptarray_set_point4d(pts, 4, &p4d); /* needed for closing it? */

    /* Upper-right corner (we go clockwise) */
    rt_raster_cell_to_geopoint(raster,
            raster->width, 0,
            &p4d.x, &p4d.y,
						gt);
    ptarray_set_point4d(pts, 1, &p4d);

    /* Lower-right corner */
    rt_raster_cell_to_geopoint(raster,
            raster->width, raster->height,
            &p4d.x, &p4d.y,
						gt);
    ptarray_set_point4d(pts, 2, &p4d);

    /* Lower-left corner */
    rt_raster_cell_to_geopoint(raster,
            0, raster->height,
            &p4d.x, &p4d.y,
						gt);
    ptarray_set_point4d(pts, 3, &p4d);

    ret = lwpoly_construct(rt_raster_get_srid(raster), 0, 1, rings);

    return ret;
}

/**
 * Get raster's envelope.
 *
 * The envelope is the minimum bounding rectangle of the raster
 *
 * @param raster: the raster to get envelope of
 * @param env: pointer to rt_envelope
 *
 * @return 0 on error, 1 on success
 */
int rt_raster_get_envelope(
	rt_raster raster,
	rt_envelope *env
) {
	int i;
	int rtn;
	int set = 0;
	double _r[2] = {0.};
	double _w[2] = {0.};
	double _gt[6] = {0.};

	assert(raster != NULL);
	assert(env != NULL);

	rt_raster_get_geotransform_matrix(raster, _gt);

	for (i = 0; i < 4; i++) {
		switch (i) {
			case 0:
				_r[0] = 0;
				_r[1] = 0;
				break;
			case 1:
				_r[0] = 0;
				_r[1] = raster->height;
				break;
			case 2:
				_r[0] = raster->width;
				_r[1] = raster->height;
				break;
			case 3:
				_r[0] = raster->width;
				_r[1] = 0;
				break;
		}

		rtn = rt_raster_cell_to_geopoint(
			raster,
			_r[0], _r[1],
			&(_w[0]), &(_w[1]),
			_gt
		);
		if (!rtn) {
			rterror("rt_raster_get_envelope: Unable to compute spatial coordinates for raster pixel");
			return 0;
		}

		if (!set) {
			set = 1;
			env->MinX = _w[0];
			env->MaxX = _w[0];
			env->MinY = _w[1];
			env->MaxY = _w[1];
		}
		else {
			if (_w[0] < env->MinX)
				env->MinX = _w[0];
			else if (_w[0] > env->MaxX)
				env->MaxX = _w[0];

			if (_w[1] < env->MinY)
				env->MinY = _w[1];
			else if (_w[1] > env->MaxY)
				env->MaxY = _w[1];
		}
	}

	return 1;
}

/*
 * Compute skewed extent that covers unskewed extent.
 *
 * @param envelope: unskewed extent of type rt_envelope
 * @param skew: pointer to 2-element array (x, y) of skew
 * @param scale: pointer to 2-element array (x, y) of scale
 * @param tolerance: value between 0 and 1 where the smaller the tolerance
 *                   results in an extent approaching the "minimum" skewed
 *                   extent.  If value <= 0, tolerance = 0.1.
 *                   If value > 1, tolerance = 1.
 *
 * @return skewed raster who's extent covers unskewed extent, NULL on error
 */
rt_raster
rt_raster_compute_skewed_raster(
	rt_envelope extent,
	double *skew,
	double *scale,
	double tolerance
) {
	uint32_t run = 0;
	uint32_t max_run = 1;
	double dbl_run = 0;

	int rtn;
	int covers = 0;
	rt_raster raster;
	double _gt[6] = {0};
	double _igt[6] = {0};
	int _d[2] = {1, -1};
	int _dlast = 0;
	int _dlastpos = 0;
	double _w[2] = {0};
	double _r[2] = {0};
	double _xy[2] = {0};
	int i;
	int j;
	int x;
	int y;

	LWPOLY *spoly = NULL;
	GEOSGeometry *sgeom = NULL;
	GEOSGeometry *ngeom = NULL;

	if (
		(tolerance < 0.) ||
		FLT_EQ(tolerance, 0.)
	) {
		tolerance = 0.1;
	}
	else if (tolerance > 1.)
		tolerance = 1;

	dbl_run = tolerance;
	while (dbl_run < 10) {
		dbl_run *= 10.;
		max_run *= 10;
	}

	/* scale must be provided */
	if (scale == NULL)
		return NULL;
	for (i = 0; i < 2; i++) {
		if (FLT_EQ(scale[i], 0)) {
			rterror("rt_raster_compute_skewed_raster: Scale cannot be zero");
			return 0;
		}

		if (i < 1)
			_gt[1] = fabs(scale[i] * tolerance);
		else
			_gt[5] = fabs(scale[i] * tolerance);
	}
	/* conform scale-y to be negative */
	_gt[5] *= -1;

	/* skew not provided or skew is zero, return raster of correct dim and spatial attributes */
	if (
		(skew == NULL) || (
			FLT_EQ(skew[0], 0) &&
			FLT_EQ(skew[1], 0)
		)
	) {
		int _dim[2] = {
			(int) fmax((fabs(extent.MaxX - extent.MinX) + (fabs(scale[0]) / 2.)) / fabs(scale[0]), 1),
			(int) fmax((fabs(extent.MaxY - extent.MinY) + (fabs(scale[1]) / 2.)) / fabs(scale[1]), 1)
		};

		raster = rt_raster_new(_dim[0], _dim[1]);
		if (raster == NULL) {
			rterror("rt_raster_compute_skewed_raster: Unable to create output raster");
			return NULL;
		}

		rt_raster_set_offsets(raster, extent.MinX, extent.MaxY);
		rt_raster_set_scale(raster, fabs(scale[0]), -1 * fabs(scale[1]));
		rt_raster_set_skews(raster, skew[0], skew[1]);

		return raster;
	}

	/* direction to shift upper-left corner */
	if (skew[0] > 0.)
		_d[0] = -1;
	if (skew[1] < 0.)
		_d[1] = 1;

	/* geotransform */
	_gt[0] = extent.UpperLeftX;
	_gt[2] = skew[0] * tolerance;
	_gt[3] = extent.UpperLeftY;
	_gt[4] = skew[1] * tolerance;

	RASTER_DEBUGF(4, "Initial geotransform: %f, %f, %f, %f, %f, %f",
		_gt[0], _gt[1], _gt[2], _gt[3], _gt[4], _gt[5]
	);
	RASTER_DEBUGF(4, "Delta: %d, %d", _d[0], _d[1]);

	/* simple raster */
	if ((raster = rt_raster_new(1, 1)) == NULL) {
		rterror("rt_raster_compute_skewed_raster: Out of memory allocating extent raster");
		return NULL;
	}
	rt_raster_set_geotransform_matrix(raster, _gt);

	/* get inverse geotransform matrix */
	if (!GDALInvGeoTransform(_gt, _igt)) {
		rterror("rt_raster_compute_skewed_raster: Unable to compute inverse geotransform matrix");
		rt_raster_destroy(raster);
		return NULL;
	}
	RASTER_DEBUGF(4, "Inverse geotransform: %f, %f, %f, %f, %f, %f",
		_igt[0], _igt[1], _igt[2], _igt[3], _igt[4], _igt[5]
	);

	/* shift along axis */
	for (i = 0; i < 2; i++) {
		covers = 0;
		run = 0;

		RASTER_DEBUGF(3, "Shifting along %s axis", i < 1 ? "X" : "Y");

		do {

			/* prevent possible infinite loop */
			if (run > max_run) {
				rterror("rt_raster_compute_skewed_raster: Unable to compute skewed extent due to check preventing infinite loop");
				rt_raster_destroy(raster);
				return NULL;
			}

			/*
				check the four corners that they are covered along the specific axis
				pixel column should be >= 0
			*/
			for (j = 0; j < 4; j++) {
				switch (j) {
					/* upper-left */
					case 0:
						_xy[0] = extent.MinX;
						_xy[1] = extent.MaxY;
						break;
					/* lower-left */
					case 1:
						_xy[0] = extent.MinX;
						_xy[1] = extent.MinY;
						break;
					/* lower-right */
					case 2:
						_xy[0] = extent.MaxX;
						_xy[1] = extent.MinY;
						break;
					/* upper-right */
					case 3:
						_xy[0] = extent.MaxX;
						_xy[1] = extent.MaxY;
						break;
				}

				rtn = rt_raster_geopoint_to_cell(
					raster,
					_xy[0], _xy[1],
					&(_r[0]), &(_r[1]),
					_igt
				);
				if (!rtn) {
					rterror("rt_raster_compute_skewed_raster: Unable to compute raster pixel for spatial coordinates");
					rt_raster_destroy(raster);
					return NULL;
				}

				RASTER_DEBUGF(4, "Point %d at cell %d x %d", j, (int) _r[0], (int) _r[1]);

				/* raster doesn't cover point */
				if ((int) _r[i] < 0) {
					RASTER_DEBUGF(4, "Point outside of skewed extent: %d", j);
					covers = 0;

					if (_dlastpos != j) {
						_dlast = (int) _r[i];
						_dlastpos = j;
					}
					else if ((int) _r[i] < _dlast) {
						RASTER_DEBUG(4, "Point going in wrong direction.  Reversing direction");
						_d[i] *= -1;
						_dlastpos = -1;
						run = 0;
					}

					break;
				}

				covers++;
			}

			if (!covers) {
				x = 0;
				y = 0;
				if (i < 1)
					x = _d[i] * fabs(_r[i]);
				else
					y = _d[i] * fabs(_r[i]);

				rtn = rt_raster_cell_to_geopoint(
					raster,
					x, y,
					&(_w[0]), &(_w[1]),
					_gt
				);
				if (!rtn) {
					rterror("rt_raster_compute_skewed_raster: Unable to compute spatial coordinates for raster pixel");
					rt_raster_destroy(raster);
					return NULL;
				}

				/* adjust ul */
				if (i < 1)
					_gt[0] = _w[i];
				else
					_gt[3] = _w[i];
				rt_raster_set_geotransform_matrix(raster, _gt);
				RASTER_DEBUGF(4, "Shifted geotransform: %f, %f, %f, %f, %f, %f",
					_gt[0], _gt[1], _gt[2], _gt[3], _gt[4], _gt[5]
				);

				/* get inverse geotransform matrix */
				if (!GDALInvGeoTransform(_gt, _igt)) {
					rterror("rt_raster_compute_skewed_raster: Unable to compute inverse geotransform matrix");
					rt_raster_destroy(raster);
					return NULL;
				}
				RASTER_DEBUGF(4, "Inverse geotransform: %f, %f, %f, %f, %f, %f",
					_igt[0], _igt[1], _igt[2], _igt[3], _igt[4], _igt[5]
				);
			}

			run++;
		}
		while (!covers);
	}

	/* covers test */
	rtn = rt_raster_geopoint_to_cell(
		raster,
		extent.MaxX, extent.MinY,
		&(_r[0]), &(_r[1]),
		_igt
	);
	if (!rtn) {
		rterror("rt_raster_compute_skewed_raster: Unable to compute raster pixel for spatial coordinates");
		rt_raster_destroy(raster);
		return NULL;
	}

	RASTER_DEBUGF(4, "geopoint %f x %f at cell %d x %d", extent.MaxX, extent.MinY, (int) _r[0], (int) _r[1]);

	raster->width = _r[0];
	raster->height = _r[1];

	/* initialize GEOS */
	initGEOS(lwnotice, lwgeom_geos_error);

	/* create reference LWPOLY */
	{
		LWPOLY *npoly = rt_util_envelope_to_lwpoly(extent);
		if (npoly == NULL) {
			rterror("rt_raster_compute_skewed_raster: Unable to build extent's geometry for covers test");
			rt_raster_destroy(raster);
			return NULL;
		}

		ngeom = (GEOSGeometry *) LWGEOM2GEOS(lwpoly_as_lwgeom(npoly));
		lwpoly_free(npoly);
	}

	do {
		covers = 0;

		/* construct spoly from raster */
		spoly = rt_raster_get_convex_hull(raster);
		if (spoly == NULL) {
			rterror("rt_raster_compute_skewed_raster: Unable to build skewed extent's geometry for covers test");
			GEOSGeom_destroy(ngeom);
			rt_raster_destroy(raster);
			return NULL;
		}

		sgeom = (GEOSGeometry *) LWGEOM2GEOS(lwpoly_as_lwgeom(spoly));
		lwpoly_free(spoly);

		covers = GEOSRelatePattern(sgeom, ngeom, "******FF*");
		GEOSGeom_destroy(sgeom);

		if (covers == 2) {
			rterror("rt_raster_compute_skewed_raster: Unable to run covers test");
			GEOSGeom_destroy(ngeom);
			rt_raster_destroy(raster);
			return NULL;
		}

		if (covers)
			break;

		raster->width++;
		raster->height++;
	}
	while (!covers);

	RASTER_DEBUGF(4, "Skewed extent does cover normal extent with dimensions %d x %d", raster->width, raster->height);

	raster->width = (int) ((((double) raster->width) * fabs(_gt[1]) + fabs(scale[0] / 2.)) / fabs(scale[0]));
	raster->height = (int) ((((double) raster->height) * fabs(_gt[5]) + fabs(scale[1] / 2.)) / fabs(scale[1]));
	_gt[1] = fabs(scale[0]);
	_gt[5] = -1 * fabs(scale[1]);
	_gt[2] = skew[0];
	_gt[4] = skew[1];
	rt_raster_set_geotransform_matrix(raster, _gt);

	/* minimize width/height */
	for (i = 0; i < 2; i++) {
		covers = 1;
		do {
			if (i < 1)
				raster->width--;
			else
				raster->height--;
			
			/* construct spoly from raster */
			spoly = rt_raster_get_convex_hull(raster);
			if (spoly == NULL) {
				rterror("rt_raster_compute_skewed_raster: Unable to build skewed extent's geometry for minimizing dimensions");
				GEOSGeom_destroy(ngeom);
				rt_raster_destroy(raster);
				return NULL;
			}

			sgeom = (GEOSGeometry *) LWGEOM2GEOS(lwpoly_as_lwgeom(spoly));
			lwpoly_free(spoly);

			covers = GEOSRelatePattern(sgeom, ngeom, "******FF*");
			GEOSGeom_destroy(sgeom);

			if (covers == 2) {
				rterror("rt_raster_compute_skewed_raster: Unable to run covers test for minimizing dimensions");
				GEOSGeom_destroy(ngeom);
				rt_raster_destroy(raster);
				return NULL;
			}

			if (!covers) {
				if (i < 1)
					raster->width++;
				else
					raster->height++;

				break;
			}
		}
		while (covers);
	}

	GEOSGeom_destroy(ngeom);

	return raster;
}

/*--------- WKB I/O ---------------------------------------------------*/

static uint8_t
isMachineLittleEndian(void) {
    static int endian_check_int = 1; /* dont modify this!!! */
    /* 0=big endian|xdr --  1=little endian|ndr */
    return *((uint8_t *) & endian_check_int);
}

static uint8_t
read_uint8(const uint8_t** from) {
    assert(NULL != from);

    return *(*from)++;
}

/* unused up to now
static void
write_uint8(uint8_t** from, uint8_t v)
{
    assert(NULL != from);

 *(*from)++ = v;
}
 */

static int8_t
read_int8(const uint8_t** from) {
    assert(NULL != from);

    return (int8_t) read_uint8(from);
}

/* unused up to now
static void
write_int8(uint8_t** from, int8_t v)
{
    assert(NULL != from);

 *(*from)++ = v;
}
 */

static uint16_t
read_uint16(const uint8_t** from, uint8_t littleEndian) {
    uint16_t ret = 0;

    assert(NULL != from);

    if (littleEndian) {
        ret = (*from)[0] |
                (*from)[1] << 8;
    } else {
        /* big endian */
        ret = (*from)[0] << 8 |
                (*from)[1];
    }
    *from += 2;
    return ret;
}

static void
write_uint16(uint8_t** to, uint8_t littleEndian, uint16_t v) {
    assert(NULL != to);

    if (littleEndian) {
        (*to)[0] = v & 0x00FF;
        (*to)[1] = v >> 8;
    } else {
        (*to)[1] = v & 0x00FF;
        (*to)[0] = v >> 8;
    }
    *to += 2;
}

static int16_t
read_int16(const uint8_t** from, uint8_t littleEndian) {
    assert(NULL != from);

    return read_uint16(from, littleEndian);
}

/* unused up to now
static void
write_int16(uint8_t** to, uint8_t littleEndian, int16_t v)
{
    assert(NULL != to);

    if ( littleEndian )
    {
        (*to)[0] = v & 0x00FF;
        (*to)[1] = v >> 8;
    }
    else
    {
        (*to)[1] = v & 0x00FF;
        (*to)[0] = v >> 8;
    }
 *to += 2;
}
 */

static uint32_t
read_uint32(const uint8_t** from, uint8_t littleEndian) {
    uint32_t ret = 0;

    assert(NULL != from);

    if (littleEndian) {
        ret = (uint32_t) ((*from)[0] & 0xff) |
                (uint32_t) ((*from)[1] & 0xff) << 8 |
                (uint32_t) ((*from)[2] & 0xff) << 16 |
                (uint32_t) ((*from)[3] & 0xff) << 24;
    } else {
        /* big endian */
        ret = (uint32_t) ((*from)[3] & 0xff) |
                (uint32_t) ((*from)[2] & 0xff) << 8 |
                (uint32_t) ((*from)[1] & 0xff) << 16 |
                (uint32_t) ((*from)[0] & 0xff) << 24;
    }

    *from += 4;
    return ret;
}

/* unused up to now
static void
write_uint32(uint8_t** to, uint8_t littleEndian, uint32_t v)
{
    assert(NULL != to);

    if ( littleEndian )
    {
        (*to)[0] = v & 0x000000FF;
        (*to)[1] = ( v & 0x0000FF00 ) >> 8;
        (*to)[2] = ( v & 0x00FF0000 ) >> 16;
        (*to)[3] = ( v & 0xFF000000 ) >> 24;
    }
    else
    {
        (*to)[3] = v & 0x000000FF;
        (*to)[2] = ( v & 0x0000FF00 ) >> 8;
        (*to)[1] = ( v & 0x00FF0000 ) >> 16;
        (*to)[0] = ( v & 0xFF000000 ) >> 24;
    }
 *to += 4;
}
 */

static int32_t
read_int32(const uint8_t** from, uint8_t littleEndian) {
    assert(NULL != from);

    return read_uint32(from, littleEndian);
}

/* unused up to now
static void
write_int32(uint8_t** to, uint8_t littleEndian, int32_t v)
{
    assert(NULL != to);

    if ( littleEndian )
    {
        (*to)[0] = v & 0x000000FF;
        (*to)[1] = ( v & 0x0000FF00 ) >> 8;
        (*to)[2] = ( v & 0x00FF0000 ) >> 16;
        (*to)[3] = ( v & 0xFF000000 ) >> 24;
    }
    else
    {
        (*to)[3] = v & 0x000000FF;
        (*to)[2] = ( v & 0x0000FF00 ) >> 8;
        (*to)[1] = ( v & 0x00FF0000 ) >> 16;
        (*to)[0] = ( v & 0xFF000000 ) >> 24;
    }
 *to += 4;
}
 */

static float
read_float32(const uint8_t** from, uint8_t littleEndian) {

    union {
        float f;
        uint32_t i;
    } ret;

    ret.i = read_uint32(from, littleEndian);

    return ret.f;
}

/* unused up to now
static void
write_float32(uint8_t** from, uint8_t littleEndian, float f)
{
    union {
        float f;
        uint32_t i;
    } u;

    u.f = f;
    write_uint32(from, littleEndian, u.i);
}
 */

static double
read_float64(const uint8_t** from, uint8_t littleEndian) {

    union {
        double d;
        uint64_t i;
    } ret;

    assert(NULL != from);

    if (littleEndian) {
        ret.i = (uint64_t) ((*from)[0] & 0xff) |
                (uint64_t) ((*from)[1] & 0xff) << 8 |
                (uint64_t) ((*from)[2] & 0xff) << 16 |
                (uint64_t) ((*from)[3] & 0xff) << 24 |
                (uint64_t) ((*from)[4] & 0xff) << 32 |
                (uint64_t) ((*from)[5] & 0xff) << 40 |
                (uint64_t) ((*from)[6] & 0xff) << 48 |
                (uint64_t) ((*from)[7] & 0xff) << 56;
    } else {
        /* big endian */
        ret.i = (uint64_t) ((*from)[7] & 0xff) |
                (uint64_t) ((*from)[6] & 0xff) << 8 |
                (uint64_t) ((*from)[5] & 0xff) << 16 |
                (uint64_t) ((*from)[4] & 0xff) << 24 |
                (uint64_t) ((*from)[3] & 0xff) << 32 |
                (uint64_t) ((*from)[2] & 0xff) << 40 |
                (uint64_t) ((*from)[1] & 0xff) << 48 |
                (uint64_t) ((*from)[0] & 0xff) << 56;
    }

    *from += 8;
    return ret.d;
}

/* unused up to now
static void
write_float64(uint8_t** to, uint8_t littleEndian, double v)
{
    union {
        double d;
        uint64_t i;
    } u;

    assert(NULL != to);

    u.d = v;

    if ( littleEndian )
    {
        (*to)[0] =   u.i & 0x00000000000000FFULL;
        (*to)[1] = ( u.i & 0x000000000000FF00ULL ) >> 8;
        (*to)[2] = ( u.i & 0x0000000000FF0000ULL ) >> 16;
        (*to)[3] = ( u.i & 0x00000000FF000000ULL ) >> 24;
        (*to)[4] = ( u.i & 0x000000FF00000000ULL ) >> 32;
        (*to)[5] = ( u.i & 0x0000FF0000000000ULL ) >> 40;
        (*to)[6] = ( u.i & 0x00FF000000000000ULL ) >> 48;
        (*to)[7] = ( u.i & 0xFF00000000000000ULL ) >> 56;
    }
    else
    {
        (*to)[7] =   u.i & 0x00000000000000FFULL;
        (*to)[6] = ( u.i & 0x000000000000FF00ULL ) >> 8;
        (*to)[5] = ( u.i & 0x0000000000FF0000ULL ) >> 16;
        (*to)[4] = ( u.i & 0x00000000FF000000ULL ) >> 24;
        (*to)[3] = ( u.i & 0x000000FF00000000ULL ) >> 32;
        (*to)[2] = ( u.i & 0x0000FF0000000000ULL ) >> 40;
        (*to)[1] = ( u.i & 0x00FF000000000000ULL ) >> 48;
        (*to)[0] = ( u.i & 0xFF00000000000000ULL ) >> 56;
    }
 *to += 8;
}
 */

#define BANDTYPE_FLAGS_MASK 0xF0
#define BANDTYPE_PIXTYPE_MASK 0x0F
#define BANDTYPE_FLAG_OFFDB     (1<<7)
#define BANDTYPE_FLAG_HASNODATA (1<<6)
#define BANDTYPE_FLAG_ISNODATA  (1<<5)
#define BANDTYPE_FLAG_RESERVED3 (1<<4)

#define BANDTYPE_PIXTYPE(x) ((x)&BANDTYPE_PIXTYPE_MASK)
#define BANDTYPE_IS_OFFDB(x) ((x)&BANDTYPE_FLAG_OFFDB)
#define BANDTYPE_HAS_NODATA(x) ((x)&BANDTYPE_FLAG_HASNODATA)
#define BANDTYPE_IS_NODATA(x) ((x)&BANDTYPE_FLAG_ISNODATA)

/* Read band from WKB as at start of band */
static rt_band
rt_band_from_wkb(uint16_t width, uint16_t height,
        const uint8_t** ptr, const uint8_t* end,
        uint8_t littleEndian) {
    rt_band band = NULL;
    int pixbytes = 0;
    uint8_t type = 0;
    unsigned long sz = 0;
    uint32_t v = 0;



    assert(NULL != ptr);
    assert(NULL != end);

    band = rtalloc(sizeof (struct rt_band_t));
    if (!band) {
        rterror("rt_band_from_wkb: Out of memory allocating rt_band during WKB parsing");
        return 0;
    }

    if (end - *ptr < 1) {
        rterror("rt_band_from_wkb: Premature end of WKB on band reading (%s:%d)",
                __FILE__, __LINE__);
        return 0;
    }
    type = read_uint8(ptr);

    if ((type & BANDTYPE_PIXTYPE_MASK) >= PT_END) {
        rterror("rt_band_from_wkb: Invalid pixtype %d", type & BANDTYPE_PIXTYPE_MASK);
        rtdealloc(band);
        return 0;
    }
    assert(NULL != band);

    band->pixtype = type & BANDTYPE_PIXTYPE_MASK;
    band->offline = BANDTYPE_IS_OFFDB(type) ? 1 : 0;
    band->hasnodata = BANDTYPE_HAS_NODATA(type) ? 1 : 0;
    band->isnodata = BANDTYPE_IS_NODATA(type) ? 1 : 0;
    band->width = width;
    band->height = height;

    RASTER_DEBUGF(3, " Band pixtype:%s, offline:%d, hasnodata:%d",
            rt_pixtype_name(band->pixtype),
            band->offline,
            band->hasnodata);

    /* Check there's enough bytes to read nodata value */

    pixbytes = rt_pixtype_size(band->pixtype);
    if (((*ptr) + pixbytes) >= end) {
        rterror("rt_band_from_wkb: Premature end of WKB on band novalue reading");
        rtdealloc(band);
        return 0;
    }

    /* Read nodata value */
    switch (band->pixtype) {
        case PT_1BB:
        {
            band->nodataval = ((int) read_uint8(ptr)) & 0x01;
            break;
        }
        case PT_2BUI:
        {
            band->nodataval = ((int) read_uint8(ptr)) & 0x03;
            break;
        }
        case PT_4BUI:
        {
            band->nodataval = ((int) read_uint8(ptr)) & 0x0F;
            break;
        }
        case PT_8BSI:
        {
            band->nodataval = read_int8(ptr);
            break;
        }
        case PT_8BUI:
        {
            band->nodataval = read_uint8(ptr);
            break;
        }
        case PT_16BSI:
        {
            band->nodataval = read_int16(ptr, littleEndian);
            break;
        }
        case PT_16BUI:
        {
            band->nodataval = read_uint16(ptr, littleEndian);
            break;
        }
        case PT_32BSI:
        {
            band->nodataval = read_int32(ptr, littleEndian);
            break;
        }
        case PT_32BUI:
        {
            band->nodataval = read_uint32(ptr, littleEndian);
            break;
        }
        case PT_32BF:
        {
            band->nodataval = read_float32(ptr, littleEndian);
            break;
        }
        case PT_64BF:
        {
            band->nodataval = read_float64(ptr, littleEndian);
            break;
        }
        default:
        {
            rterror("rt_band_from_wkb: Unknown pixeltype %d", band->pixtype);
            rtdealloc(band);
            return 0;
        }
    }

    RASTER_DEBUGF(3, " Nodata value: %g, pixbytes: %d, ptr @ %p, end @ %p",
            band->nodataval, pixbytes, *ptr, end);

    if (band->offline) {
        if (((*ptr) + 1) >= end) {
            rterror("rt_band_from_wkb: Premature end of WKB on offline "
                    "band data bandNum reading (%s:%d)",
                    __FILE__, __LINE__);
            rtdealloc(band);
            return 0;
        }
        band->data.offline.bandNum = read_int8(ptr);

        band->data.offline.mem = NULL;

        {
            /* check we have a NULL-termination */
            sz = 0;
            while ((*ptr)[sz] && &((*ptr)[sz]) < end) ++sz;
            if (&((*ptr)[sz]) >= end) {
                rterror("rt_band_from_wkb: Premature end of WKB on band offline path reading");
                rtdealloc(band);
                return 0;
            }

            band->ownsData = 1;
            band->data.offline.path = rtalloc(sz + 1);

            memcpy(band->data.offline.path, *ptr, sz);
            band->data.offline.path[sz] = '\0';

            RASTER_DEBUGF(3, "OFFDB band path is %s (size is %d)",
                    band->data.offline.path, sz);

            *ptr += sz + 1;

            /* TODO: How could we know if the offline band is a nodata band? */
            band->isnodata = FALSE;
        }
        return band;
    }

    /* This is an on-disk band */
    sz = width * height * pixbytes;
    if (((*ptr) + sz) > end) {
        rterror("rt_band_from_wkb: Premature end of WKB on band data reading (%s:%d)",
                __FILE__, __LINE__);
        rtdealloc(band);
        return 0;
    }

    band->data.mem = rtalloc(sz);
    if (!band->data.mem) {
        rterror("rt_band_from_wkb: Out of memory during band creation in WKB parser");
        rtdealloc(band);
        return 0;
    }

    memcpy(band->data.mem, *ptr, sz);
    *ptr += sz;

    /* Should now flip values if > 8bit and
     * littleEndian != isMachineLittleEndian */
    if (pixbytes > 1) {
        if (isMachineLittleEndian() != littleEndian) {
            {
                void (*flipper)(uint8_t*) = 0;
                uint8_t *flipme = NULL;

                if (pixbytes == 2) flipper = flip_endian_16;
                else if (pixbytes == 4) flipper = flip_endian_32;
                else if (pixbytes == 8) flipper = flip_endian_64;
                else {
                    rterror("rt_band_from_wkb: Unexpected pix bytes %d", pixbytes);
                    rtdealloc(band);
                    rtdealloc(band->data.mem);
                    return 0;
                }

                flipme = band->data.mem;
                sz = width * height;
                for (v = 0; v < sz; ++v) {
                    flipper(flipme);
                    flipme += pixbytes;
                }
            }
        }
    }
        /* And should check for invalid values for < 8bit types */
    else if (band->pixtype == PT_1BB ||
            band->pixtype == PT_2BUI ||
            band->pixtype == PT_4BUI) {
        {
            uint8_t maxVal = band->pixtype == PT_1BB ? 1 :
                    band->pixtype == PT_2BUI ? 3 :
                    15;
            uint8_t val;

            sz = width*height;
            for (v = 0; v < sz; ++v) {
                val = ((uint8_t*) band->data.mem)[v];
                if (val > maxVal) {
                    rterror("rt_band_from_wkb: Invalid value %d for pixel of type %s",
                            val, rt_pixtype_name(band->pixtype));
                    rtdealloc(band->data.mem);
                    rtdealloc(band);
                    return 0;
                }
            }
        }
    }

    /* And we should check if the band is a nodata band */
    /* TODO: No!! This is too slow */
    /*rt_band_check_is_nodata(band);*/

    return band;
}

/* -4 for size, +1 for endian */
#define RT_WKB_HDR_SZ (sizeof(struct rt_raster_serialized_t)-4+1)

rt_raster
rt_raster_from_wkb(const uint8_t* wkb, uint32_t wkbsize) {
    const uint8_t *ptr = wkb;
    const uint8_t *wkbend = NULL;
    rt_raster rast = NULL;
    uint8_t endian = 0;
    uint16_t version = 0;
    uint16_t i = 0;



    assert(NULL != ptr);

    /* Check that wkbsize is >= sizeof(rt_raster_serialized) */
    if (wkbsize < RT_WKB_HDR_SZ) {
        rterror("rt_raster_from_wkb: wkb size (%d)  < min size (%d)",
                wkbsize, RT_WKB_HDR_SZ);
        return 0;
    }
    wkbend = wkb + wkbsize;

    RASTER_DEBUGF(3, "Parsing header from wkb position %d (expected 0)",
            d_binptr_to_pos(ptr, wkbend, wkbsize));


    CHECK_BINPTR_POSITION(ptr, wkbend, wkbsize, 0);

    /* Read endianness */
    endian = *ptr;
    ptr += 1;

    /* Read version of protocol */
    version = read_uint16(&ptr, endian);
    if (version != 0) {
        rterror("rt_raster_from_wkb: WKB version %d unsupported", version);
        return 0;
    }

    /* Read other components of raster header */
    rast = (rt_raster) rtalloc(sizeof (struct rt_raster_t));
    if (!rast) {
        rterror("rt_raster_from_wkb: Out of memory allocating raster for wkb input");
        return 0;
    }
    rast->numBands = read_uint16(&ptr, endian);
    rast->scaleX = read_float64(&ptr, endian);
    rast->scaleY = read_float64(&ptr, endian);
    rast->ipX = read_float64(&ptr, endian);
    rast->ipY = read_float64(&ptr, endian);
    rast->skewX = read_float64(&ptr, endian);
    rast->skewY = read_float64(&ptr, endian);
		rt_raster_set_srid(rast, read_int32(&ptr, endian));
    rast->width = read_uint16(&ptr, endian);
    rast->height = read_uint16(&ptr, endian);

    /* Consistency checking, should have been checked before */
    assert(ptr <= wkbend);

    RASTER_DEBUGF(3, "rt_raster_from_wkb: Raster numBands: %d",
            rast->numBands);
    RASTER_DEBUGF(3, "rt_raster_from_wkb: Raster scale: %gx%g",
            rast->scaleX, rast->scaleY);
    RASTER_DEBUGF(3, "rt_raster_from_wkb: Raster ip: %gx%g",
            rast->ipX, rast->ipY);
    RASTER_DEBUGF(3, "rt_raster_from_wkb: Raster skew: %gx%g",
            rast->skewX, rast->skewY);
    RASTER_DEBUGF(3, "rt_raster_from_wkb: Raster srid: %d",
            rast->srid);
    RASTER_DEBUGF(3, "rt_raster_from_wkb: Raster dims: %dx%d",
            rast->width, rast->height);
    RASTER_DEBUGF(3, "Parsing raster header finished at wkb position %d (expected 61)",
            d_binptr_to_pos(ptr, wkbend, wkbsize));

    CHECK_BINPTR_POSITION(ptr, wkbend, wkbsize, 61);

    /* Read all bands of raster */

    if (!rast->numBands) {
        /* Here ptr should have been left to right after last used byte */
        if (ptr < wkbend) {
            rtwarn("%d bytes of WKB remained unparsed", wkbend - ptr);
        } else if (ptr > wkbend) {
            /* Easier to get a segfault before I guess */
            rtwarn("We parsed %d bytes more then available!", ptr - wkbend);
        }
        rast->bands = 0;
        return rast;
    }

    /* Now read the bands */
    rast->bands = (rt_band*) rtalloc(sizeof (rt_band) * rast->numBands);
    if (!rast->bands) {
        rterror("rt_raster_from_wkb: Out of memory allocating bands for WKB raster decoding");
        rtdealloc(rast);
        return 0;
    }

    /* ptr should now point to start of first band */
    assert(ptr <= wkbend); /* we should have checked this before */

    for (i = 0; i < rast->numBands; ++i) {
        RASTER_DEBUGF(3, "Parsing band %d from wkb position %d", i,
                d_binptr_to_pos(ptr, wkbend, wkbsize));

        rt_band band = rt_band_from_wkb(rast->width, rast->height,
                &ptr, wkbend, endian);
        if (!band) {
            rterror("rt_raster_from_wkb: Error reading WKB form of band %d", i);
            rtdealloc(rast);
            /* TODO: dealloc any previously allocated band too ! */
            return 0;
        }
				band->raster = rast;
        rast->bands[i] = band;
    }

    /* Here ptr should have been left to right after last used byte */
    if (ptr < wkbend) {
        rtwarn("%d bytes of WKB remained unparsed", wkbend - ptr);
    } else if (ptr > wkbend) {
        /* Easier to get a segfault before I guess */
        rtwarn("We parsed %d bytes more then available!",
                ptr - wkbend);
    }

    assert(NULL != rast);
    return rast;
}

rt_raster
rt_raster_from_hexwkb(const char* hexwkb,
        uint32_t hexwkbsize) {
    uint8_t* wkb = NULL;
    uint32_t wkbsize = 0;
    uint32_t i = 0;



    assert(NULL != hexwkb);

    RASTER_DEBUGF(3, "rt_raster_from_hexwkb: input wkb: %s", hexwkb);

    if (hexwkbsize % 2) {
        rterror("rt_raster_from_hexwkb: Raster HEXWKB input must have an even number of characters");
        return 0;
    }
    wkbsize = hexwkbsize / 2;

    wkb = rtalloc(wkbsize);
    if (!wkb) {
        rterror("rt_raster_from_hexwkb: Out of memory allocating memory for decoding HEXWKB");
        return 0;
    }

    for (i = 0; i < wkbsize; ++i) /* parse full hex */ {
        wkb[i] = parse_hex((char*) & (hexwkb[i * 2]));
    }

    rt_raster ret = rt_raster_from_wkb(wkb, wkbsize);

    rtdealloc(wkb); /* as long as rt_raster_from_wkb copies memory */

    return ret;
}

static uint32_t
rt_raster_wkb_size(rt_raster raster) {
    uint32_t size = RT_WKB_HDR_SZ;
    uint16_t i = 0;



    assert(NULL != raster);

    RASTER_DEBUGF(3, "rt_raster_wkb_size: computing size for %d bands",
            raster->numBands);

    for (i = 0; i < raster->numBands; ++i) {
        rt_band band = raster->bands[i];
        rt_pixtype pixtype = band->pixtype;
        int pixbytes = rt_pixtype_size(pixtype);

        RASTER_DEBUGF(3, "rt_raster_wkb_size: adding size of band %d", i);

        if (pixbytes < 1) {
            rterror("rt_raster_wkb_size: Corrupted band: unknown pixtype");
            return 0;
        }

        /* Add space for band type */
        size += 1;

        /* Add space for nodata value */
        size += pixbytes;

        if (band->offline) {
            /* Add space for band number */
            size += 1;

            /* Add space for null-terminated path */
            size += strlen(band->data.offline.path) + 1;
        } else {
            /* Add space for actual data */
            size += pixbytes * raster->width * raster->height;
        }

    }

    return size;
}

uint8_t *
rt_raster_to_wkb(rt_raster raster, uint32_t *wkbsize) {
#if POSTGIS_DEBUG_LEVEL > 0
    const uint8_t *wkbend = NULL;
#endif
    uint8_t *wkb = NULL;
    uint8_t *ptr = NULL;
    uint16_t i = 0;
    uint8_t littleEndian = isMachineLittleEndian();



    assert(NULL != raster);
    assert(NULL != wkbsize);

    RASTER_DEBUG(2, "rt_raster_to_wkb: about to call rt_raster_wkb_size");

    *wkbsize = rt_raster_wkb_size(raster);

    RASTER_DEBUGF(3, "rt_raster_to_wkb: found size: %d", *wkbsize);

    wkb = (uint8_t*) rtalloc(*wkbsize);
    if (!wkb) {
        rterror("rt_raster_to_wkb: Out of memory allocating WKB for raster");
        return 0;
    }

    ptr = wkb;

#if POSTGIS_DEBUG_LEVEL > 2
    wkbend = ptr + (*wkbsize);
#endif
    RASTER_DEBUGF(3, "Writing raster header to wkb on position %d (expected 0)",
            d_binptr_to_pos(ptr, wkbend, *wkbsize));

    /* Write endianness */
    *ptr = littleEndian;
    ptr += 1;

    /* Write version(size - (end - ptr)) */
    write_uint16(&ptr, littleEndian, 0);

    /* Copy header (from numBands up) */
    memcpy(ptr, &(raster->numBands), sizeof (struct rt_raster_serialized_t) - 6);
    ptr += sizeof (struct rt_raster_serialized_t) - 6;

    RASTER_DEBUGF(3, "Writing bands header to wkb position %d (expected 61)",
            d_binptr_to_pos(ptr, wkbend, *wkbsize));

    /* Serialize bands now */
    for (i = 0; i < raster->numBands; ++i) {
        rt_band band = raster->bands[i];
        rt_pixtype pixtype = band->pixtype;
        int pixbytes = rt_pixtype_size(pixtype);

        RASTER_DEBUGF(3, "Writing WKB for band %d", i);
        RASTER_DEBUGF(3, "Writing band pixel type to wkb position %d",
                d_binptr_to_pos(ptr, wkbend, *wkbsize));

        if (pixbytes < 1) {
            rterror("rt_raster_to_wkb: Corrupted band: unknown pixtype");
            return 0;
        }

        /* Add band type */
        *ptr = band->pixtype;
        if (band->offline) *ptr |= BANDTYPE_FLAG_OFFDB;
        if (band->hasnodata) *ptr |= BANDTYPE_FLAG_HASNODATA;
        if (band->isnodata) *ptr |= BANDTYPE_FLAG_ISNODATA;
        ptr += 1;

#if 0 /* no padding required for WKB */
        /* Add padding (if needed) */
        if (pixbytes > 1) {
            memset(ptr, '\0', pixbytes - 1);
            ptr += pixbytes - 1;
        }
        /* Consistency checking (ptr is pixbytes-aligned) */
        assert(!(((uint64_t) ptr) % pixbytes));
#endif

        RASTER_DEBUGF(3, "Writing band nodata to wkb position %d",
                d_binptr_to_pos(ptr, wkbend, *wkbsize));

        /* Add nodata value */
        switch (pixtype) {
            case PT_1BB:
            case PT_2BUI:
            case PT_4BUI:
            case PT_8BUI:
            {
                uint8_t v = band->nodataval;
                *ptr = v;
                ptr += 1;
                break;
            }
            case PT_8BSI:
            {
                int8_t v = band->nodataval;
                *ptr = v;
                ptr += 1;
                break;
            }
            case PT_16BSI:
            case PT_16BUI:
            {
                uint16_t v = band->nodataval;
                memcpy(ptr, &v, 2);
                ptr += 2;
                break;
            }
            case PT_32BSI:
            case PT_32BUI:
            {
                uint32_t v = band->nodataval;
                memcpy(ptr, &v, 4);
                ptr += 4;
                break;
            }
            case PT_32BF:
            {
                float v = band->nodataval;
                memcpy(ptr, &v, 4);
                ptr += 4;
                break;
            }
            case PT_64BF:
            {
                memcpy(ptr, &band->nodataval, 8);
                ptr += 8;
                break;
            }
            default:
                rterror("rt_raster_to_wkb: Fatal error caused by unknown pixel type. Aborting.");
                abort(); /* shoudn't happen */
                return 0;
        }

#if 0 /* no padding for WKB */
        /* Consistency checking (ptr is pixbytes-aligned) */
        assert(!((uint64_t) ptr % pixbytes));
#endif

        if (band->offline) {
            /* Write band number */
            *ptr = band->data.offline.bandNum;
            ptr += 1;

            /* Write path */
            strcpy((char*) ptr, band->data.offline.path);
            ptr += strlen(band->data.offline.path) + 1;
        } else {
            /* Write data */
            {
                uint32_t datasize = raster->width * raster->height * pixbytes;
                RASTER_DEBUGF(4, "rt_raster_to_wkb: Copying %d bytes", datasize);
                memcpy(ptr, band->data.mem, datasize);
                ptr += datasize;
            }
        }

#if 0 /* no padding for WKB */
        /* Pad up to 8-bytes boundary */
        while ((uint64_t) ptr % 8) {
            *ptr = 0;
            ++ptr;
        }

        /* Consistency checking (ptr is pixbytes-aligned) */
        assert(!((uint64_t) ptr % pixbytes));
#endif
    }

    return wkb;
}

char *
rt_raster_to_hexwkb(rt_raster raster, uint32_t *hexwkbsize) {
    uint8_t *wkb = NULL;
    char* hexwkb = NULL;
    uint32_t i = 0;
    uint32_t wkbsize = 0;



    assert(NULL != raster);
    assert(NULL != hexwkbsize);

    RASTER_DEBUG(2, "rt_raster_to_hexwkb: calling rt_raster_to_wkb");

    wkb = rt_raster_to_wkb(raster, &wkbsize);

    RASTER_DEBUG(3, "rt_raster_to_hexwkb: rt_raster_to_wkb returned");

    *hexwkbsize = wkbsize * 2; /* hex is 2 times bytes */
    hexwkb = (char*) rtalloc((*hexwkbsize) + 1);
    if (!hexwkb) {
        rtdealloc(wkb);
        rterror("rt_raster_to_hexwkb: Out of memory hexifying raster WKB");
        return 0;
    }
    hexwkb[*hexwkbsize] = '\0'; /* Null-terminate */

    for (i = 0; i < wkbsize; ++i) {
        deparse_hex(wkb[i], &(hexwkb[2 * i]));
    }

    rtdealloc(wkb); /* we don't need this anymore */

    RASTER_DEBUGF(3, "rt_raster_to_hexwkb: output wkb: %s", hexwkb);

    return hexwkb;
}

/*--------- Serializer/Deserializer --------------------------------------*/

static uint32_t
rt_raster_serialized_size(rt_raster raster) {
    uint32_t size = sizeof (struct rt_raster_serialized_t);
    uint16_t i = 0;



    assert(NULL != raster);

    RASTER_DEBUGF(3, "Serialized size with just header:%d - now adding size of %d bands",
            size, raster->numBands);

    for (i = 0; i < raster->numBands; ++i) {
        rt_band band = raster->bands[i];
        rt_pixtype pixtype = band->pixtype;
        int pixbytes = rt_pixtype_size(pixtype);

        if (pixbytes < 1) {
            rterror("rt_raster_serialized_size: Corrupted band: unknown pixtype");
            return 0;
        }

        /* Add space for band type, hasnodata flag and data padding */
        size += pixbytes;

        /* Add space for nodata value */
        size += pixbytes;

        if (band->offline) {
            /* Add space for band number */
            size += 1;

            /* Add space for null-terminated path */
            size += strlen(band->data.offline.path) + 1;
        } else {
            /* Add space for raster band data */
            size += pixbytes * raster->width * raster->height;
        }

        RASTER_DEBUGF(3, "Size before alignment is %d", size);

        /* Align size to 8-bytes boundary (trailing padding) */
        /* XXX jorgearevalo: bug here. If the size is actually 8-bytes aligned,
         this line will add 8 bytes trailing padding, and it's not necessary */
        /*size += 8 - (size % 8);*/
        if (size % 8)
            size += 8 - (size % 8);

        RASTER_DEBUGF(3, "Size after alignment is %d", size);
    }

    return size;
}

void*
rt_raster_serialize(rt_raster raster) {
    uint32_t size = rt_raster_serialized_size(raster);
    uint8_t* ret = NULL;
    uint8_t* ptr = NULL;
    uint16_t i = 0;


    assert(NULL != raster);

    ret = (uint8_t*) rtalloc(size);
    if (!ret) {
        rterror("rt_raster_serialize: Out of memory allocating %d bytes for serializing a raster",
                size);
        return 0;
    }
    memset(ret, '-', size);

    ptr = ret;

    RASTER_DEBUGF(3, "sizeof(struct rt_raster_serialized_t):%u",
            sizeof (struct rt_raster_serialized_t));
    RASTER_DEBUGF(3, "sizeof(struct rt_raster_t):%u",
            sizeof (struct rt_raster_t));
    RASTER_DEBUGF(3, "serialized size:%lu", (long unsigned) size);

    /* Set size */
    /* NOTE: Value of rt_raster.size may be updated in
     * returned object, for instance, by rt_pg layer to
     * store value calculated by SET_VARSIZE.
     */
    raster->size = size;

    /* Set version */
    raster->version = 0;

    /* Copy header */
    memcpy(ptr, raster, sizeof (struct rt_raster_serialized_t));

    RASTER_DEBUG(3, "Start hex dump of raster being serialized using 0x2D to mark non-written bytes");

#if POSTGIS_DEBUG_LEVEL > 2
    uint8_t* dbg_ptr = ptr;
    d_print_binary_hex("HEADER", dbg_ptr, size);
#endif

    ptr += sizeof (struct rt_raster_serialized_t);

    /* Serialize bands now */
    for (i = 0; i < raster->numBands; ++i) {
        rt_band band = raster->bands[i];
        assert(NULL != band);

        rt_pixtype pixtype = band->pixtype;
        int pixbytes = rt_pixtype_size(pixtype);
        if (pixbytes < 1) {
            rterror("rt_raster_serialize: Corrupted band: unknown pixtype");
            return 0;
        }

        /* Add band type */
        *ptr = band->pixtype;
        if (band->offline) {
            *ptr |= BANDTYPE_FLAG_OFFDB;
        }
        if (band->hasnodata) {
            *ptr |= BANDTYPE_FLAG_HASNODATA;
        }

        if (band->isnodata) {
            *ptr |= BANDTYPE_FLAG_ISNODATA;
        }

#if POSTGIS_DEBUG_LEVEL > 2
        d_print_binary_hex("PIXTYPE", dbg_ptr, size);
#endif

        ptr += 1;

        /* Add padding (if needed) */
        if (pixbytes > 1) {
            memset(ptr, '\0', pixbytes - 1);
            ptr += pixbytes - 1;
        }

#if POSTGIS_DEBUG_LEVEL > 2
        d_print_binary_hex("PADDING", dbg_ptr, size);
#endif

        /* Consistency checking (ptr is pixbytes-aligned) */
        assert(!((ptr - ret) % pixbytes));

        /* Add nodata value */
        switch (pixtype) {
            case PT_1BB:
            case PT_2BUI:
            case PT_4BUI:
            case PT_8BUI:
            {
                uint8_t v = band->nodataval;
                *ptr = v;
                ptr += 1;
                break;
            }
            case PT_8BSI:
            {
                int8_t v = band->nodataval;
                *ptr = v;
                ptr += 1;
                break;
            }
            case PT_16BSI:
            case PT_16BUI:
            {
                uint16_t v = band->nodataval;
                memcpy(ptr, &v, 2);
                ptr += 2;
                break;
            }
            case PT_32BSI:
            case PT_32BUI:
            {
                uint32_t v = band->nodataval;
                memcpy(ptr, &v, 4);
                ptr += 4;
                break;
            }
            case PT_32BF:
            {
                float v = band->nodataval;
                memcpy(ptr, &v, 4);
                ptr += 4;
                break;
            }
            case PT_64BF:
            {
                memcpy(ptr, &band->nodataval, 8);
                ptr += 8;
                break;
            }
            default:
                rterror("rt_raster_serialize: Fatal error caused by unknown pixel type. Aborting.");
                abort(); /* shouldn't happen */
                return 0;
        }

        /* Consistency checking (ptr is pixbytes-aligned) */
        assert(!((ptr - ret) % pixbytes));

#if POSTGIS_DEBUG_LEVEL > 2
        d_print_binary_hex("nodata", dbg_ptr, size);
#endif

        if (band->offline) {
            /* Write band number */
            *ptr = band->data.offline.bandNum;
            ptr += 1;

            /* Write path */
            strcpy((char*) ptr, band->data.offline.path);
            ptr += strlen(band->data.offline.path) + 1;
        } else {
            /* Write data */
            uint32_t datasize = raster->width * raster->height * pixbytes;
            memcpy(ptr, band->data.mem, datasize);
            ptr += datasize;
        }

#if POSTGIS_DEBUG_LEVEL > 2
        d_print_binary_hex("BAND", dbg_ptr, size);
#endif

        /* Pad up to 8-bytes boundary */
        while ((uintptr_t) ptr % 8) {
            *ptr = 0;
            ++ptr;

            RASTER_DEBUGF(3, "PAD at %d", (uintptr_t) ptr % 8);

        }

        /* Consistency checking (ptr is pixbytes-aligned) */
        assert(!((ptr - ret) % pixbytes));

    } /* for-loop over bands */

#if POSTGIS_DEBUG_LEVEL > 2
    d_print_binary_hex("SERIALIZED RASTER", dbg_ptr, size);
#endif

    return ret;
}

rt_raster
rt_raster_deserialize(void* serialized, int header_only) {
    rt_raster rast = NULL;
    const uint8_t *ptr = NULL;
    const uint8_t *beg = NULL;
    uint16_t i = 0;
    uint8_t littleEndian = isMachineLittleEndian();



    assert(NULL != serialized);

    RASTER_DEBUG(2, "rt_raster_deserialize: Entering...");

    /* NOTE: Value of rt_raster.size may be different
     * than actual size of raster data being read.
     * See note on SET_VARSIZE in rt_raster_serialize function above.
     */

    /* Allocate memory for deserialized raster header */

    RASTER_DEBUG(3, "rt_raster_deserialize: Allocating memory for deserialized raster header");
    rast = (rt_raster) rtalloc(sizeof (struct rt_raster_t));
    if (!rast) {
        rterror("rt_raster_deserialize: Out of memory allocating raster for deserialization");
        return 0;
    }

    /* Deserialize raster header */
    RASTER_DEBUG(3, "rt_raster_deserialize: Deserialize raster header");
    memcpy(rast, serialized, sizeof (struct rt_raster_serialized_t));

    if (0 == rast->numBands || header_only) {
        rast->bands = 0;
        return rast;
    }
    beg = (const uint8_t*) serialized;

    RASTER_DEBUG(3, "rt_raster_deserialize: Allocating memory for bands");
    /* Allocate registry of raster bands */
    rast->bands = rtalloc(rast->numBands * sizeof (rt_band));

    RASTER_DEBUGF(3, "rt_raster_deserialize: %d bands", rast->numBands);

    /* Move to the beginning of first band */
    ptr = beg;
    ptr += sizeof (struct rt_raster_serialized_t);

    /* Deserialize bands now */
    for (i = 0; i < rast->numBands; ++i) {
        rt_band band = NULL;
        uint8_t type = 0;
        int pixbytes = 0;

        band = rtalloc(sizeof (struct rt_band_t));
        if (!band) {
            rterror("rt_raster_deserialize: Out of memory allocating rt_band during deserialization");
            return 0;
        }

        rast->bands[i] = band;

        type = *ptr;
        ptr++;
        band->pixtype = type & BANDTYPE_PIXTYPE_MASK;

        RASTER_DEBUGF(3, "rt_raster_deserialize: band %d with pixel type %s", i, rt_pixtype_name(band->pixtype));

        band->offline = BANDTYPE_IS_OFFDB(type) ? 1 : 0;
        band->hasnodata = BANDTYPE_HAS_NODATA(type) ? 1 : 0;
        band->isnodata = BANDTYPE_IS_NODATA(type) ? 1 : 0;
        band->width = rast->width;
        band->height = rast->height;
        band->ownsData = 0;
				band->raster = rast;

        /* Advance by data padding */
        pixbytes = rt_pixtype_size(band->pixtype);
        ptr += pixbytes - 1;

        /* Read nodata value */
        switch (band->pixtype) {
            case PT_1BB:
            {
                band->nodataval = ((int) read_uint8(&ptr)) & 0x01;
                break;
            }
            case PT_2BUI:
            {
                band->nodataval = ((int) read_uint8(&ptr)) & 0x03;
                break;
            }
            case PT_4BUI:
            {
                band->nodataval = ((int) read_uint8(&ptr)) & 0x0F;
                break;
            }
            case PT_8BSI:
            {
                band->nodataval = read_int8(&ptr);
                break;
            }
            case PT_8BUI:
            {
                band->nodataval = read_uint8(&ptr);
                break;
            }
            case PT_16BSI:
            {
                band->nodataval = read_int16(&ptr, littleEndian);
                break;
            }
            case PT_16BUI:
            {
                band->nodataval = read_uint16(&ptr, littleEndian);
                break;
            }
            case PT_32BSI:
            {
                band->nodataval = read_int32(&ptr, littleEndian);
                break;
            }
            case PT_32BUI:
            {
                band->nodataval = read_uint32(&ptr, littleEndian);
                break;
            }
            case PT_32BF:
            {
                band->nodataval = read_float32(&ptr, littleEndian);
                break;
            }
            case PT_64BF:
            {
                band->nodataval = read_float64(&ptr, littleEndian);
                break;
            }
            default:
            {
                rterror("rt_raster_deserialize: Unknown pixeltype %d", band->pixtype);
                rtdealloc(band);
                rtdealloc(rast);
                return 0;
            }
        }

        RASTER_DEBUGF(3, "rt_raster_deserialize: has nodata flag %d", band->hasnodata);
        RASTER_DEBUGF(3, "rt_raster_deserialize: nodata value %g", band->nodataval);

        /* Consistency checking (ptr is pixbytes-aligned) */
        assert(!((ptr - beg) % pixbytes));

        if (band->offline) {
            /* Read band number */
            band->data.offline.bandNum = *ptr;
            ptr += 1;

            /* Register path */
            band->data.offline.path = (char*) ptr;
            ptr += strlen(band->data.offline.path) + 1;

						band->data.offline.mem = NULL;
        } else {
            /* Register data */
            const uint32_t datasize = rast->width * rast->height * pixbytes;
            band->data.mem = (uint8_t*) ptr;
            ptr += datasize;
        }

        /* Skip bytes of padding up to 8-bytes boundary */
#if POSTGIS_DEBUG_LEVEL > 0
        const uint8_t *padbeg = ptr;
#endif
        while (0 != ((ptr - beg) % 8)){
            ++ptr;
        }

        RASTER_DEBUGF(3, "rt_raster_deserialize: skip %d bytes of 8-bytes boundary padding", ptr - padbeg);

        /* Consistency checking (ptr is pixbytes-aligned) */
        assert(!((ptr - beg) % pixbytes));
    }

    return rast;
}

/**
 * Return TRUE if the raster is empty. i.e. is NULL, width = 0 or height = 0
 *
 * @param raster: the raster to get info from
 *
 * @return TRUE if the raster is empty, FALSE otherwise
 */
int
rt_raster_is_empty(rt_raster raster) {
	return (NULL == raster || raster->height <= 0 || raster->width <= 0);
}

/**
 * Return TRUE if the raster do not have a band of this number.
 *
 * @param raster: the raster to get info from
 * @param nband: the band number. 0-based
 *
 * @return TRUE if the raster do not have a band of this number, FALSE otherwise
 */
int
rt_raster_has_no_band(rt_raster raster, int nband) {
	return (NULL == raster || nband >= raster->numBands || nband < 0);
}

/**
 * Copy one band from one raster to another.  Bands are duplicated from
 * fromrast to torast using rt_band_duplicate.  The caller will need
 * to ensure that the copied band's data or path remains allocated
 * for the lifetime of the copied bands.
 *
 * @param torast: raster to copy band to
 * @param fromrast: raster to copy band from
 * @param fromindex: index of band in source raster, 0-based
 * @param toindex: index of new band in destination raster, 0-based
 *
 * @return The band index of the second raster where the new band is copied.
 */
int32_t
rt_raster_copy_band(
	rt_raster torast, rt_raster fromrast,
	int fromindex, int toindex
) {
	rt_band srcband = NULL;
	rt_band dstband = NULL;

	assert(NULL != torast);
	assert(NULL != fromrast);

	/* Check raster dimensions */
	if (torast->height != fromrast->height || torast->width != fromrast->width) {
		rtwarn("rt_raster_copy_band: Attempting to add a band with different width or height");
		return -1;
	}

	/* Check bands limits */
	if (fromrast->numBands < 1) {
		rtwarn("rt_raster_copy_band: Second raster has no band");
		return -1;
	}
	else if (fromindex < 0) {
		rtwarn("rt_raster_copy_band: Band index for second raster < 0. Defaulted to 0");
		fromindex = 0;
	}
	else if (fromindex >= fromrast->numBands) {
		rtwarn("rt_raster_copy_band: Band index for second raster > number of bands, truncated from %u to %u", fromindex, fromrast->numBands - 1);
		fromindex = fromrast->numBands - 1;
	}

	if (toindex < 0) {
		rtwarn("rt_raster_copy_band: Band index for first raster < 0. Defaulted to 0");
		toindex = 0;
	}
	else if (toindex > torast->numBands) {
		rtwarn("rt_raster_copy_band: Band index for first raster > number of bands, truncated from %u to %u", toindex, torast->numBands);
		toindex = torast->numBands;
	}

	/* Get band from source raster */
	srcband = rt_raster_get_band(fromrast, fromindex);

	/* duplicate band */
	dstband = rt_band_duplicate(srcband);

	/* Add band to the second raster */
	return rt_raster_add_band(torast, dstband, toindex);
}

/**
 * Construct a new rt_raster from an existing rt_raster and an array
 * of band numbers
 *
 * @param raster : the source raster
 * @param bandNums : array of band numbers to extract from source raster
 *                   and add to the new raster (0 based)
 * @param count : number of elements in bandNums
 *
 * @return a new rt_raster or 0 on error
 */
rt_raster
rt_raster_from_band(rt_raster raster, uint32_t *bandNums, int count) {
	rt_raster rast = NULL;
	int i = 0;
	int idx;
	int32_t flag;
	double gt[6] = {0.};

	assert(NULL != raster);
	assert(NULL != bandNums);

	RASTER_DEBUGF(3, "rt_raster_from_band: source raster has %d bands",
		rt_raster_get_num_bands(raster));

	/* create new raster */
	rast = rt_raster_new(raster->width, raster->height);
	if (NULL == rast) {
		rterror("rt_raster_from_band: Out of memory allocating new raster");
		return 0;
	}

	/* copy raster attributes */
	rt_raster_get_geotransform_matrix(raster, gt);
	rt_raster_set_geotransform_matrix(rast, gt);

	/* srid */
	rt_raster_set_srid(rast, raster->srid);

	/* copy bands */
	for (i = 0; i < count; i++) {
		idx = bandNums[i];
		flag = rt_raster_copy_band(rast, raster, idx, i);

		if (flag < 0) {
			rterror("rt_raster_from_band: Unable to copy band");
			rt_raster_destroy(rast);
			return NULL;
		}

		RASTER_DEBUGF(3, "rt_raster_from_band: band created at index %d",
			flag);
	}

	RASTER_DEBUGF(3, "rt_raster_from_band: new raster has %d bands",
		rt_raster_get_num_bands(rast));
	return rast;
}

/**
 * Replace band at provided index with new band
 *
 * @param raster: raster of band to be replaced
 * @param band : new band to add to raster
 * @param index : index of band to replace (0-based)
 *
 * @return 0 on error or replaced band
 */
rt_band
rt_raster_replace_band(rt_raster raster, rt_band band, int index) {
	rt_band oldband = NULL;
	assert(NULL != raster);

	if (band->width != raster->width || band->height != raster->height) {
		rterror("rt_raster_replace_band: Band does not match raster's dimensions: %dx%d band to %dx%d raster",
			band->width, band->height, raster->width, raster->height);
		return 0;
	}

	if (index >= raster->numBands || index < 0) {
		rterror("rt_raster_replace_band: Band index is not valid");
		return 0;
	}

	oldband = rt_raster_get_band(raster, index);
	RASTER_DEBUGF(3, "rt_raster_replace_band: old band at %p", oldband);
	RASTER_DEBUGF(3, "rt_raster_replace_band: new band at %p", band);

	raster->bands[index] = band;
	RASTER_DEBUGF(3, "rt_raster_replace_band: new band at %p", raster->bands[index]);

	band->raster = raster;

	return oldband;
}

/**
 * Return formatted GDAL raster from raster
 *
 * @param raster : the raster to convert
 * @param srs : the raster's coordinate system in OGC WKT
 * @param format : format to convert to. GDAL driver short name
 * @param options : list of format creation options. array of strings
 * @param gdalsize : will be set to the size of returned bytea
 *
 * @return formatted GDAL raster.  the calling function is responsible
 *   for freeing the returned data using CPLFree()
 */
uint8_t*
rt_raster_to_gdal(rt_raster raster, const char *srs,
	char *format, char **options, uint64_t *gdalsize) {
	GDALDriverH src_drv = NULL;
	GDALDatasetH src_ds = NULL;

	vsi_l_offset rtn_lenvsi;
	uint64_t rtn_len = 0;

	GDALDriverH rtn_drv = NULL;
	GDALDatasetH rtn_ds = NULL;
	uint8_t *rtn = NULL;

	assert(NULL != raster);

	/* any supported format is possible */
	GDALAllRegister();
	RASTER_DEBUG(3, "rt_raster_to_gdal: loaded all supported GDAL formats");

	/* output format not specified */
	if (format == NULL || !strlen(format))
		format = "GTiff";
	RASTER_DEBUGF(3, "rt_raster_to_gdal: output format is %s", format);

	/* load raster into a GDAL MEM raster */
	src_ds = rt_raster_to_gdal_mem(raster, srs, NULL, 0, &src_drv);
	if (NULL == src_ds) {
		rterror("rt_raster_to_gdal: Unable to convert raster to GDAL MEM format");
		return 0;
	}

	/* load driver */
	rtn_drv = GDALGetDriverByName(format);
	if (NULL == rtn_drv) {
		rterror("rt_raster_to_gdal: Unable to load the output GDAL driver");
		GDALClose(src_ds);
		return 0;
	}
	RASTER_DEBUG(3, "rt_raster_to_gdal: Output driver loaded");

	/* convert GDAL MEM raster to output format */
	RASTER_DEBUG(3, "rt_raster_to_gdal: Copying GDAL MEM raster to memory file in output format");
	rtn_ds = GDALCreateCopy(
		rtn_drv,
		"/vsimem/out.dat", /* should be fine assuming this is in a process */
		src_ds,
		FALSE, /* should copy be strictly equivelent? */
		options, /* format options */
		NULL, /* progress function */
		NULL /* progress data */
	);
	if (NULL == rtn_ds) {
		rterror("rt_raster_to_gdal: Unable to create the output GDAL dataset");
		GDALClose(src_ds);
		return 0;
	}

	/* close source dataset */
	GDALClose(src_ds);
	RASTER_DEBUG(3, "rt_raster_to_gdal: Closed GDAL MEM raster");

	/* close dataset, this also flushes any pending writes */
	GDALClose(rtn_ds);
	RASTER_DEBUG(3, "rt_raster_to_gdal: Closed GDAL output raster");

	RASTER_DEBUG(3, "rt_raster_to_gdal: Done copying GDAL MEM raster to memory file in output format");

	/* from memory file to buffer */
	RASTER_DEBUG(3, "rt_raster_to_gdal: Copying GDAL memory file to buffer");
	rtn = VSIGetMemFileBuffer("/vsimem/out.dat", &rtn_lenvsi, TRUE);
	RASTER_DEBUG(3, "rt_raster_to_gdal: Done copying GDAL memory file to buffer");
	if (NULL == rtn) {
		rterror("rt_raster_to_gdal: Unable to create the output GDAL raster");
		return 0;
	}

	rtn_len = (uint64_t) rtn_lenvsi;
	*gdalsize = rtn_len;

	return rtn;
}

/**
 * Returns a set of available GDAL drivers
 *
 * @param drv_count : number of GDAL drivers available
 * @param cancc : if non-zero, filter drivers to only those
 *   with support for CreateCopy and VirtualIO
 *
 * @return set of "gdaldriver" values of available GDAL drivers
 */
rt_gdaldriver
rt_raster_gdal_drivers(uint32_t *drv_count, uint8_t cancc) {
	const char *state;
	const char *txt;
	int txt_len;
	GDALDriverH *drv = NULL;
	rt_gdaldriver rtn = NULL;
	int count;
	int i;
	uint32_t j;

	GDALAllRegister();
	count = GDALGetDriverCount();
	rtn = (rt_gdaldriver) rtalloc(count * sizeof(struct rt_gdaldriver_t));
	if (NULL == rtn) {
		rterror("rt_raster_gdal_drivers: Unable to allocate memory for gdaldriver structure");
		return 0;
	}

	for (i = 0, j = 0; i < count; i++) {
		drv = GDALGetDriver(i);

		if (cancc) {
			/* CreateCopy support */
			state = GDALGetMetadataItem(drv, GDAL_DCAP_CREATECOPY, NULL);
			if (state == NULL) continue;

			/* VirtualIO support */
			state = GDALGetMetadataItem(drv, GDAL_DCAP_VIRTUALIO, NULL);
			if (state == NULL) continue;
		}

		/* index of driver */
		rtn[j].idx = i;

		/* short name */
		txt = GDALGetDriverShortName(drv);
		txt_len = strlen(txt);

		if (cancc) {
			RASTER_DEBUGF(3, "rt_raster_gdal_driver: driver %s (%d) supports CreateCopy() and VirtualIO()", txt, i);
		}

		txt_len = (txt_len + 1) * sizeof(char);
		rtn[j].short_name = (char *) rtalloc(txt_len);
		memcpy(rtn[j].short_name, txt, txt_len);

		/* long name */
		txt = GDALGetDriverLongName(drv);
		txt_len = strlen(txt);

		txt_len = (txt_len + 1) * sizeof(char);
		rtn[j].long_name = (char *) rtalloc(txt_len);
		memcpy(rtn[j].long_name, txt, txt_len);

		/* creation options */
		txt = GDALGetDriverCreationOptionList(drv);
		txt_len = strlen(txt);

		txt_len = (txt_len + 1) * sizeof(char);
		rtn[j].create_options = (char *) rtalloc(txt_len);
		memcpy(rtn[j].create_options, txt, txt_len);

		j++;
	}

	/* free unused memory */
	rtn = rtrealloc(rtn, j * sizeof(struct rt_gdaldriver_t));
	*drv_count = j;

	return rtn;
}

/**
 * Return GDAL dataset using GDAL MEM driver from raster
 *
 * @param raster : raster to convert to GDAL MEM
 * @param srs : the raster's coordinate system in OGC WKT
 * @param bandNums : array of band numbers to extract from raster
 *                   and include in the GDAL dataset (0 based)
 * @param count : number of elements in bandNums
 * @param rtn_drv : is set to the GDAL driver object
 *
 * @return GDAL dataset using GDAL MEM driver
 */
GDALDatasetH
rt_raster_to_gdal_mem(rt_raster raster, const char *srs,
	uint32_t *bandNums, int count, GDALDriverH *rtn_drv) {
	GDALDriverH drv = NULL;
	GDALDatasetH ds = NULL;
	double gt[6] = {0.0};
	CPLErr cplerr;
	GDALDataType gdal_pt = GDT_Unknown;
	GDALRasterBandH band;
	void *pVoid;
	char *pszDataPointer;
	char szGDALOption[50];
	char *apszOptions[4];
	double nodata = 0.0;
	int allocBandNums = 0;

	int i;
	int numBands;
	uint32_t width = 0;
	uint32_t height = 0;
	rt_band rtband = NULL;
	rt_pixtype pt = PT_END;

	assert(NULL != raster);

	/* store raster in GDAL MEM raster */
	if (!rt_util_gdal_driver_registered("MEM"))
		GDALRegister_MEM();
	drv = GDALGetDriverByName("MEM");
	if (NULL == drv) {
		rterror("rt_raster_to_gdal_mem: Unable to load the MEM GDAL driver");
		return 0;
	}
	*rtn_drv = drv;

	width = rt_raster_get_width(raster);
	height = rt_raster_get_height(raster);
	ds = GDALCreate(
		drv, "",
		width, height,
		0, GDT_Byte, NULL
	);
	if (NULL == ds) {
		rterror("rt_raster_to_gdal_mem: Could not create a GDALDataset to convert into");
		return 0;
	}

	/* add geotransform */
	rt_raster_get_geotransform_matrix(raster, gt);
	cplerr = GDALSetGeoTransform(ds, gt);
	if (cplerr != CE_None) {
		rterror("rt_raster_to_gdal_mem: Unable to set geotransformation");
		GDALClose(ds);
		return 0;
	}

	/* set spatial reference */
	if (NULL != srs && strlen(srs)) {
		cplerr = GDALSetProjection(ds, srs);
		if (cplerr != CE_None) {
			rterror("rt_raster_to_gdal_mem: Unable to set projection");
			GDALClose(ds);
			return 0;
		}
		RASTER_DEBUGF(3, "Projection set to: %s", srs);
	}

	/* process bandNums */
	numBands = rt_raster_get_num_bands(raster);
	if (NULL != bandNums && count > 0) {
		for (i = 0; i < count; i++) {
			if (bandNums[i] < 0 || bandNums[i] >= numBands) {
				rterror("rt_raster_to_gdal_mem: The band index %d is invalid", bandNums[i]);
				GDALClose(ds);
				return 0;
			}
		}
	}
	else {
		count = numBands;
		bandNums = (uint32_t *) rtalloc(sizeof(uint32_t) * count);
		if (NULL == bandNums) {
			rterror("rt_raster_to_gdal_mem: Unable to allocate memory for band indices");
			GDALClose(ds);
			return 0;
		}
		allocBandNums = 1;
		for (i = 0; i < count; i++) bandNums[i] = i;
	}

	/* add band(s) */
	for (i = 0; i < count; i++) {
		rtband = rt_raster_get_band(raster, bandNums[i]);
		if (NULL == rtband) {
			rterror("rt_raster_to_gdal_mem: Unable to get requested band index %d", bandNums[i]);
			if (allocBandNums) rtdealloc(bandNums);
			GDALClose(ds);
			return 0;
		}

		pt = rt_band_get_pixtype(rtband);
		gdal_pt = rt_util_pixtype_to_gdal_datatype(pt);
		if (gdal_pt == GDT_Unknown)
			rtwarn("rt_raster_to_gdal_mem: Unknown pixel type for band");

		/*
			For all pixel types other than PT_8BSI, set pointer to start of data
		*/
		if (pt != PT_8BSI) {
			pVoid = rt_band_get_data(rtband);
			RASTER_DEBUGF(4, "Band data is at pos %p", pVoid);

			pszDataPointer = (char *) rtalloc(20 * sizeof (char));
			sprintf(pszDataPointer, "%p", pVoid);
			RASTER_DEBUGF(4, "rt_raster_to_gdal_mem: szDatapointer is %p",
				pszDataPointer);

			if (strnicmp(pszDataPointer, "0x", 2) == 0)
				sprintf(szGDALOption, "DATAPOINTER=%s", pszDataPointer);
			else
				sprintf(szGDALOption, "DATAPOINTER=0x%s", pszDataPointer);

			RASTER_DEBUG(3, "Storing info for GDAL MEM raster band");

			apszOptions[0] = szGDALOption;
			apszOptions[1] = NULL; /* pixel offset, not needed */
			apszOptions[2] = NULL; /* line offset, not needed */
			apszOptions[3] = NULL;

			/* free */
			rtdealloc(pszDataPointer);

			/* add band */
			if (GDALAddBand(ds, gdal_pt, apszOptions) == CE_Failure) {
				rterror("rt_raster_to_gdal_mem: Could not add GDAL raster band");
				if (allocBandNums) rtdealloc(bandNums);
				GDALClose(ds);
				return 0;
			}
		}
		/*
			PT_8BSI is special as GDAL has no equivalent pixel type.
			Must convert 8BSI to 16BSI so create basic band
		*/
		else {
			/* add band */
			if (GDALAddBand(ds, gdal_pt, NULL) == CE_Failure) {
				rterror("rt_raster_to_gdal_mem: Could not add GDAL raster band");
				if (allocBandNums) rtdealloc(bandNums);
				GDALClose(ds);
				return 0;
			}
		}

		/* check band count */
		if (GDALGetRasterCount(ds) != i + 1) {
			rterror("rt_raster_to_gdal_mem: Error creating GDAL MEM raster band");
			if (allocBandNums) rtdealloc(bandNums);
			GDALClose(ds);
			return 0;
		}

		/* get new band */
		band = NULL;
		band = GDALGetRasterBand(ds, i + 1);
		if (NULL == band) {
			rterror("rt_raster_to_gdal_mem: Could not get GDAL band for additional processing");
			if (allocBandNums) rtdealloc(bandNums);
			GDALClose(ds);
			return 0;
		}

		/* PT_8BSI requires manual setting of pixels */
		if (pt == PT_8BSI) {
			int nXBlocks, nYBlocks;
			int nXBlockSize, nYBlockSize;
			int iXBlock, iYBlock;
			int nXValid, nYValid;
			int iX, iY;
			int iXMax, iYMax;

			int x, y, z;
			uint32_t valueslen = 0;
			int16_t *values = NULL;
			double value = 0.;

			/* this makes use of GDAL's "natural" blocks */
			GDALGetBlockSize(band, &nXBlockSize, &nYBlockSize);
			nXBlocks = (width + nXBlockSize - 1) / nXBlockSize;
			nYBlocks = (height + nYBlockSize - 1) / nYBlockSize;
			RASTER_DEBUGF(4, "(nXBlockSize, nYBlockSize) = (%d, %d)", nXBlockSize, nYBlockSize);
			RASTER_DEBUGF(4, "(nXBlocks, nYBlocks) = (%d, %d)", nXBlocks, nYBlocks);

			/* length is for the desired pixel type */
			valueslen = rt_pixtype_size(PT_16BSI) * nXBlockSize * nYBlockSize;
			values = rtalloc(valueslen);
			if (NULL == values) {
				rterror("rt_raster_to_gdal_mem: Could not allocate memory for GDAL band pixel values");
				if (allocBandNums) rtdealloc(bandNums);
				GDALClose(ds);
				return 0;
			}

			for (iYBlock = 0; iYBlock < nYBlocks; iYBlock++) {
				for (iXBlock = 0; iXBlock < nXBlocks; iXBlock++) {
					memset(values, 0, valueslen);

					x = iXBlock * nXBlockSize;
					y = iYBlock * nYBlockSize;
					RASTER_DEBUGF(4, "(iXBlock, iYBlock) = (%d, %d)", iXBlock, iYBlock);
					RASTER_DEBUGF(4, "(x, y) = (%d, %d)", x, y);

					/* valid block width */
					if ((iXBlock + 1) * nXBlockSize > width)
						nXValid = width - (iXBlock * nXBlockSize);
					else
						nXValid = nXBlockSize;

					/* valid block height */
					if ((iYBlock + 1) * nYBlockSize > height)
						nYValid = height - (iYBlock * nYBlockSize);
					else
						nYValid = nYBlockSize;

					RASTER_DEBUGF(4, "(nXValid, nYValid) = (%d, %d)", nXValid, nYValid);

					/* convert 8BSI values to 16BSI */
					z = 0;
					iYMax = y + nYValid;
					iXMax = x + nXValid;
					for (iY = y; iY < iYMax; iY++)  {
						for (iX = x; iX < iXMax; iX++)  {
							if (rt_band_get_pixel(rtband, iX, iY, &value) != 0) {
								rterror("rt_raster_to_gdal_mem: Could not get pixel value to convert from 8BSI to 16BSI");
								rtdealloc(values);
								if (allocBandNums) rtdealloc(bandNums);
								GDALClose(ds);
								return 0;
							}

							values[z++] = rt_util_clamp_to_16BSI(value);
						}
					}

					/* burn values */
					if (GDALRasterIO(
						band, GF_Write,
						x, y,
						nXValid, nYValid,
						values, nXValid, nYValid,
						gdal_pt,
						0, 0
					) != CE_None) {
						rterror("rt_raster_to_gdal_mem: Could not write converted 8BSI to 16BSI values to GDAL band");
						rtdealloc(values);
						if (allocBandNums) rtdealloc(bandNums);
						GDALClose(ds);
						return 0;
					}
				}
			}

			rtdealloc(values);
		}

		/* Add nodata value for band */
		if (rt_band_get_hasnodata_flag(rtband) != FALSE) {
			nodata = rt_band_get_nodata(rtband);
			if (GDALSetRasterNoDataValue(band, nodata) != CE_None)
				rtwarn("rt_raster_to_gdal_mem: Could not set nodata value for band");
			RASTER_DEBUGF(3, "nodata value set to %f", GDALGetRasterNoDataValue(band, NULL));
		}
	}

	/* necessary??? */
	GDALFlushCache(ds);

	if (allocBandNums) rtdealloc(bandNums);

	return ds;
}

/**
 * Return a raster from a GDAL dataset
 *
 * @param ds : the GDAL dataset to convert to a raster
 *
 * @return raster
 */
rt_raster
rt_raster_from_gdal_dataset(GDALDatasetH ds) {
	rt_raster rast = NULL;
	double gt[6] = {0};
	CPLErr cplerr;
	uint32_t width = 0;
	uint32_t height = 0;
	uint32_t numBands = 0;
	int i = 0;
	int status;

	const char *srs = NULL;

	GDALRasterBandH gdband = NULL;
	GDALDataType gdpixtype = GDT_Unknown;
	rt_band band;
	int32_t idx;
	rt_pixtype pt = PT_END;
	uint32_t ptlen = 0;
	uint32_t hasnodata = 0;
	double nodataval;

	int x;
	int y;

	int nXBlocks, nYBlocks;
	int nXBlockSize, nYBlockSize;
	int iXBlock, iYBlock;
	int nXValid, nYValid;
	int iY;

	void *values = NULL;
	uint32_t valueslen = 0;
	void *ptr = NULL;

	assert(NULL != ds);

	/* raster size */
	width = GDALGetRasterXSize(ds);
	height = GDALGetRasterYSize(ds);
	RASTER_DEBUGF(3, "Raster dimensions (width x height): %d x %d", width, height);

	/* create new raster */
	RASTER_DEBUG(3, "Creating new raster");
	rast = rt_raster_new(width, height);
	if (NULL == rast) {
		rterror("rt_raster_from_gdal_dataset: Out of memory allocating new raster");
		return NULL;
	}
	RASTER_DEBUGF(3, "Created raster dimensions (width x height): %d x %d", rast->width, rast->height);

	/* get raster attributes */
	cplerr = GDALGetGeoTransform(ds, gt);
	if (cplerr != CE_None) {
		rterror("rt_raster_from_gdal_dataset: Unable to get geotransformation");
		rt_raster_destroy(rast);
		return NULL;
	}
	RASTER_DEBUGF(3, "Raster geotransform (%f, %f, %f, %f, %f, %f)",
		gt[0], gt[1], gt[2], gt[3], gt[4], gt[5]);

	/* apply raster attributes */
	rt_raster_set_geotransform_matrix(rast, gt);

	/* srid */
	srs = GDALGetProjectionRef(ds);
	if (srs != NULL && srs[0] != '\0') {
		OGRSpatialReferenceH hSRS = OSRNewSpatialReference(NULL);
		if (OSRSetFromUserInput(hSRS, srs) == OGRERR_NONE) {
			const char* pszAuthorityName = OSRGetAuthorityName(hSRS, NULL);
			const char* pszAuthorityCode = OSRGetAuthorityCode(hSRS, NULL);
			if (
				pszAuthorityName != NULL &&
				strcmp(pszAuthorityName, "EPSG") == 0 &&
				pszAuthorityCode != NULL
			) {
				rt_raster_set_srid(rast, atoi(pszAuthorityCode));
			}
		}
		OSRDestroySpatialReference(hSRS);
	}

	/* copy bands */
	numBands = GDALGetRasterCount(ds);
	for (i = 1; i <= numBands; i++) {
		RASTER_DEBUGF(3, "Processing band %d of %d", i, numBands);
		gdband = NULL;
		gdband = GDALGetRasterBand(ds, i);
		if (NULL == gdband) {
			rterror("rt_raster_from_gdal_dataset: Unable to get GDAL band");
			rt_raster_destroy(rast);
			return NULL;
		}

		/* pixtype */
		gdpixtype = GDALGetRasterDataType(gdband);
		pt = rt_util_gdal_datatype_to_pixtype(gdpixtype);
		if (pt == PT_END) {
			rterror("rt_raster_from_gdal_dataset: Unknown pixel type for GDAL band");
			rt_raster_destroy(rast);
			return NULL;
		}
		ptlen = rt_pixtype_size(pt);

		/* size: width and height */
		width = GDALGetRasterBandXSize(gdband);
		height = GDALGetRasterBandYSize(gdband);
		RASTER_DEBUGF(3, "Band dimensions (width x height): %d x %d", width, height);

		/* nodata */
		nodataval = GDALGetRasterNoDataValue(gdband, &status);
		if (!status) {
			nodataval = 0;
			hasnodata = 0;
		}
		else
			hasnodata = 1;
		RASTER_DEBUGF(3, "(hasnodata, nodataval) = (%d, %f)", hasnodata, nodataval);

		/* create band object */
		idx = rt_raster_generate_new_band(
			rast, pt,
			(hasnodata ? nodataval : 0),
			hasnodata, nodataval, rt_raster_get_num_bands(rast)
		);
		if (idx < 0) {
			rterror("rt_raster_from_gdal_dataset: Could not allocate memory for raster band");
			rt_raster_destroy(rast);
			return NULL;
		}
		band = rt_raster_get_band(rast, idx);
		RASTER_DEBUGF(3, "Created band of dimension (width x height): %d x %d", band->width, band->height);

		/* this makes use of GDAL's "natural" blocks */
		GDALGetBlockSize(gdband, &nXBlockSize, &nYBlockSize);
		nXBlocks = (width + nXBlockSize - 1) / nXBlockSize;
		nYBlocks = (height + nYBlockSize - 1) / nYBlockSize;
		RASTER_DEBUGF(4, "(nXBlockSize, nYBlockSize) = (%d, %d)", nXBlockSize, nYBlockSize);
		RASTER_DEBUGF(4, "(nXBlocks, nYBlocks) = (%d, %d)", nXBlocks, nYBlocks);

		/* allocate memory for values */
		valueslen = ptlen * nXBlockSize * nYBlockSize;
		switch (gdpixtype) {
			case GDT_Byte:
				values = (uint8_t *) rtalloc(valueslen);
				break;
			case GDT_UInt16:
				values = (uint16_t *) rtalloc(valueslen);
				break;
			case GDT_Int16:
				values = (int16_t *) rtalloc(valueslen);
				break;
			case GDT_UInt32:
				values = (uint32_t *) rtalloc(valueslen);
				break;
			case GDT_Int32:
				values = (int32_t *) rtalloc(valueslen);
				break;
			case GDT_Float32:
				values = (float *) rtalloc(valueslen);
				break;
			case GDT_Float64:
				values = (double *) rtalloc(valueslen);
				break;
			default:
				/* should NEVER get here */
				rterror("rt_raster_from_gdal_dataset: Could not allocate memory for unknown pixel type");
				rt_raster_destroy(rast);
				return NULL;
		}
		if (values == NULL) {
			rterror("rt_raster_from_gdal_dataset: Could not allocate memory for GDAL band pixel values");
			rt_raster_destroy(rast);
			return NULL;
		}

		for (iYBlock = 0; iYBlock < nYBlocks; iYBlock++) {
			for (iXBlock = 0; iXBlock < nXBlocks; iXBlock++) {
				memset(values, 0, valueslen);

				x = iXBlock * nXBlockSize;
				y = iYBlock * nYBlockSize;
				RASTER_DEBUGF(4, "(iXBlock, iYBlock) = (%d, %d)", iXBlock, iYBlock);
				RASTER_DEBUGF(4, "(x, y) = (%d, %d)", x, y);

				/* valid block width */
				if ((iXBlock + 1) * nXBlockSize > width)
					nXValid = width - (iXBlock * nXBlockSize);
				else
					nXValid = nXBlockSize;

				/* valid block height */
				if ((iYBlock + 1) * nYBlockSize > height)
					nYValid = height - (iYBlock * nYBlockSize);
				else
					nYValid = nYBlockSize;

				RASTER_DEBUGF(4, "(nXValid, nYValid) = (%d, %d)", nXValid, nYValid);

				cplerr = GDALRasterIO(
					gdband, GF_Read,
					x, y,
					nXValid, nYValid,
					values, nXValid, nYValid,
					gdpixtype,
					0, 0
				);
				if (cplerr != CE_None) {
					rterror("rt_raster_from_gdal_dataset: Unable to get data from transformed raster");
					rtdealloc(values);
					rt_raster_destroy(rast);
					return NULL;
				}

				/* if block width is same as raster width, shortcut */
				if (nXBlocks == 1 && nYBlockSize > 1 && nXValid == width) {
					x = 0;
					y = nYBlockSize * iYBlock;

					RASTER_DEBUGF(4, "Setting set of pixel lines at (%d, %d) for %d pixels", x, y, nXValid * nYValid);
					rt_band_set_pixel_line(band, x, y, values, nXValid * nYValid);
				}
				else {
					ptr = values;
					x = nXBlockSize * iXBlock;
					for (iY = 0; iY < nYValid; iY++) {
						y = iY + (nYBlockSize * iYBlock);

						RASTER_DEBUGF(4, "Setting pixel line at (%d, %d) for %d pixels", x, y, nXValid);
						rt_band_set_pixel_line(band, x, y, ptr, nXValid);
						ptr += (nXValid * ptlen);
					}
				}
			}
		}

		/* free memory */
		rtdealloc(values);
	}

	return rast;
}

/**
 * Return a warped raster using GDAL Warp API
 *
 * @param raster : raster to transform
 * @param src_srs : the raster's coordinate system in OGC WKT
 * @param dst_srs : the warped raster's coordinate system in OGC WKT
 * @param scale_x : the x size of pixels of the warped raster's pixels in
 *   units of dst_srs
 * @param scale_y : the y size of pixels of the warped raster's pixels in
 *   units of dst_srs
 * @param width : the number of columns of the warped raster.  note that
 *   width/height CANNOT be used with scale_x/scale_y
 * @param height : the number of rows of the warped raster.  note that
 *   width/height CANNOT be used with scale_x/scale_y
 * @param ul_xw : the X value of upper-left corner of the warped raster in
 *   units of dst_srs
 * @param ul_yw : the Y value of upper-left corner of the warped raster in
 *   units of dst_srs
 * @param grid_xw : the X value of point on a grid to align warped raster
 *   to in units of dst_srs
 * @param grid_yw : the Y value of point on a grid to align warped raster
 *   to in units of dst_srs
 * @param skew_x : the X skew of the warped raster in units of dst_srs
 * @param skew_y : the Y skew of the warped raster in units of dst_srs
 * @param resample_alg : the resampling algorithm
 * @param max_err : maximum error measured in input pixels permitted
 *   (0.0 for exact calculations)
 *
 * @return the warped raster
 */
rt_raster rt_raster_gdal_warp(
	rt_raster raster, const char *src_srs,
	const char *dst_srs,
	double *scale_x, double *scale_y,
	int *width, int *height,
	double *ul_xw, double *ul_yw,
	double *grid_xw, double *grid_yw,
	double *skew_x, double *skew_y,
	GDALResampleAlg resample_alg, double max_err
) {
	CPLErr cplerr;
	GDALDriverH src_drv = NULL;
	GDALDatasetH src_ds = NULL;
	GDALWarpOptions *wopts = NULL;
	GDALDriverH dst_drv = NULL;
	GDALDatasetH dst_ds = NULL;
	char *_src_srs = NULL;
	char *_dst_srs = NULL;
	char *dst_options[] = {"SUBCLASS=VRTWarpedDataset", NULL};
	char **transform_opts = NULL;
	int transform_opts_len = 2;
	void *transform_arg = NULL;
	void *imgproj_arg = NULL;
	void *approx_arg = NULL;
	GDALTransformerFunc transform_func = NULL;

	GDALRasterBandH band;
	rt_band rtband = NULL;
	rt_pixtype pt = PT_END;
	GDALDataType gdal_pt = GDT_Unknown;
	double nodata = 0.0;

	double _gt[6] = {0};
	double dst_extent[4];
	rt_envelope extent;

	int _dim[2] = {0};
	double _skew[2] = {0};
	double _scale[2] = {0};
	int ul_user = 0;

	rt_raster rast = NULL;
	int i = 0;
	int j = 0;
	int numBands = 0;

	RASTER_DEBUG(3, "starting");

	assert(NULL != raster);
	assert(NULL != src_srs);

	/*
		max_err must be gte zero

		the value 0.125 is the default used in gdalwarp.cpp on line 283
	*/
	if (max_err < 0.) max_err = 0.125;
	RASTER_DEBUGF(4, "max_err = %f", max_err);

	_src_srs = rt_util_gdal_convert_sr(src_srs, 0);
	/* dst_srs not provided, set to src_srs */
	if (NULL == dst_srs)
		_dst_srs = rt_util_gdal_convert_sr(src_srs, 0);
	else
		_dst_srs = rt_util_gdal_convert_sr(dst_srs, 0);

	/* load raster into a GDAL MEM dataset */
	src_ds = rt_raster_to_gdal_mem(raster, _src_srs, NULL, 0, &src_drv);
	if (NULL == src_ds) {
		rterror("rt_raster_gdal_warp: Unable to convert raster to GDAL MEM format");

		CPLFree(_src_srs);
		CPLFree(_dst_srs);

		return NULL;
	}
	RASTER_DEBUG(3, "raster loaded into GDAL MEM dataset");

	/* set transform_opts */
	transform_opts = (char **) rtalloc(sizeof(char *) * (transform_opts_len + 1));
	if (NULL == transform_opts) {
		rterror("rt_raster_gdal_warp: Unable to allocation memory for transform options");

		GDALClose(src_ds);

		CPLFree(_src_srs);
		CPLFree(_dst_srs);

		return NULL;
	}
	for (i = 0; i < transform_opts_len; i++) {
		switch (i) {
			case 1:
				transform_opts[i] = (char *) rtalloc(sizeof(char) * (strlen("DST_SRS=") + strlen(_dst_srs) + 1));
				break;
			case 0:
				transform_opts[i] = (char *) rtalloc(sizeof(char) * (strlen("SRC_SRS=") + strlen(_src_srs) + 1));
				break;
		}
		if (NULL == transform_opts[i]) {
			rterror("rt_raster_gdal_warp: Unable to allocation memory for transform options");

			for (j = 0; j < i; j++) rtdealloc(transform_opts[j]);
			rtdealloc(transform_opts);
			GDALClose(src_ds);

			CPLFree(_src_srs);
			CPLFree(_dst_srs);

			return NULL;
		}

		switch (i) {
			case 1:
				snprintf(
					transform_opts[i],
					sizeof(char) * (strlen("DST_SRS=") + strlen(_dst_srs) + 1),
					"DST_SRS=%s",
					_dst_srs
				);
				break;
			case 0:
				snprintf(
					transform_opts[i],
					sizeof(char) * (strlen("SRC_SRS=") + strlen(_src_srs) + 1),
					"SRC_SRS=%s",
					_src_srs
				);
				break;
		}
		RASTER_DEBUGF(4, "transform_opts[%d] = %s", i, transform_opts[i]);
	}
	transform_opts[transform_opts_len] = NULL;
	CPLFree(_src_srs);
	CPLFree(_dst_srs);

	/* transformation object for building dst dataset */
	transform_arg = GDALCreateGenImgProjTransformer2(src_ds, NULL, transform_opts);
	if (NULL == transform_arg) {
		rterror("rt_raster_gdal_warp: Unable to create GDAL transformation object for output dataset creation");

		GDALClose(src_ds);

		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}

	/* get approximate output georeferenced bounds and resolution */
	cplerr = GDALSuggestedWarpOutput2(src_ds, GDALGenImgProjTransform,
		transform_arg, _gt, &(_dim[0]), &(_dim[1]), dst_extent, 0);
	GDALDestroyGenImgProjTransformer(transform_arg);
	if (cplerr != CE_None) {
		rterror("rt_raster_gdal_warp: Unable to get GDAL suggested warp output for output dataset creation");

		GDALClose(src_ds);

		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}

	/*
		don't use suggested dimensions as use of suggested scales
		on suggested extent will result in suggested dimensions
	*/
	_dim[0] = 0;
	_dim[1] = 0;

	RASTER_DEBUGF(3, "Suggested geotransform: %f, %f, %f, %f, %f, %f",
		_gt[0], _gt[1], _gt[2], _gt[3], _gt[4], _gt[5]);

	/* store extent in easier-to-use object */
	extent.MinX = dst_extent[0];
	extent.MinY = dst_extent[1];
	extent.MaxX = dst_extent[2];
	extent.MaxY = dst_extent[3];

	extent.UpperLeftX = dst_extent[0];
	extent.UpperLeftY = dst_extent[3];

	RASTER_DEBUGF(3, "Suggested extent: %f, %f, %f, %f",
		extent.MinX, extent.MinY, extent.MaxX, extent.MaxY);

	/* scale and width/height are mutually exclusive */
	if (
		((NULL != scale_x) || (NULL != scale_y)) &&
		((NULL != width) || (NULL != height))
	) {
		rterror("rt_raster_gdal_warp: Scale X/Y and width/height are mutually exclusive.  Only provide one");

		GDALClose(src_ds);

		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}

	/* user-defined width */
	if (NULL != width) {
		_dim[0] = abs(*width);
		_scale[0] = fabs((extent.MaxX - extent.MinX) / ((double) _dim[0]));
	}
	/* user-defined height */
	if (NULL != height) {
		_dim[1] = abs(*height);
		_scale[1] = fabs((extent.MaxY - extent.MinY) / ((double) _dim[1]));
	}

	/* user-defined scale */
	if (
		((NULL != scale_x) && (FLT_NEQ(*scale_x, 0.0))) &&
		((NULL != scale_y) && (FLT_NEQ(*scale_y, 0.0)))
	) {
		_scale[0] = fabs(*scale_x);
		_scale[1] = fabs(*scale_y);
	}
	else if (
		((NULL != scale_x) && (NULL == scale_y)) ||
		((NULL == scale_x) && (NULL != scale_y))
	) {
		rterror("rt_raster_gdal_warp: Both X and Y scale values must be provided for scale");

		GDALClose(src_ds);

		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}

	/* scale not defined, use suggested */
	if (FLT_EQ(_scale[0], 0) && FLT_EQ(_scale[1], 0)) {
		_scale[0] = fabs(_gt[1]);
		_scale[1] = fabs(_gt[5]);
	}

	RASTER_DEBUGF(4, "Using scale: %f x %f", _scale[0], -1 * _scale[1]);

	/* user-defined skew */
	if (NULL != skew_x) {
		_skew[0] = *skew_x;

		/*
			negative scale-x affects skew
			for now, force skew to be in left-right, top-down orientation
		*/
		if (
			NULL != scale_x &&
			*scale_x < 0.
		) {
			_skew[0] *= -1;
		}
	}
	if (NULL != skew_y) {
		_skew[1] = *skew_y;

		/*
			positive scale-y affects skew
			for now, force skew to be in left-right, top-down orientation
		*/
		if (
			NULL != scale_y &&
			*scale_y > 0.
		) {
			_skew[1] *= -1;
		}
	}

	RASTER_DEBUGF(4, "Using skew: %f x %f", _skew[0], _skew[1]);

	/* reprocess extent if skewed */
	if (
		FLT_NEQ(_skew[0], 0) ||
		FLT_NEQ(_skew[1], 0)
	) {
		rt_raster skewedrast;

		RASTER_DEBUG(3, "Computing skewed extent's envelope");

		skewedrast = rt_raster_compute_skewed_raster(
			extent,
			_skew,
			_scale,
			0.01
		);
		if (skewedrast == NULL) {
			rterror("rt_raster_gdal_warp: Could not compute skewed raster");

			GDALClose(src_ds);

			for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
			rtdealloc(transform_opts);

			return NULL;
		}

		if (_dim[0] == 0)
			_dim[0] = skewedrast->width;
		if (_dim[1] == 0)
			_dim[1] = skewedrast->height;

		extent.UpperLeftX = skewedrast->ipX;
		extent.UpperLeftY = skewedrast->ipY;

		rt_raster_destroy(skewedrast);
	}

	/* dimensions not defined, compute */
	if (!_dim[0])
		_dim[0] = (int) fmax((fabs(extent.MaxX - extent.MinX) + (_scale[0] / 2.)) / _scale[0], 1);
	if (!_dim[1])
		_dim[1] = (int) fmax((fabs(extent.MaxY - extent.MinY) + (_scale[1] / 2.)) / _scale[1], 1);

	/* temporary raster */
	rast = rt_raster_new(_dim[0], _dim[1]);
	if (rast == NULL) {
		rterror("rt_raster_gdal_warp: Out of memory allocating temporary raster");

		GDALClose(src_ds);

		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}

	/* set raster's spatial attributes */
	rt_raster_set_offsets(rast, extent.UpperLeftX, extent.UpperLeftY);
	rt_raster_set_scale(rast, _scale[0], -1 * _scale[1]);
	rt_raster_set_skews(rast, _skew[0], _skew[1]);

	rt_raster_get_geotransform_matrix(rast, _gt);
	RASTER_DEBUGF(3, "Temp raster's geotransform: %f, %f, %f, %f, %f, %f",
		_gt[0], _gt[1], _gt[2], _gt[3], _gt[4], _gt[5]);
	RASTER_DEBUGF(3, "Temp raster's dimensions (width x height): %d x %d",
		_dim[0], _dim[1]);

	/* user-defined upper-left corner */
	if (
		NULL != ul_xw &&
		NULL != ul_yw
	) {
		ul_user = 1;

		RASTER_DEBUGF(4, "Using user-specified upper-left corner: %f, %f", *ul_xw, *ul_yw);

		/* set upper-left corner */
		rt_raster_set_offsets(rast, *ul_xw, *ul_yw);
		extent.UpperLeftX = *ul_xw;
		extent.UpperLeftY = *ul_yw;
	}
	else if (
		((NULL != ul_xw) && (NULL == ul_yw)) ||
		((NULL == ul_xw) && (NULL != ul_yw))
	) {
		rterror("rt_raster_gdal_warp: Both X and Y upper-left corner values must be provided");

		rt_raster_destroy(rast);
		GDALClose(src_ds);

		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}

	/* alignment only considered if upper-left corner not provided */
	if (
		!ul_user && (
			(NULL != grid_xw) || (NULL != grid_yw)
		)
	) {

		if (
			((NULL != grid_xw) && (NULL == grid_yw)) ||
			((NULL == grid_xw) && (NULL != grid_yw))
		) {
			rterror("rt_raster_gdal_warp: Both X and Y alignment values must be provided");

			rt_raster_destroy(rast);
			GDALClose(src_ds);

			for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
			rtdealloc(transform_opts);

			return NULL;
		}

		RASTER_DEBUGF(4, "Aligning extent to user-specified grid: %f, %f", *grid_xw, *grid_yw);

		do {
			double _r[2] = {0};
			double _w[2] = {0};

			/* raster is already aligned */
			if (FLT_EQ(*grid_xw, extent.UpperLeftX) && FLT_EQ(*grid_yw, extent.UpperLeftY)) {
				RASTER_DEBUG(3, "Skipping raster alignment as it is already aligned to grid");
				break;
			}

			extent.UpperLeftX = rast->ipX;
			extent.UpperLeftY = rast->ipY;
			rt_raster_set_offsets(rast, *grid_xw, *grid_yw);

			/* process upper-left corner */
			if (!rt_raster_geopoint_to_cell(
				rast,
				extent.UpperLeftX, extent.UpperLeftY,
				&(_r[0]), &(_r[1]),
				NULL
			)) {
				rterror("rt_raster_gdal_warp: Unable to compute raster pixel for spatial coordinates");

				rt_raster_destroy(rast);
				GDALClose(src_ds);

				for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
				rtdealloc(transform_opts);

				return NULL;
			}

			if (!rt_raster_cell_to_geopoint(
				rast,
				_r[0], _r[1],
				&(_w[0]), &(_w[1]),
				NULL
			)) {
				rterror("rt_raster_gdal_warp: Unable to compute spatial coordinates for raster pixel");

				rt_raster_destroy(rast);
				GDALClose(src_ds);

				for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
				rtdealloc(transform_opts);

				return NULL;
			}

			/* shift occurred */
			if (FLT_NEQ(_w[0], extent.UpperLeftX)) {
				if (NULL == width)
					rast->width++;
				else if (NULL == scale_x) {
					double _c[2] = {0};

					rt_raster_set_offsets(rast, extent.UpperLeftX, extent.UpperLeftY);

					/* get upper-right corner */
					if (!rt_raster_cell_to_geopoint(
						rast,
						rast->width, 0,
						&(_c[0]), &(_c[1]),
						NULL
					)) {
						rterror("rt_raster_gdal_warp: Unable to compute spatial coordinates for raster pixel");

						rt_raster_destroy(rast);
						GDALClose(src_ds);

						for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
						rtdealloc(transform_opts);

						return NULL;
					}

					rast->scaleX = fabs((_c[0] - _w[0]) / ((double) rast->width));
				}
			}
			if (FLT_NEQ(_w[1], extent.UpperLeftY)) {
				if (NULL == height)
					rast->height++;
				else if (NULL == scale_y) {
					double _c[2] = {0};

					rt_raster_set_offsets(rast, extent.UpperLeftX, extent.UpperLeftY);

					/* get upper-right corner */
					if (!rt_raster_cell_to_geopoint(
						rast,
						0, rast->height,
						&(_c[0]), &(_c[1]),
						NULL
					)) {
						rterror("rt_raster_gdal_warp: Unable to compute spatial coordinates for raster pixel");

						rt_raster_destroy(rast);
						GDALClose(src_ds);

						for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
						rtdealloc(transform_opts);

						return NULL;
					}

					rast->scaleY = -1 * fabs((_c[1] - _w[1]) / ((double) rast->height));
				}
			}

			rt_raster_set_offsets(rast, _w[0], _w[1]);
			RASTER_DEBUGF(4, "aligned offsets: %f x %f", _w[0], _w[1]);
		}
		while (0);
	}

	/*
		after this point, rt_envelope extent is no longer used
	*/

	/* get key attributes from rast */
	_dim[0] = rast->width;
	_dim[1] = rast->height;
	rt_raster_get_geotransform_matrix(rast, _gt);

	/* scale-x is negative or scale-y is positive */
	if ((
		(NULL != scale_x) && (*scale_x < 0.)
	) || (
		(NULL != scale_y) && (*scale_y > 0)
	)) {
		double _w[2] = {0};

		/* negative scale-x */
		if (
			(NULL != scale_x) &&
			(*scale_x < 0.)
		) {
			if (!rt_raster_cell_to_geopoint(
				rast,
				rast->width, 0,
				&(_w[0]), &(_w[1]),
				NULL
			)) {
				rterror("rt_raster_gdal_warp: Unable to compute spatial coordinates for raster pixel");

				rt_raster_destroy(rast);

				GDALClose(src_ds);

				for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
				rtdealloc(transform_opts);

				return NULL;
			}

			_gt[0] = _w[0];
			_gt[1] = *scale_x;

			/* check for skew */
			if (NULL != skew_x && FLT_NEQ(*skew_x, 0))
				_gt[2] = *skew_x;
		}
		/* positive scale-y */
		if (
			(NULL != scale_y) &&
			(*scale_y > 0)
		) {
			if (!rt_raster_cell_to_geopoint(
				rast,
				0, rast->height,
				&(_w[0]), &(_w[1]),
				NULL
			)) {
				rterror("rt_raster_gdal_warp: Unable to compute spatial coordinates for raster pixel");

				rt_raster_destroy(rast);

				GDALClose(src_ds);

				for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
				rtdealloc(transform_opts);

				return NULL;
			}

			_gt[3] = _w[1];
			_gt[5] = *scale_y;

			/* check for skew */
			if (NULL != skew_y && FLT_NEQ(*skew_y, 0))
				_gt[4] = *skew_y;
		}
	}

	rt_raster_destroy(rast);
	rast = NULL;

	RASTER_DEBUGF(3, "Applied geotransform: %f, %f, %f, %f, %f, %f",
		_gt[0], _gt[1], _gt[2], _gt[3], _gt[4], _gt[5]);
	RASTER_DEBUGF(3, "Raster dimensions (width x height): %d x %d",
		_dim[0], _dim[1]);

	if (FLT_EQ(_dim[0], 0) || FLT_EQ(_dim[1], 0)) {
		rterror("rt_raster_gdal_warp: The width (%f) or height (%f) of the warped raster is zero", _dim[0], _dim[1]);

		GDALClose(src_ds);

		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}

	/* load VRT driver */
	if (!rt_util_gdal_driver_registered("VRT"))
		GDALRegister_VRT();
	dst_drv = GDALGetDriverByName("VRT");
	if (NULL == dst_drv) {
		rterror("rt_raster_gdal_warp: Unable to load the output GDAL VRT driver");

		GDALClose(src_ds);

		return NULL;
	}

	/* create dst dataset */
	dst_ds = GDALCreate(dst_drv, "", _dim[0], _dim[1], 0, GDT_Byte, dst_options);
	if (NULL == dst_ds) {
		rterror("rt_raster_gdal_warp: Unable to create GDAL VRT dataset");

		GDALClose(src_ds);

		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}

	/* add bands to dst dataset */
	numBands = rt_raster_get_num_bands(raster);
	for (i = 0; i < numBands; i++) {
		rtband = rt_raster_get_band(raster, i);
		if (NULL == rtband) {
			rterror("rt_raster_gdal_warp: Unable to get band %d for adding to VRT dataset", i);

			GDALClose(dst_ds);
			GDALClose(src_ds);

			for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
			rtdealloc(transform_opts);

			return NULL;
		}

		pt = rt_band_get_pixtype(rtband);
		gdal_pt = rt_util_pixtype_to_gdal_datatype(pt);
		if (gdal_pt == GDT_Unknown)
			rtwarn("rt_raster_gdal_warp: Unknown pixel type for band %d", i);

		cplerr = GDALAddBand(dst_ds, gdal_pt, NULL);
		if (cplerr != CE_None) {
			rterror("rt_raster_gdal_warp: Unable to add band to VRT dataset");

			GDALClose(dst_ds);
			GDALClose(src_ds);

			for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
			rtdealloc(transform_opts);

			return NULL;
		}

		/* get band to write data to */
		band = NULL;
		band = GDALGetRasterBand(dst_ds, i + 1);
		if (NULL == band) {
			rterror("rt_raster_gdal_warp: Could not get GDAL band for additional processing");

			GDALClose(dst_ds);
			GDALClose(src_ds);

			for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
			rtdealloc(transform_opts);

			return NULL;
		}

		/* set nodata */
		if (rt_band_get_hasnodata_flag(rtband) != FALSE) {
			nodata = rt_band_get_nodata(rtband);
			if (GDALSetRasterNoDataValue(band, nodata) != CE_None)
				rtwarn("rt_raster_gdal_warp: Could not set nodata value for band %d", i);
			RASTER_DEBUGF(3, "nodata value set to %f", GDALGetRasterNoDataValue(band, NULL));
		}
	}

	/* set dst srs */
	_dst_srs = rt_util_gdal_convert_sr((NULL == dst_srs ? src_srs : dst_srs), 1);
	cplerr = GDALSetProjection(dst_ds, _dst_srs);
	CPLFree(_dst_srs);
	if (cplerr != CE_None) {
		rterror("rt_raster_gdal_warp: Unable to set projection");

		GDALClose(dst_ds);
		GDALClose(src_ds);

		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}

	/* set dst geotransform */
	cplerr = GDALSetGeoTransform(dst_ds, _gt);
	if (cplerr != CE_None) {
		rterror("rt_raster_gdal_warp: Unable to set geotransform");

		GDALClose(dst_ds);
		GDALClose(src_ds);

		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}

	/* create transformation object */
	transform_arg = imgproj_arg = GDALCreateGenImgProjTransformer2(src_ds, dst_ds, transform_opts);
	if (NULL == transform_arg) {
		rterror("rt_raster_gdal_warp: Unable to create GDAL transformation object");

		GDALClose(dst_ds);
		GDALClose(src_ds);

		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}
	transform_func = GDALGenImgProjTransform;

	/* use approximate transformation object */
	if (max_err > 0.0) {
		transform_arg = approx_arg = GDALCreateApproxTransformer(
			GDALGenImgProjTransform,
			imgproj_arg, max_err
		);
		if (NULL == transform_arg) {
			rterror("rt_raster_gdal_warp: Unable to create GDAL approximate transformation object");

			GDALClose(dst_ds);
			GDALClose(src_ds);

			GDALDestroyGenImgProjTransformer(imgproj_arg);
			for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
			rtdealloc(transform_opts);

			return NULL;
		}

		transform_func = GDALApproxTransform;
	}

	/* warp options */
	wopts = GDALCreateWarpOptions();
	if (NULL == wopts) {
		rterror("rt_raster_gdal_warp: Unable to create GDAL warp options object");

		GDALClose(dst_ds);
		GDALClose(src_ds);

		GDALDestroyGenImgProjTransformer(imgproj_arg);
		GDALDestroyApproxTransformer(approx_arg);
		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}

	/* set options */
	wopts->eResampleAlg = resample_alg;
	wopts->hSrcDS = src_ds;
	wopts->hDstDS = dst_ds;
	wopts->pfnTransformer = transform_func;
	wopts->pTransformerArg = transform_arg;
	wopts->papszWarpOptions = (char **) CPLMalloc(sizeof(char *) * 2);
	wopts->papszWarpOptions[0] = (char *) CPLMalloc(sizeof(char) * (strlen("INIT_DEST=NO_DATA") + 1));
	strcpy(wopts->papszWarpOptions[0], "INIT_DEST=NO_DATA");
	wopts->papszWarpOptions[1] = NULL;

	/* set band mapping */
	wopts->nBandCount = numBands;
	wopts->panSrcBands = (int *) CPLMalloc(sizeof(int) * wopts->nBandCount);
	wopts->panDstBands = (int *) CPLMalloc(sizeof(int) * wopts->nBandCount);
	for (i = 0; i < wopts->nBandCount; i++)
		wopts->panDstBands[i] = wopts->panSrcBands[i] = i + 1;

	/* set nodata mapping */
	RASTER_DEBUG(3, "Setting nodata mapping");
	wopts->padfSrcNoDataReal = (double *) CPLMalloc(numBands * sizeof(double));
	wopts->padfDstNoDataReal = (double *) CPLMalloc(numBands * sizeof(double));
	wopts->padfSrcNoDataImag = (double *) CPLMalloc(numBands * sizeof(double));
	wopts->padfDstNoDataImag = (double *) CPLMalloc(numBands * sizeof(double));
	if (
		NULL == wopts->padfSrcNoDataReal ||
		NULL == wopts->padfDstNoDataReal ||
		NULL == wopts->padfSrcNoDataImag ||
		NULL == wopts->padfDstNoDataImag
	) {
		rterror("rt_raster_gdal_warp: Out of memory allocating nodata mapping");

		GDALClose(dst_ds);
		GDALClose(src_ds);

		GDALDestroyGenImgProjTransformer(imgproj_arg);
		GDALDestroyApproxTransformer(approx_arg);
		GDALDestroyWarpOptions(wopts);
		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}
	for (i = 0; i < numBands; i++) {
		band = rt_raster_get_band(raster, i);
		if (!band) {
			rterror("rt_raster_gdal_warp: Unable to process bands for nodata values");

			GDALClose(dst_ds);
			GDALClose(src_ds);

			GDALDestroyGenImgProjTransformer(imgproj_arg);
			GDALDestroyApproxTransformer(approx_arg);
			GDALDestroyWarpOptions(wopts);
			for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
			rtdealloc(transform_opts);

			return NULL;
		}

		if (!rt_band_get_hasnodata_flag(band)) {
			/*
				based on line 1004 of gdalwarp.cpp
				the problem is that there is a chance that this number is a legitimate value
			*/
			wopts->padfSrcNoDataReal[i] = -123456.789;
		}
		else {
			wopts->padfSrcNoDataReal[i] = rt_band_get_nodata(band);
		}

		wopts->padfDstNoDataReal[i] = wopts->padfSrcNoDataReal[i];
		wopts->padfDstNoDataImag[i] = wopts->padfSrcNoDataImag[i] = 0.0;
		RASTER_DEBUGF(4, "Mapped nodata value for band %d: %f (%f) => %f (%f)",
			i,
			wopts->padfSrcNoDataReal[i], wopts->padfSrcNoDataImag[i],
			wopts->padfDstNoDataReal[i], wopts->padfDstNoDataImag[i]
		);
	}

	/* warp raster */
	RASTER_DEBUG(3, "Warping raster");
	cplerr = GDALInitializeWarpedVRT(dst_ds, wopts);
	if (cplerr != CE_None) {
		rterror("rt_raster_gdal_warp: Unable to warp raster");

		GDALClose(dst_ds);
		GDALClose(src_ds);

		if ((transform_func == GDALApproxTransform) && (NULL != imgproj_arg))
			GDALDestroyGenImgProjTransformer(imgproj_arg);
		GDALDestroyWarpOptions(wopts);
		for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
		rtdealloc(transform_opts);

		return NULL;
	}
	GDALFlushCache(dst_ds);
	RASTER_DEBUG(3, "Raster warped");

	/* convert gdal dataset to raster */
	RASTER_DEBUG(3, "Converting GDAL dataset to raster");
	rast = rt_raster_from_gdal_dataset(dst_ds);

	GDALClose(dst_ds);
	GDALClose(src_ds);

	if ((transform_func == GDALApproxTransform) && (NULL != imgproj_arg))
		GDALDestroyGenImgProjTransformer(imgproj_arg);
	GDALDestroyWarpOptions(wopts);
	for (i = 0; i < transform_opts_len; i++) rtdealloc(transform_opts[i]);
	rtdealloc(transform_opts);

	if (NULL == rast) {
		rterror("rt_raster_gdal_warp: Unable to warp raster");
		return NULL;
	}

	RASTER_DEBUG(3, "done");

	return rast;
}

/**
 * Return a raster of the provided geometry
 *
 * @param wkb : WKB representation of the geometry to convert
 * @param wkb_len : length of the WKB representation of the geometry
 * @param srs : the geometry's coordinate system in OGC WKT
 * @param num_bands: number of bands in the output raster
 * @param pixtype: data type of each band
 * @param init: array of values to initialize each band with
 * @param value: array of values for pixels of geometry
 * @param nodata: array of nodata values for each band
 * @param hasnodata: array flagging the presence of nodata for each band
 * @param width : the number of columns of the raster
 * @param height : the number of rows of the raster
 * @param scale_x : the pixel width of the raster
 * @param scale_y : the pixel height of the raster
 * @param ul_xw : the X value of upper-left corner of the raster
 * @param ul_yw : the Y value of upper-left corner of the raster
 * @param grid_xw : the X value of point on grid to align raster to
 * @param grid_yw : the Y value of point on grid to align raster to
 * @param skew_x : the X skew of the raster
 * @param skew_y : the Y skew of the raster
 * @param options : array of options.  only option is "ALL_TOUCHED"
 *
 * @return the raster of the provided geometry
 */
rt_raster
rt_raster_gdal_rasterize(const unsigned char *wkb,
	uint32_t wkb_len, const char *srs,
	uint32_t num_bands, rt_pixtype *pixtype,
	double *init, double *value,
	double *nodata, uint8_t *hasnodata,
	int *width, int *height,
	double *scale_x, double *scale_y,
	double *ul_xw, double *ul_yw,
	double *grid_xw, double *grid_yw,
	double *skew_x, double *skew_y,
	char **options
) {
	rt_raster rast;
	int i = 0;
	int noband = 0;
	int banderr = 0;
	int *band_list = NULL;

	rt_pixtype *_pixtype = NULL;
	double *_init = NULL;
	double *_nodata = NULL;
	uint8_t *_hasnodata = NULL;
	double *_value = NULL;

	int _dim[2] = {0};
	double _scale[2] = {0};
	double _skew[2] = {0};

	OGRErr ogrerr;
	OGRSpatialReferenceH src_sr = NULL;
	OGRGeometryH src_geom;
	OGREnvelope src_env;
	rt_envelope extent;
	OGRwkbGeometryType wkbtype = wkbUnknown;

	int ul_user = 0;

	CPLErr cplerr;
	double _gt[6] = {0};
	GDALDriverH _drv = NULL;
	GDALDatasetH _ds = NULL;
	GDALRasterBandH _band = NULL;

	RASTER_DEBUG(3, "starting");

	assert(NULL != wkb);
	assert(0 != wkb_len);

	/* internal aliases */
	_pixtype = pixtype;
	_init = init;
	_nodata = nodata;
	_hasnodata = hasnodata;
	_value = value;

	/* no bands, raster is a mask */
	if (num_bands < 1) {
		num_bands = 1;
		noband = 1;

		_pixtype = (rt_pixtype *) rtalloc(sizeof(rt_pixtype));
		*_pixtype = PT_8BUI;

		_init = (double *) rtalloc(sizeof(double));
		*_init = 0;

		_nodata = (double *) rtalloc(sizeof(double));
		*_nodata = 0;

		_hasnodata = (uint8_t *) rtalloc(sizeof(uint8_t));
		*_hasnodata = 1;

		_value = (double *) rtalloc(sizeof(double));
		*_value = 1;
	}

	assert(NULL != _pixtype);
	assert(NULL != _init);
	assert(NULL != _nodata);
	assert(NULL != _hasnodata);

	/* OGR spatial reference */
	if (NULL != srs && strlen(srs)) {
		src_sr = OSRNewSpatialReference(NULL);
		if (OSRSetFromUserInput(src_sr, srs) != OGRERR_NONE) {
			rterror("rt_raster_gdal_rasterize: Unable to create OSR spatial reference using the provided srs: %s", srs);

			if (noband) {
				rtdealloc(_pixtype);
				rtdealloc(_init);
				rtdealloc(_nodata);
				rtdealloc(_hasnodata);
				rtdealloc(_value);
			}

			return NULL;
		}
	}

	/* convert WKB to OGR Geometry */
	ogrerr = OGR_G_CreateFromWkb((unsigned char *) wkb, src_sr, &src_geom, wkb_len);
	if (ogrerr != OGRERR_NONE) {
		rterror("rt_raster_gdal_rasterize: Unable to create OGR Geometry from WKB");

		if (noband) {
			rtdealloc(_pixtype);
			rtdealloc(_init);
			rtdealloc(_nodata);
			rtdealloc(_hasnodata);
			rtdealloc(_value);
		}

		OSRDestroySpatialReference(src_sr);
		/* OGRCleanupAll(); */

		return NULL;
	}

	/* get envelope */
	OGR_G_GetEnvelope(src_geom, &src_env);
	rt_util_from_ogr_envelope(src_env, &extent);

	RASTER_DEBUGF(3, "Suggested raster envelope: %f, %f, %f, %f",
		extent.MinX, extent.MinY, extent.MaxX, extent.MaxY);

	/* user-defined scale */
	if (
		(NULL != scale_x) &&
		(NULL != scale_y) &&
		(FLT_NEQ(*scale_x, 0.0)) &&
		(FLT_NEQ(*scale_y, 0.0))
	) {
		/* for now, force scale to be in left-right, top-down orientation */
		_scale[0] = fabs(*scale_x);
		_scale[1] = fabs(*scale_y);
	}
	/* user-defined width/height */
	else if (
		(NULL != width) &&
		(NULL != height) &&
		(FLT_NEQ(*width, 0.0)) &&
		(FLT_NEQ(*height, 0.0))
	) {
		_dim[0] = fabs(*width);
		_dim[1] = fabs(*height);

		if (FLT_NEQ(extent.MaxX, extent.MinX))
			_scale[0] = fabs((extent.MaxX - extent.MinX) / _dim[0]);
		else
			_scale[0] = 1.;

		if (FLT_NEQ(extent.MaxY, extent.MinY))
			_scale[1] = fabs((extent.MaxY - extent.MinY) / _dim[1]);
		else
			_scale[1] = 1.;
	}
	else {
		rterror("rt_raster_gdal_rasterize: Values must be provided for width and height or X and Y of scale");

		if (noband) {
			rtdealloc(_pixtype);
			rtdealloc(_init);
			rtdealloc(_nodata);
			rtdealloc(_hasnodata);
			rtdealloc(_value);
		}

		OGR_G_DestroyGeometry(src_geom);
		OSRDestroySpatialReference(src_sr);
		/* OGRCleanupAll(); */

		return NULL;
	}
	RASTER_DEBUGF(3, "scale (x, y) = %f, %f", _scale[0], -1 * _scale[1]);
	RASTER_DEBUGF(3, "dim (x, y) = %d, %d", _dim[0], _dim[1]);

	/* user-defined skew */
	if (NULL != skew_x) {
		_skew[0] = *skew_x;

		/*
			negative scale-x affects skew
			for now, force skew to be in left-right, top-down orientation
		*/
		if (
			NULL != scale_x &&
			*scale_x < 0.
		) {
			_skew[0] *= -1;
		}
	}
	if (NULL != skew_y) {
		_skew[1] = *skew_y;

		/*
			positive scale-y affects skew
			for now, force skew to be in left-right, top-down orientation
		*/
		if (
			NULL != scale_y &&
			*scale_y > 0.
		) {
			_skew[1] *= -1;
		}
	}

	/*
	 	if geometry is a point, a linestring or set of either and bounds not set,
		increase extent by a pixel to avoid missing points on border

		a whole pixel is used instead of half-pixel due to backward
		compatibility with GDAL 1.6, 1.7 and 1.8.  1.9+ works fine with half-pixel.
	*/
	wkbtype = wkbFlatten(OGR_G_GetGeometryType(src_geom));
	if ((
			(wkbtype == wkbPoint) ||
			(wkbtype == wkbMultiPoint) ||
			(wkbtype == wkbLineString) ||
			(wkbtype == wkbMultiLineString)
		) &&
		FLT_EQ(_dim[0], 0) &&
		FLT_EQ(_dim[1], 0)
	) {
		int result;
		LWPOLY *epoly = NULL;
		LWGEOM *lwgeom = NULL;
		GEOSGeometry *egeom = NULL;
		GEOSGeometry *geom = NULL;

		RASTER_DEBUG(3, "Testing geometry is properly contained by extent");

		/*
			see if geometry is properly contained by extent
			all parts of geometry lies within extent
		*/

		/* initialize GEOS */
		initGEOS(lwnotice, lwgeom_geos_error);

		/* convert envelope to geometry */
		RASTER_DEBUG(4, "Converting envelope to geometry");
		epoly = rt_util_envelope_to_lwpoly(extent);
		if (epoly == NULL) {
			rterror("rt_raster_gdal_rasterize: Unable to create envelope's geometry to test if geometry is properly contained by extent");

			if (noband) {
				rtdealloc(_pixtype);
				rtdealloc(_init);
				rtdealloc(_nodata);
				rtdealloc(_hasnodata);
				rtdealloc(_value);
			}

			OGR_G_DestroyGeometry(src_geom);
			OSRDestroySpatialReference(src_sr);
			/* OGRCleanupAll(); */

			return NULL;
		}

		egeom = (GEOSGeometry *) LWGEOM2GEOS(lwpoly_as_lwgeom(epoly));
		lwpoly_free(epoly);

		/* convert WKB to geometry */
		RASTER_DEBUG(4, "Converting WKB to geometry");
		lwgeom = lwgeom_from_wkb(wkb, wkb_len, LW_PARSER_CHECK_NONE);
		geom = (GEOSGeometry *) LWGEOM2GEOS(lwgeom);
		lwgeom_free(lwgeom);

		result = GEOSRelatePattern(egeom, geom, "T**FF*FF*");
		GEOSGeom_destroy(geom);
		GEOSGeom_destroy(egeom);

		if (result == 2) {
			rterror("rt_raster_gdal_rasterize: Unable to test if geometry is properly contained by extent for geometry within extent");

			if (noband) {
				rtdealloc(_pixtype);
				rtdealloc(_init);
				rtdealloc(_nodata);
				rtdealloc(_hasnodata);
				rtdealloc(_value);
			}

			OGR_G_DestroyGeometry(src_geom);
			OSRDestroySpatialReference(src_sr);
			/* OGRCleanupAll(); */

			return NULL;
		}

		/* geometry NOT properly contained by extent */
		if (!result) {

#if POSTGIS_GDAL_VERSION > 18

			/* check alignment flag: grid_xw */
			if (
				(NULL == ul_xw && NULL == ul_yw) &&
				(NULL != grid_xw && NULL != grid_xw) &&
				FLT_NEQ(*grid_xw, extent.MinX)
			) {
				// do nothing
				RASTER_DEBUG(3, "Skipping extent adjustment on X-axis due to upcoming alignment");
			}
			else {
				RASTER_DEBUG(3, "Adjusting extent for GDAL > 1.8 by half the scale on X-axis");
				extent.MinX -= (_scale[0] / 2.);
				extent.MaxX += (_scale[0] / 2.);
			}

			/* check alignment flag: grid_yw */
			if (
				(NULL == ul_xw && NULL == ul_yw) &&
				(NULL != grid_xw && NULL != grid_xw) &&
				FLT_NEQ(*grid_yw, extent.MaxY)
			) {
				// do nothing
				RASTER_DEBUG(3, "Skipping extent adjustment on Y-axis due to upcoming alignment");
			}
			else {
				RASTER_DEBUG(3, "Adjusting extent for GDAL > 1.8 by half the scale on Y-axis");
				extent.MinY -= (_scale[1] / 2.);
				extent.MaxY += (_scale[1] / 2.);
			}

#else

			/* check alignment flag: grid_xw */
			if (
				(NULL == ul_xw && NULL == ul_yw) &&
				(NULL != grid_xw && NULL != grid_xw) &&
				FLT_NEQ(*grid_xw, extent.MinX)
			) {
				// do nothing
				RASTER_DEBUG(3, "Skipping extent adjustment on X-axis due to upcoming alignment");
			}
			else {
				RASTER_DEBUG(3, "Adjusting extent for GDAL <= 1.8 by the scale on X-axis");
				extent.MinX -= _scale[0];
				extent.MaxX += _scale[0];
			}


			/* check alignment flag: grid_yw */
			if (
				(NULL == ul_xw && NULL == ul_yw) &&
				(NULL != grid_xw && NULL != grid_xw) &&
				FLT_NEQ(*grid_yw, extent.MaxY)
			) {
				// do nothing
				RASTER_DEBUG(3, "Skipping extent adjustment on Y-axis due to upcoming alignment");
			}
			else {
				RASTER_DEBUG(3, "Adjusting extent for GDAL <= 1.8 by the scale on Y-axis");
				extent.MinY -= _scale[1];
				extent.MaxY += _scale[1];
			}

#endif

		}

		RASTER_DEBUGF(3, "Adjusted extent: %f, %f, %f, %f",
			extent.MinX, extent.MinY, extent.MaxX, extent.MaxY);

		extent.UpperLeftX = extent.MinX;
		extent.UpperLeftY = extent.MaxY;
	}

	/* reprocess extent if skewed */
	if (
		FLT_NEQ(_skew[0], 0) ||
		FLT_NEQ(_skew[1], 0)
	) {
		rt_raster skewedrast;

		RASTER_DEBUG(3, "Computing skewed extent's envelope");

		skewedrast = rt_raster_compute_skewed_raster(
			extent,
			_skew,
			_scale,
			0.01
		);
		if (skewedrast == NULL) {
			rterror("rt_raster_gdal_rasterize: Could not compute skewed raster");

			if (noband) {
				rtdealloc(_pixtype);
				rtdealloc(_init);
				rtdealloc(_nodata);
				rtdealloc(_hasnodata);
				rtdealloc(_value);
			}

			OGR_G_DestroyGeometry(src_geom);
			OSRDestroySpatialReference(src_sr);
			/* OGRCleanupAll(); */

			return NULL;
		}

		_dim[0] = skewedrast->width;
		_dim[1] = skewedrast->height;

		extent.UpperLeftX = skewedrast->ipX;
		extent.UpperLeftY = skewedrast->ipY;

		rt_raster_destroy(skewedrast);
	}

	/* raster dimensions */
	if (!_dim[0])
		_dim[0] = (int) fmax((fabs(extent.MaxX - extent.MinX) + (_scale[0] / 2.)) / _scale[0], 1);
	if (!_dim[1])
		_dim[1] = (int) fmax((fabs(extent.MaxY - extent.MinY) + (_scale[1] / 2.)) / _scale[1], 1);

	/* temporary raster */
	rast = rt_raster_new(_dim[0], _dim[1]);
	if (rast == NULL) {
		rterror("rt_raster_gdal_rasterize: Out of memory allocating temporary raster");

		if (noband) {
			rtdealloc(_pixtype);
			rtdealloc(_init);
			rtdealloc(_nodata);
			rtdealloc(_hasnodata);
			rtdealloc(_value);
		}

		OGR_G_DestroyGeometry(src_geom);
		OSRDestroySpatialReference(src_sr);
		/* OGRCleanupAll(); */

		return NULL;
	}

	/* set raster's spatial attributes */
	rt_raster_set_offsets(rast, extent.UpperLeftX, extent.UpperLeftY);
	rt_raster_set_scale(rast, _scale[0], -1 * _scale[1]);
	rt_raster_set_skews(rast, _skew[0], _skew[1]);

	rt_raster_get_geotransform_matrix(rast, _gt);
	RASTER_DEBUGF(3, "Temp raster's geotransform: %f, %f, %f, %f, %f, %f",
		_gt[0], _gt[1], _gt[2], _gt[3], _gt[4], _gt[5]);
	RASTER_DEBUGF(3, "Temp raster's dimensions (width x height): %d x %d",
		_dim[0], _dim[1]);

	/* user-specified upper-left corner */
	if (
		NULL != ul_xw &&
		NULL != ul_yw
	) {
		ul_user = 1;

		RASTER_DEBUGF(4, "Using user-specified upper-left corner: %f, %f", *ul_xw, *ul_yw);

		/* set upper-left corner */
		rt_raster_set_offsets(rast, *ul_xw, *ul_yw);
		extent.UpperLeftX = *ul_xw;
		extent.UpperLeftY = *ul_yw;
	}
	else if (
		((NULL != ul_xw) && (NULL == ul_yw)) ||
		((NULL == ul_xw) && (NULL != ul_yw))
	) {
		rterror("rt_raster_gdal_rasterize: Both X and Y upper-left corner values must be provided");

		rt_raster_destroy(rast);

		if (noband) {
			rtdealloc(_pixtype);
			rtdealloc(_init);
			rtdealloc(_nodata);
			rtdealloc(_hasnodata);
			rtdealloc(_value);
		}

		OGR_G_DestroyGeometry(src_geom);
		OSRDestroySpatialReference(src_sr);
		/* OGRCleanupAll(); */

		return NULL;
	}

	/* alignment only considered if upper-left corner not provided */
	if (
		!ul_user && (
			(NULL != grid_xw) || (NULL != grid_yw)
		)
	) {

		if (
			((NULL != grid_xw) && (NULL == grid_yw)) ||
			((NULL == grid_xw) && (NULL != grid_yw))
		) {
			rterror("rt_raster_gdal_rasterize: Both X and Y alignment values must be provided");

			rt_raster_destroy(rast);

			if (noband) {
				rtdealloc(_pixtype);
				rtdealloc(_init);
				rtdealloc(_nodata);
				rtdealloc(_hasnodata);
				rtdealloc(_value);
			}

			OGR_G_DestroyGeometry(src_geom);
			OSRDestroySpatialReference(src_sr);
			/* OGRCleanupAll(); */

			return NULL;
		}

		RASTER_DEBUGF(4, "Aligning extent to user-specified grid: %f, %f", *grid_xw, *grid_yw);

		do {
			double _r[2] = {0};
			double _w[2] = {0};

			/* raster is already aligned */
			if (FLT_EQ(*grid_xw, extent.UpperLeftX) && FLT_EQ(*grid_yw, extent.UpperLeftY)) {
				RASTER_DEBUG(3, "Skipping raster alignment as it is already aligned to grid");
				break;
			}

			extent.UpperLeftX = rast->ipX;
			extent.UpperLeftY = rast->ipY;
			rt_raster_set_offsets(rast, *grid_xw, *grid_yw);

			/* process upper-left corner */
			if (!rt_raster_geopoint_to_cell(
				rast,
				extent.UpperLeftX, extent.UpperLeftY,
				&(_r[0]), &(_r[1]),
				NULL
			)) {
				rterror("rt_raster_gdal_rasterize: Unable to compute raster pixel for spatial coordinates");

				rt_raster_destroy(rast);

				if (noband) {
					rtdealloc(_pixtype);
					rtdealloc(_init);
					rtdealloc(_nodata);
					rtdealloc(_hasnodata);
					rtdealloc(_value);
				}

				OGR_G_DestroyGeometry(src_geom);
				OSRDestroySpatialReference(src_sr);
				/* OGRCleanupAll(); */

				return NULL;
			}

			if (!rt_raster_cell_to_geopoint(
				rast,
				_r[0], _r[1],
				&(_w[0]), &(_w[1]),
				NULL
			)) {
				rterror("rt_raster_gdal_rasterize: Unable to compute spatial coordinates for raster pixel");

				rt_raster_destroy(rast);

				if (noband) {
					rtdealloc(_pixtype);
					rtdealloc(_init);
					rtdealloc(_nodata);
					rtdealloc(_hasnodata);
					rtdealloc(_value);
				}

				OGR_G_DestroyGeometry(src_geom);
				OSRDestroySpatialReference(src_sr);
				/* OGRCleanupAll(); */

				return NULL;
			}

			/* shift occurred */
			if (FLT_NEQ(_w[0], extent.UpperLeftX)) {
				if (NULL == width)
					rast->width++;
				else if (NULL == scale_x) {
					double _c[2] = {0};

					rt_raster_set_offsets(rast, extent.UpperLeftX, extent.UpperLeftY);

					/* get upper-right corner */
					if (!rt_raster_cell_to_geopoint(
						rast,
						rast->width, 0,
						&(_c[0]), &(_c[1]),
						NULL
					)) {
						rterror("rt_raster_gdal_rasterize: Unable to compute spatial coordinates for raster pixel");

						rt_raster_destroy(rast);

						if (noband) {
							rtdealloc(_pixtype);
							rtdealloc(_init);
							rtdealloc(_nodata);
							rtdealloc(_hasnodata);
							rtdealloc(_value);
						}

						OGR_G_DestroyGeometry(src_geom);
						OSRDestroySpatialReference(src_sr);
						/* OGRCleanupAll(); */

						return NULL;
					}

					rast->scaleX = fabs((_c[0] - _w[0]) / ((double) rast->width));
				}
			}
			if (FLT_NEQ(_w[1], extent.UpperLeftY)) {
				if (NULL == height)
					rast->height++;
				else if (NULL == scale_y) {
					double _c[2] = {0};

					rt_raster_set_offsets(rast, extent.UpperLeftX, extent.UpperLeftY);

					/* get upper-right corner */
					if (!rt_raster_cell_to_geopoint(
						rast,
						0, rast->height,
						&(_c[0]), &(_c[1]),
						NULL
					)) {
						rterror("rt_raster_gdal_rasterize: Unable to compute spatial coordinates for raster pixel");

						rt_raster_destroy(rast);

						if (noband) {
							rtdealloc(_pixtype);
							rtdealloc(_init);
							rtdealloc(_nodata);
							rtdealloc(_hasnodata);
							rtdealloc(_value);
						}

						OGR_G_DestroyGeometry(src_geom);
						OSRDestroySpatialReference(src_sr);
						/* OGRCleanupAll(); */

						return NULL;
					}

					rast->scaleY = -1 * fabs((_c[1] - _w[1]) / ((double) rast->height));
				}
			}

			rt_raster_set_offsets(rast, _w[0], _w[1]);
		}
		while (0);
	}

	/*
		after this point, rt_envelope extent is no longer used
	*/

	/* get key attributes from rast */
	_dim[0] = rast->width;
	_dim[1] = rast->height;
	rt_raster_get_geotransform_matrix(rast, _gt);

	/* scale-x is negative or scale-y is positive */
	if ((
		(NULL != scale_x) && (*scale_x < 0.)
	) || (
		(NULL != scale_y) && (*scale_y > 0)
	)) {
		double _w[2] = {0};

		/* negative scale-x */
		if (
			(NULL != scale_x) &&
			(*scale_x < 0.)
		) {
			RASTER_DEBUG(3, "Processing negative scale-x");

			if (!rt_raster_cell_to_geopoint(
				rast,
				_dim[0], 0,
				&(_w[0]), &(_w[1]),
				NULL
			)) {
				rterror("rt_raster_gdal_rasterize: Unable to compute spatial coordinates for raster pixel");

				rt_raster_destroy(rast);

				if (noband) {
					rtdealloc(_pixtype);
					rtdealloc(_init);
					rtdealloc(_nodata);
					rtdealloc(_hasnodata);
					rtdealloc(_value);
				}

				OGR_G_DestroyGeometry(src_geom);
				OSRDestroySpatialReference(src_sr);
				/* OGRCleanupAll(); */

				return NULL;
			}

			_gt[0] = _w[0];
			_gt[1] = *scale_x;

			/* check for skew */
			if (NULL != skew_x && FLT_NEQ(*skew_x, 0))
				_gt[2] = *skew_x;
		}
		/* positive scale-y */
		if (
			(NULL != scale_y) &&
			(*scale_y > 0)
		) {
			RASTER_DEBUG(3, "Processing positive scale-y");

			if (!rt_raster_cell_to_geopoint(
				rast,
				0, _dim[1],
				&(_w[0]), &(_w[1]),
				NULL
			)) {
				rterror("rt_raster_gdal_rasterize: Unable to compute spatial coordinates for raster pixel");

				rt_raster_destroy(rast);

				if (noband) {
					rtdealloc(_pixtype);
					rtdealloc(_init);
					rtdealloc(_nodata);
					rtdealloc(_hasnodata);
					rtdealloc(_value);
				}

				OGR_G_DestroyGeometry(src_geom);
				OSRDestroySpatialReference(src_sr);
				/* OGRCleanupAll(); */

				return NULL;
			}

			_gt[3] = _w[1];
			_gt[5] = *scale_y;

			/* check for skew */
			if (NULL != skew_y && FLT_NEQ(*skew_y, 0))
				_gt[4] = *skew_y;
		}
	}

	rt_raster_destroy(rast);
	rast = NULL;

	RASTER_DEBUGF(3, "Applied geotransform: %f, %f, %f, %f, %f, %f",
		_gt[0], _gt[1], _gt[2], _gt[3], _gt[4], _gt[5]);
	RASTER_DEBUGF(3, "Raster dimensions (width x height): %d x %d",
		_dim[0], _dim[1]);

	/* load GDAL mem */
	if (!rt_util_gdal_driver_registered("MEM"))
		GDALRegister_MEM();
	_drv = GDALGetDriverByName("MEM");
	if (NULL == _drv) {
		rterror("rt_raster_gdal_rasterize: Unable to load the MEM GDAL driver");

		if (noband) {
			rtdealloc(_pixtype);
			rtdealloc(_init);
			rtdealloc(_nodata);
			rtdealloc(_hasnodata);
			rtdealloc(_value);
		}

		OGR_G_DestroyGeometry(src_geom);
		OSRDestroySpatialReference(src_sr);
		/* OGRCleanupAll(); */

		return NULL;
	}

	_ds = GDALCreate(_drv, "", _dim[0], _dim[1], 0, GDT_Byte, NULL);
	if (NULL == _ds) {
		rterror("rt_raster_gdal_rasterize: Could not create a GDALDataset to rasterize the geometry into");

		if (noband) {
			rtdealloc(_pixtype);
			rtdealloc(_init);
			rtdealloc(_nodata);
			rtdealloc(_hasnodata);
			rtdealloc(_value);
		}

		OGR_G_DestroyGeometry(src_geom);
		OSRDestroySpatialReference(src_sr);
		/* OGRCleanupAll(); */

		return NULL;
	}

	/* set geotransform */
	cplerr = GDALSetGeoTransform(_ds, _gt);
	if (cplerr != CE_None) {
		rterror("rt_raster_gdal_rasterize: Could not set geotransform on GDALDataset");

		if (noband) {
			rtdealloc(_pixtype);
			rtdealloc(_init);
			rtdealloc(_nodata);
			rtdealloc(_hasnodata);
			rtdealloc(_value);
		}

		OGR_G_DestroyGeometry(src_geom);
		OSRDestroySpatialReference(src_sr);
		/* OGRCleanupAll(); */

		GDALClose(_ds);

		return NULL;
	}

	/* set SRS */
	if (NULL != src_sr) {
		cplerr = GDALSetProjection(_ds, srs);
		if (cplerr != CE_None) {
			rterror("rt_raster_gdal_rasterize: Could not set projection on GDALDataset");

			if (noband) {
				rtdealloc(_pixtype);
				rtdealloc(_init);
				rtdealloc(_nodata);
				rtdealloc(_hasnodata);
				rtdealloc(_value);
			}

			OGR_G_DestroyGeometry(src_geom);
			OSRDestroySpatialReference(src_sr);
			/* OGRCleanupAll(); */

			GDALClose(_ds);

			return NULL;
		}
	}

	/* set bands */
	for (i = 0; i < num_bands; i++) {
		banderr = 0;

		do {
			/* add band */
			cplerr = GDALAddBand(_ds, rt_util_pixtype_to_gdal_datatype(_pixtype[i]), NULL);
			if (cplerr != CE_None) {
				rterror("rt_raster_gdal_rasterize: Unable to add band to GDALDataset");
				banderr = 1;
				break;
			}

			_band = GDALGetRasterBand(_ds, i + 1);
			if (NULL == _band) {
				rterror("rt_raster_gdal_rasterize: Unable to get band %d from GDALDataset", i + 1);
				banderr = 1;
				break;
			}

			/* nodata value */
			if (_hasnodata[i]) {
				RASTER_DEBUGF(4, "Setting NODATA value of band %d to %f", i, _nodata[i]);
				cplerr = GDALSetRasterNoDataValue(_band, _nodata[i]);
				if (cplerr != CE_None) {
					rterror("rt_raster_gdal_rasterize: Unable to set nodata value");
					banderr = 1;
					break;
				}
				RASTER_DEBUGF(4, "NODATA value set to %f", GDALGetRasterNoDataValue(_band, NULL));
			}

			/* initial value */
			cplerr = GDALFillRaster(_band, _init[i], 0);
			if (cplerr != CE_None) {
				rterror("rt_raster_gdal_rasterize: Unable to set initial value");
				banderr = 1;
				break;
			}
		}
		while (0);

		if (banderr) {
			if (noband) {
				rtdealloc(_pixtype);
				rtdealloc(_init);
				rtdealloc(_nodata);
				rtdealloc(_hasnodata);
				rtdealloc(_value);
			}

			OGR_G_DestroyGeometry(src_geom);
			OSRDestroySpatialReference(src_sr);
			/* OGRCleanupAll(); */

			GDALClose(_ds);

			return NULL;
		}
	}

	band_list = (int *) rtalloc(sizeof(int) * num_bands);
	for (i = 0; i < num_bands; i++) band_list[i] = i + 1;

	/* burn geometry */
	cplerr = GDALRasterizeGeometries(
		_ds,
		num_bands, band_list,
		1, &src_geom,
		NULL, NULL,
		_value,
		options,
		NULL, NULL
	);
	rtdealloc(band_list);
	if (cplerr != CE_None) {
		rterror("rt_raster_gdal_rasterize: Unable to rasterize geometry");

		if (noband) {
			rtdealloc(_pixtype);
			rtdealloc(_init);
			rtdealloc(_nodata);
			rtdealloc(_hasnodata);
			rtdealloc(_value);
		}

		OGR_G_DestroyGeometry(src_geom);
		OSRDestroySpatialReference(src_sr);
		/* OGRCleanupAll(); */

		GDALClose(_ds);

		return NULL;
	}

	/* convert gdal dataset to raster */
	GDALFlushCache(_ds);
	RASTER_DEBUG(3, "Converting GDAL dataset to raster");
	rast = rt_raster_from_gdal_dataset(_ds);

	if (noband) {
		rtdealloc(_pixtype);
		rtdealloc(_init);
		rtdealloc(_nodata);
		rtdealloc(_hasnodata);
		rtdealloc(_value);
	}

	OGR_G_DestroyGeometry(src_geom);
	OSRDestroySpatialReference(src_sr);
	/* OGRCleanupAll(); */

	GDALClose(_ds);

	if (NULL == rast) {
		rterror("rt_raster_gdal_rasterize: Unable to rasterize geometry");
		return NULL;
	}

	RASTER_DEBUG(3, "done");

	return rast;
}

static
int rt_raster_intersects_algorithm(
	rt_raster rast1, rt_raster rast2,
	rt_band band1, rt_band band2,
	int hasnodata1, int hasnodata2,
	double nodata1, double nodata2
) {
	int i;
	int byHeight = 1;
	uint32_t dimValue;

	uint32_t row;
	uint32_t rowoffset;
	uint32_t col;
	uint32_t coloffset;

	enum line_points {X1, Y1, X2, Y2};
	enum point {pX, pY};
	double line1[4] = {0.};
	double line2[4] = {0.};
	double P[2] = {0.};
	double Qw[2] = {0.};
	double Qr[2] = {0.};
	double gt1[6] = {0.};
	double gt2[6] = {0.};
	double igt1[6] = {0};
	double igt2[6] = {0};
	double d;
	double val1;
	int noval1;
	double val2;
	int noval2;
	uint32_t adjacent[8] = {0};

	double xscale;
	double yscale;

	uint16_t width1;
	uint16_t height1;
	uint16_t width2;
	uint16_t height2;

	width1 = rt_raster_get_width(rast1);
	height1 = rt_raster_get_height(rast1);
	width2 = rt_raster_get_width(rast2);
	height2 = rt_raster_get_height(rast2);

	/* sampling scale */
	xscale = fmin(rt_raster_get_x_scale(rast1), rt_raster_get_x_scale(rast2)) / 10.;
	yscale = fmin(rt_raster_get_y_scale(rast1), rt_raster_get_y_scale(rast2)) / 10.;

	/* see if skew made rast2's rows are parallel to rast1's cols */
	rt_raster_cell_to_geopoint(
		rast1,
		0, 0,
		&(line1[X1]), &(line1[Y1]),
		gt1
	);

	rt_raster_cell_to_geopoint(
		rast1,
		0, height1,
		&(line1[X2]), &(line1[Y2]),
		gt1
	);

	rt_raster_cell_to_geopoint(
		rast2,
		0, 0,
		&(line2[X1]), &(line2[Y1]),
		gt2
	);

	rt_raster_cell_to_geopoint(
		rast2,
		width2, 0,
		&(line2[X2]), &(line2[Y2]),
		gt2
	);

	/* parallel vertically */
	if (FLT_EQ(line1[X2] - line1[X1], 0.) && FLT_EQ(line2[X2] - line2[X1], 0.))
		byHeight = 0;
	/* parallel */
	else if (FLT_EQ(((line1[Y2] - line1[Y1]) / (line1[X2] - line1[X1])), ((line2[Y2] - line2[Y1]) / (line2[X2] - line2[X1]))))
		byHeight = 0;

	if (byHeight)
		dimValue = height2;
	else
		dimValue = width2;
	RASTER_DEBUGF(4, "byHeight: %d, dimValue: %d", byHeight, dimValue);

	/* 3 x 3 search */
	for (coloffset = 0; coloffset < 3; coloffset++) {
		for (rowoffset = 0; rowoffset < 3; rowoffset++) {
			/* smaller raster */
			for (col = coloffset; col <= width1; col += 3) {

				rt_raster_cell_to_geopoint(
					rast1,
					col, 0,
					&(line1[X1]), &(line1[Y1]),
					gt1
				);

				rt_raster_cell_to_geopoint(
					rast1,
					col, height1,
					&(line1[X2]), &(line1[Y2]),
					gt1
				);

				/* larger raster */
				for (row = rowoffset; row <= dimValue; row += 3) {

					if (byHeight) {
						rt_raster_cell_to_geopoint(
							rast2,
							0, row,
							&(line2[X1]), &(line2[Y1]),
							gt2
						);

						rt_raster_cell_to_geopoint(
							rast2,
							width2, row,
							&(line2[X2]), &(line2[Y2]),
							gt2
						);
					}
					else {
						rt_raster_cell_to_geopoint(
							rast2,
							row, 0,
							&(line2[X1]), &(line2[Y1]),
							gt2
						);

						rt_raster_cell_to_geopoint(
							rast2,
							row, height2,
							&(line2[X2]), &(line2[Y2]),
							gt2
						);
					}

					RASTER_DEBUGF(4, "(col, row) = (%d, %d)", col, row);
					RASTER_DEBUGF(4, "line1(x1, y1, x2, y2) = (%f, %f, %f, %f)",
						line1[X1], line1[Y1], line1[X2], line1[Y2]);
					RASTER_DEBUGF(4, "line2(x1, y1, x2, y2) = (%f, %f, %f, %f)",
						line2[X1], line2[Y1], line2[X2], line2[Y2]);

					/* intersection */
					/* http://en.wikipedia.org/wiki/Line-line_intersection */
					d = ((line1[X1] - line1[X2]) * (line2[Y1] - line2[Y2])) - ((line1[Y1] - line1[Y2]) * (line2[X1] - line2[X2]));
					/* no intersection */
					if (FLT_EQ(d, 0.)) {
						continue;
					}

					P[pX] = (((line1[X1] * line1[Y2]) - (line1[Y1] * line1[X2])) * (line2[X1] - line2[X2])) -
						((line1[X1] - line1[X2]) * ((line2[X1] * line2[Y2]) - (line2[Y1] * line2[X2])));
					P[pX] = P[pX] / d;

					P[pY] = (((line1[X1] * line1[Y2]) - (line1[Y1] * line1[X2])) * (line2[Y1] - line2[Y2])) -
						((line1[Y1] - line1[Y2]) * ((line2[X1] * line2[Y2]) - (line2[Y1] * line2[X2])));
					P[pY] = P[pY] / d;

					RASTER_DEBUGF(4, "P(x, y) = (%f, %f)", P[pX], P[pY]);

					/* intersection within bounds */
					if ((
							(FLT_EQ(P[pX], line1[X1]) || FLT_EQ(P[pX], line1[X2])) ||
								(P[pX] > fmin(line1[X1], line1[X2]) && (P[pX] < fmax(line1[X1], line1[X2])))
						) && (
							(FLT_EQ(P[pY], line1[Y1]) || FLT_EQ(P[pY], line1[Y2])) ||
								(P[pY] > fmin(line1[Y1], line1[Y2]) && (P[pY] < fmax(line1[Y1], line1[Y2])))
						) && (
							(FLT_EQ(P[pX], line2[X1]) || FLT_EQ(P[pX], line2[X2])) ||
								(P[pX] > fmin(line2[X1], line2[X2]) && (P[pX] < fmax(line2[X1], line2[X2])))
						) && (
							(FLT_EQ(P[pY], line2[Y1]) || FLT_EQ(P[pY], line2[Y2])) ||
								(P[pY] > fmin(line2[Y1], line2[Y2]) && (P[pY] < fmax(line2[Y1], line2[Y2])))
					)) {
						RASTER_DEBUG(4, "within bounds");

						for (i = 0; i < 8; i++) adjacent[i] = 0;

						/* test points around intersection */
						for (i = 0; i < 8; i++) {
							switch (i) {
								case 7:
									Qw[pX] = P[pX] - xscale;
									Qw[pY] = P[pY] + yscale;
									break;
								/* 270 degrees = 09:00 */
								case 6:
									Qw[pX] = P[pX] - xscale;
									Qw[pY] = P[pY];
									break;
								case 5:
									Qw[pX] = P[pX] - xscale;
									Qw[pY] = P[pY] - yscale;
									break;
								/* 180 degrees = 06:00 */
								case 4:
									Qw[pX] = P[pX];
									Qw[pY] = P[pY] - yscale;
									break;
								case 3:
									Qw[pX] = P[pX] + xscale;
									Qw[pY] = P[pY] - yscale;
									break;
								/* 90 degrees = 03:00 */
								case 2:
									Qw[pX] = P[pX] + xscale;
									Qw[pY] = P[pY];
									break;
								/* 45 degrees */
								case 1:
									Qw[pX] = P[pX] + xscale;
									Qw[pY] = P[pY] + yscale;
									break;
								/* 0 degrees = 00:00 */
								case 0:
									Qw[pX] = P[pX];
									Qw[pY] = P[pY] + yscale;
									break;
							}

							/* unable to convert point to cell */
							noval1 = 0;
							if (!rt_raster_geopoint_to_cell(
								rast1,
								Qw[pX], Qw[pY],
								&(Qr[pX]), &(Qr[pY]),
								igt1
							)) {
								noval1 = 1;
							}
							/* cell is outside bounds of grid */
							else if (
								(Qr[pX] < 0 || Qr[pX] > width1 || FLT_EQ(Qr[pX], width1)) ||
								(Qr[pY] < 0 || Qr[pY] > height1 || FLT_EQ(Qr[pY], height1))
							) {
								noval1 = 1;
							}
							else if (hasnodata1 == FALSE)
								val1 = 1;
							/* unable to get value at cell */
							else if (rt_band_get_pixel(band1, Qr[pX], Qr[pY], &val1) < 0)
								noval1 = 1;

							/* unable to convert point to cell */
							noval2 = 0;
							if (!rt_raster_geopoint_to_cell(
								rast2,
								Qw[pX], Qw[pY],
								&(Qr[pX]), &(Qr[pY]),
								igt2
							)) {
								noval2 = 1;
							}
							/* cell is outside bounds of grid */
							else if (
								(Qr[pX] < 0 || Qr[pX] > width2 || FLT_EQ(Qr[pX], width2)) ||
								(Qr[pY] < 0 || Qr[pY] > height2 || FLT_EQ(Qr[pY], height2))
							) {
								noval2 = 1;
							}
							else if (hasnodata2 == FALSE)
								val2 = 1;
							/* unable to get value at cell */
							else if (rt_band_get_pixel(band2, Qr[pX], Qr[pY], &val2) < 0)
								noval2 = 1;

							if (!noval1) {
								RASTER_DEBUGF(4, "val1 = %f", val1);
							}
							if (!noval2) {
								RASTER_DEBUGF(4, "val2 = %f", val2);
							}

							/* pixels touch */
							if (!noval1 && (
								(hasnodata1 == FALSE) || (
									(hasnodata1 != FALSE) &&
									FLT_NEQ(val1, nodata1)
								)
							)) {
								adjacent[i]++;
							}
							if (!noval2 && (
								(hasnodata2 == FALSE) || (
									(hasnodata2 != FALSE) &&
									FLT_NEQ(val2, nodata2)
								)
							)) {
								adjacent[i] += 3;
							}

							/* two pixel values not present */
							if (noval1 || noval2) {
								RASTER_DEBUGF(4, "noval1 = %d, noval2 = %d", noval1, noval2);
								continue;
							}

							/* pixels valid, so intersect */
							if ((
									(hasnodata1 == FALSE) || (
										(hasnodata1 != FALSE) &&
										FLT_NEQ(val1, nodata1)
									)
								) && (
									(hasnodata2 == FALSE) || (
										(hasnodata2 != FALSE) &&
										FLT_NEQ(val2, nodata2)
									)
							)) {
								RASTER_DEBUG(3, "The two rasters do intersect");

								return 1;
							}
						}

						/* pixels touch */
						for (i = 0; i < 4; i++) {
							RASTER_DEBUGF(4, "adjacent[%d] = %d, adjacent[%d] = %d"
								, i, adjacent[i], i + 4, adjacent[i + 4]);
							if (adjacent[i] == 0) continue;

							if (adjacent[i] + adjacent[i + 4] == 4) {
								RASTER_DEBUG(3, "The two rasters touch");

								return 1;
							}
						}
					}
					else {
						RASTER_DEBUG(4, "outside of bounds");
					}
				}
			}
		}
	}

	return 0;
}

/**
 * Return zero if error occurred in function.
 * Parameter intersects returns non-zero if two rasters intersect
 *
 * @param rast1 : the first raster whose band will be tested
 * @param nband1 : the 0-based band of raster rast1 to use
 *   if value is less than zero, bands are ignored.
 *   if nband1 gte zero, nband2 must be gte zero
 * @param rast2 : the second raster whose band will be tested
 * @param nband2 : the 0-based band of raster rast2 to use
 *   if value is less than zero, bands are ignored
 *   if nband2 gte zero, nband1 must be gte zero
 * @param intersects : non-zero value if the two rasters' bands intersects
 *
 * @return if zero, an error occurred in function
 */
int
rt_raster_intersects(
	rt_raster rast1, int nband1,
	rt_raster rast2, int nband2,
	int *intersects
) {
	int i;
	int j;
	int within = 0;

	LWPOLY *hull[2] = {NULL};
	GEOSGeometry *ghull[2] = {NULL};

	uint16_t width1;
	uint16_t height1;
	uint16_t width2;
	uint16_t height2;
	double area1;
	double area2;
	double pixarea1;
	double pixarea2;
	rt_raster rastS = NULL;
	rt_raster rastL = NULL;
	uint16_t *widthS = NULL;
	uint16_t *heightS = NULL;
	uint16_t *widthL = NULL;
	uint16_t *heightL = NULL;
	int nbandS;
	int nbandL;
	rt_band bandS = NULL;
	rt_band bandL = NULL;
	int hasnodataS = FALSE;
	int hasnodataL = FALSE;
	double nodataS = 0;
	double nodataL = 0;
	double gtS[6] = {0};
	double igtL[6] = {0};

	uint32_t row;
	uint32_t rowoffset;
	uint32_t col;
	uint32_t coloffset;

	enum line_points {X1, Y1, X2, Y2};
	enum point {pX, pY};
	double lineS[4];
	double Qr[2];
	double valS;
	double valL;

	RASTER_DEBUG(3, "Starting");

	assert(NULL != rast1);
	assert(NULL != rast2);

	if (nband1 < 0 && nband2 < 0) {
		nband1 = -1;
		nband2 = -1;
	}
	else {
		assert(nband1 >= 0 && nband1 < rt_raster_get_num_bands(rast1));
		assert(nband2 >= 0 && nband2 < rt_raster_get_num_bands(rast2));
	}

	/* same srid */
	if (rt_raster_get_srid(rast1) != rt_raster_get_srid(rast2)) {
		rterror("rt_raster_intersects: The two rasters provided have different SRIDs");
		*intersects = 0;
		return 0;
	}

	/* raster extents need to intersect */
	do {
		int rtn;

		initGEOS(lwnotice, lwgeom_geos_error);

		rtn = 1;
		for (i = 0; i < 2; i++) {
			hull[i] = rt_raster_get_convex_hull(i < 1 ? rast1 : rast2);
			if (NULL == hull[i]) {
				for (j = 0; j < i; j++) {
					GEOSGeom_destroy(ghull[j]);
					lwpoly_free(hull[j]);
				}
				rtn = 0;
				break;
			}
			ghull[i] = (GEOSGeometry *) LWGEOM2GEOS(lwpoly_as_lwgeom(hull[i]));
			if (NULL == ghull[i]) {
				for (j = 0; j < i; j++) {
					GEOSGeom_destroy(ghull[j]);
					lwpoly_free(hull[j]);
				}
				lwpoly_free(hull[i]);
				rtn = 0;
				break;
			}
		}
		if (!rtn) break;

		/* test to see if raster within the other */
		within = 0;
		if (GEOSWithin(ghull[0], ghull[1]) == 1)
			within = -1;
		else if (GEOSWithin(ghull[1], ghull[0]) == 1)
			within = 1;

		if (within != 0)
			rtn = 1;
		else
			rtn = GEOSIntersects(ghull[0], ghull[1]);

		for (i = 0; i < 2; i++) {
			GEOSGeom_destroy(ghull[i]);
			lwpoly_free(hull[i]);
		}

		if (rtn != 2) {
			RASTER_DEBUGF(4, "convex hulls of rasters do %sintersect", rtn != 1 ? "NOT " : "");
			if (rtn != 1) {
				*intersects = 0;
				return 1;
			}
			/* band isn't specified */
			else if (nband1 < 0) {
				*intersects = 1;
				return 1;
			}
		}
	}
	while (0);

	/* smaller raster by area or width */
	width1 = rt_raster_get_width(rast1);
	height1 = rt_raster_get_height(rast1);
	width2 = rt_raster_get_width(rast2);
	height2 = rt_raster_get_height(rast2);
	pixarea1 = fabs(rt_raster_get_x_scale(rast1) * rt_raster_get_y_scale(rast1));
	pixarea2 = fabs(rt_raster_get_x_scale(rast2) * rt_raster_get_y_scale(rast2));
	area1 = fabs(width1 * height1 * pixarea1);
	area2 = fabs(width2 * height2 * pixarea2);
	RASTER_DEBUGF(4, "pixarea1, pixarea2, area1, area2 = %f, %f, %f, %f",
		pixarea1, pixarea2, area1, area2);
	if (
		(within <= 0) ||
		(area1 < area2) ||
		FLT_EQ(area1, area2) ||
		(area1 < pixarea2) || /* area of rast1 smaller than pixel area of rast2 */
		FLT_EQ(area1, pixarea2)
	) {
		rastS = rast1;
		nbandS = nband1;
		widthS = &width1;
		heightS = &height1;

		rastL = rast2;
		nbandL = nband2;
		widthL = &width2;
		heightL = &height2;
	}
	else {
		rastS = rast2;
		nbandS = nband2;
		widthS = &width2;
		heightS = &height2;

		rastL = rast1;
		nbandL = nband1;
		widthL = &width1;
		heightL = &height1;
	}

	/* no band to use, set band to zero */
	if (nband1 < 0) {
		nbandS = 0;
		nbandL = 0;
	}

	RASTER_DEBUGF(4, "rast1 @ %p", rast1);
	RASTER_DEBUGF(4, "rast2 @ %p", rast2);
	RASTER_DEBUGF(4, "rastS @ %p", rastS);
	RASTER_DEBUGF(4, "rastL @ %p", rastL);

	/* load band of smaller raster */
	bandS = rt_raster_get_band(rastS, nbandS);
	if (NULL == bandS) {
		rterror("rt_raster_intersects: Unable to get band %d of the first raster", nbandS);
		*intersects = 0;
		return 0;
	}
	if (bandS->offline) {
		rterror("rt_raster_intersects not implemented yet for OFFDB bands");
		*intersects = 0;
		return 0;
	}

	hasnodataS = rt_band_get_hasnodata_flag(bandS);
	if (hasnodataS != FALSE)
		nodataS = rt_band_get_nodata(bandS);

	/* load band of larger raster */
	bandL = rt_raster_get_band(rastL, nbandL);
	if (NULL == bandL) {
		rterror("rt_raster_intersects: Unable to get band %d of the first raster", nbandL);
		*intersects = 0;
		return 0;
	}
	if (bandL->offline) {
		rterror("rt_raster_intersects not implemented yet for OFFDB bands");
		*intersects = 0;
		return 0;
	}

	hasnodataL = rt_band_get_hasnodata_flag(bandL);
	if (hasnodataL != FALSE)
		nodataL = rt_band_get_nodata(bandL);

	/* no band to use, ignore nodata */
	if (nband1 < 0) {
		hasnodataS = FALSE;
		hasnodataL = FALSE;
	}

	/* special case where a raster can fit inside another raster's pixel */
	if (within != 0 && ((pixarea1 > area2) || (pixarea2 > area1))) {
		RASTER_DEBUG(4, "Using special case of raster fitting into another raster's pixel");
		/* 3 x 3 search */
		for (coloffset = 0; coloffset < 3; coloffset++) {
			for (rowoffset = 0; rowoffset < 3; rowoffset++) {
				for (col = coloffset; col < *widthS; col += 3) {
					for (row = rowoffset; row < *heightS; row += 3) {
						if (hasnodataS == FALSE)
							valS = 1;
						else if (rt_band_get_pixel(bandS, col, row, &valS) < 0)
							continue;

						if ((hasnodataS == FALSE) || (
							(hasnodataS != FALSE) &&
							FLT_NEQ(valS, nodataS)
						)) {
							rt_raster_cell_to_geopoint(
								rastS,
								col, row,
								&(lineS[X1]), &(lineS[Y1]),
								gtS
							);

							if (!rt_raster_geopoint_to_cell(
								rastL,
								lineS[X1], lineS[Y1],
								&(Qr[pX]), &(Qr[pY]),
								igtL
							)) {
								continue;
							}

							if (
								(Qr[pX] < 0 || Qr[pX] > *widthL || FLT_EQ(Qr[pX], *widthL)) ||
								(Qr[pY] < 0 || Qr[pY] > *heightL || FLT_EQ(Qr[pY], *heightL))
							) {
								continue;
							}

							if (hasnodataS == FALSE)
								valL = 1;
							else if (rt_band_get_pixel(bandL, Qr[pX], Qr[pY], &valL) < 0)
								continue;

							if ((hasnodataL == FALSE) || (
								(hasnodataL != FALSE) &&
								FLT_NEQ(valL, nodataL)
							)) {
								RASTER_DEBUG(3, "The two rasters do intersect");
								*intersects = 1;
								return 1;
							}
						}
					}
				}
			}
		}
	}

	*intersects = rt_raster_intersects_algorithm(
		rastS, rastL,
		bandS, bandL,
		hasnodataS, hasnodataL,
		nodataS, nodataL
	);

	if (*intersects) return 1;

	*intersects = rt_raster_intersects_algorithm(
		rastL, rastS,
		bandL, bandS,
		hasnodataL, hasnodataS,
		nodataL, nodataS
	);

	if (*intersects) return 1;

	RASTER_DEBUG(3, "The two rasters do not intersect");

	*intersects = 0;
	return 1;
}

/*
 * Return zero if error occurred in function.
 * Paramter aligned returns non-zero if two rasters are aligned
 *
 * @param rast1 : the first raster for alignment test
 * @param rast2 : the second raster for alignment test
 * @param aligned : non-zero value if the two rasters are aligned
 *
 * @return if zero, an error occurred in function
 */
int
rt_raster_same_alignment(
	rt_raster rast1,
	rt_raster rast2,
	int *aligned
) {
	double xr;
	double yr;
	double xw;
	double yw;
	int err = 0;

	assert(NULL != rast1);
	assert(NULL != rast2);

	err = 0;
	/* same srid */
	if (rt_raster_get_srid(rast1) != rt_raster_get_srid(rast2)) {
		RASTER_DEBUG(3, "The two rasters provided have different SRIDs");
		err = 1;
	}
	/* scales must match */
	else if (FLT_NEQ(fabs(rast1->scaleX), fabs(rast2->scaleX))) {
		RASTER_DEBUG(3, "The two raster provided have different scales on the X axis");
		err = 1;
	}
	else if (FLT_NEQ(fabs(rast1->scaleY), fabs(rast2->scaleY))) {
		RASTER_DEBUG(3, "The two raster provided have different scales on the Y axis");
		err = 1;
	}
	/* skews must match */
	else if (FLT_NEQ(rast1->skewX, rast2->skewX)) {
		RASTER_DEBUG(3, "The two raster provided have different skews on the X axis");
		err = 1;
	}
	else if (FLT_NEQ(rast1->skewY, rast2->skewY)) {
		RASTER_DEBUG(3, "The two raster provided have different skews on the Y axis");
		err = 1;
	}

	if (err) {
		*aligned = 0;
		return 1;
	}

	/* raster coordinates in context of second raster of first raster's upper-left corner */
	if (rt_raster_geopoint_to_cell(
			rast2,
			rast1->ipX, rast1->ipY,
			&xr, &yr,
			NULL
	) == 0) {
		rterror("rt_raster_same_alignment: Unable to get raster coordinates of second raster from first raster's spatial coordinates");
		*aligned = 0;
		return 0;
	}

	/* spatial coordinates of raster coordinates from above */
	if (rt_raster_cell_to_geopoint(
		rast2,
		xr, yr,
		&xw, &yw,
		NULL
	) == 0) {
		rterror("rt_raster_same_alignment: Unable to get spatial coordinates of second raster from raster coordinates");
		*aligned = 0;
		return 0;
	}

	RASTER_DEBUGF(4, "rast1(ipX, ipxY) = (%f, %f)", rast1->ipX, rast1->ipY);
	RASTER_DEBUGF(4, "rast2(xr, yr) = (%f, %f)", xr, yr);
	RASTER_DEBUGF(4, "rast2(xw, yw) = (%f, %f)", xw, yw);

	/* spatial coordinates are identical to that of first raster's upper-left corner */
	if (FLT_EQ(xw, rast1->ipX) && FLT_EQ(yw, rast1->ipY)) {
		RASTER_DEBUG(3, "The two rasters are aligned");
		*aligned = 1;
		return 1;
	}

	/* no alignment */
	RASTER_DEBUG(3, "The two rasters are NOT aligned");
	*aligned = 0;
	return 1;
}

/*
 * Return raster of computed extent specified extenttype applied
 * on two input rasters.  The raster returned should be freed by
 * the caller
 *
 * @param rast1 : the first raster
 * @param rast2 : the second raster
 * @param extenttype : type of extent for the output raster
 * @param err : if 0, error occurred
 * @param offset : 4-element array indicating the X,Y offsets
 * for each raster. 0,1 for rast1 X,Y. 2,3 for rast2 X,Y.
 *
 * @return raster object if success, NULL otherwise
 */
rt_raster
rt_raster_from_two_rasters(
	rt_raster rast1, rt_raster rast2,
	rt_extenttype extenttype,
	int *err, double *offset
) {
	int i;

	rt_raster _rast[2] = {rast1, rast2};
	double _offset[2][4] = {{0.}};
	uint16_t _dim[2][2] = {{0}};

	rt_raster raster = NULL;
	int aligned = 0;
	int dim[2] = {0};
	double gt[6] = {0.};

	assert(NULL != rast1);
	assert(NULL != rast2);

	/* rasters must have same srid */
	if (rt_raster_get_srid(rast1) != rt_raster_get_srid(rast2)) {
		rterror("rt_raster_from_two_rasters: The two rasters provided do not have the same SRID");
		*err = 0;
		return NULL;
	}

	/* rasters must be aligned */
	if (!rt_raster_same_alignment(rast1, rast2, &aligned)) {
		rterror("rt_raster_from_two_rasters: Unable to test for alignment on the two rasters");
		*err = 0;
		return NULL;
	}
	if (!aligned) {
		rterror("rt_raster_from_two_rasters: The two rasters provided do not have the same alignment");
		*err = 0;
		return NULL;
	}

	/* dimensions */
	_dim[0][0] = rast1->width;
	_dim[0][1] = rast1->height;
	_dim[1][0] = rast2->width;
	_dim[1][1] = rast2->height;

	/* get raster offsets */
	if (!rt_raster_geopoint_to_cell(
		_rast[1],
		_rast[0]->ipX, _rast[0]->ipY,
		&(_offset[1][0]), &(_offset[1][1]),
		NULL
	)) {
		rterror("rt_raster_from_two_rasters: Unable to compute offsets of the second raster relative to the first raster");
		*err = 0;
		return NULL;
	}
	_offset[1][0] = -1 * _offset[1][0];
	_offset[1][1] = -1 * _offset[1][1];
	_offset[1][2] = _offset[1][0] + _dim[1][0] - 1;
	_offset[1][3] = _offset[1][1] + _dim[1][1] - 1;

	i = -1;
	switch (extenttype) {
		case ET_FIRST:
			i = 0;
			_offset[0][0] = 0.;
			_offset[0][1] = 0.;
		case ET_SECOND:
			if (i < 0) {
				i = 1;
				_offset[0][0] = -1 * _offset[1][0];
				_offset[0][1] = -1 * _offset[1][1];
				_offset[1][0] = 0.;
				_offset[1][1] = 0.;
			}

			dim[0] = _dim[i][0];
			dim[1] = _dim[i][1];
			raster = rt_raster_new(
				dim[0],
				dim[1]
			);
			if (raster == NULL) {
				rterror("rt_raster_from_two_rasters: Unable to create output raster");
				*err = 0;
				return NULL;
			}
			rt_raster_set_srid(raster, _rast[i]->srid);
			rt_raster_get_geotransform_matrix(_rast[i], gt);
			rt_raster_set_geotransform_matrix(raster, gt);
			break;
		case ET_UNION: {
			double off[4] = {0};

			rt_raster_get_geotransform_matrix(_rast[0], gt);
			RASTER_DEBUGF(4, "gt = (%f, %f, %f, %f, %f, %f)",
				gt[0],
				gt[1],
				gt[2],
				gt[3],
				gt[4],
				gt[5]
			);

			/* new raster upper left offset */
			off[0] = 0;
			if (_offset[1][0] < 0)
				off[0] = _offset[1][0];
			off[1] = 0;
			if (_offset[1][1] < 0)
				off[1] = _offset[1][1];

			/* new raster lower right offset */
			off[2] = _dim[0][0] - 1;
			if ((int) _offset[1][2] >= _dim[0][0])
				off[2] = _offset[1][2];
			off[3] = _dim[0][1] - 1;
			if ((int) _offset[1][3] >= _dim[0][1])
				off[3] = _offset[1][3];

			/* upper left corner */
			if (!rt_raster_cell_to_geopoint(
				_rast[0],
				off[0], off[1],
				&(gt[0]), &(gt[3]),
				NULL
			)) {
				rterror("rt_raster_from_two_rasters: Unable to get spatial coordinates of upper-left pixel of output raster");
				*err = 0;
				return NULL;
			}

			dim[0] = off[2] - off[0] + 1;
			dim[1] = off[3] - off[1] + 1;
			RASTER_DEBUGF(4, "off = (%f, %f, %f, %f)",
				off[0],
				off[1],
				off[2],
				off[3]
			);
			RASTER_DEBUGF(4, "dim = (%d, %d)", dim[0], dim[1]);

			raster = rt_raster_new(
				dim[0],
				dim[1]
			);
			if (raster == NULL) {
				rterror("rt_raster_from_two_rasters: Unable to create output raster");
				*err = 0;
				return NULL;
			}
			rt_raster_set_srid(raster, _rast[0]->srid);
			rt_raster_set_geotransform_matrix(raster, gt);
			RASTER_DEBUGF(4, "gt = (%f, %f, %f, %f, %f, %f)",
				gt[0],
				gt[1],
				gt[2],
				gt[3],
				gt[4],
				gt[5]
			);

			/* get offsets */
			if (!rt_raster_geopoint_to_cell(
				_rast[0],
				gt[0], gt[3],
				&(_offset[0][0]), &(_offset[0][1]),
				NULL
			)) {
				rterror("rt_raster_from_two_rasters: Unable to get offsets of the FIRST raster relative to the output raster");
				rt_raster_destroy(raster);
				*err = 0;
				return NULL;
			}
			_offset[0][0] *= -1;
			_offset[0][1] *= -1;

			if (!rt_raster_geopoint_to_cell(
				_rast[1],
				gt[0], gt[3],
				&(_offset[1][0]), &(_offset[1][1]),
				NULL
			)) {
				rterror("rt_raster_from_two_rasters: Unable to get offsets of the SECOND raster relative to the output raster");
				rt_raster_destroy(raster);
				*err = 0;
				return NULL;
			}
			_offset[1][0] *= -1;
			_offset[1][1] *= -1;
			break;
		}
		case ET_INTERSECTION: {
			double off[4] = {0};

			/* no intersection */
			if (
				(_offset[1][2] < 0 || _offset[1][0] > (_dim[0][0] - 1)) ||
				(_offset[1][3] < 0 || _offset[1][1] > (_dim[0][1] - 1))
			) {
				RASTER_DEBUG(3, "The two rasters provided have no intersection.  Returning no band raster");

				raster = rt_raster_new(0, 0);
				if (raster == NULL) {
					rterror("rt_raster_from_two_rasters: Unable to create output raster");
					*err = 0;
					return NULL;
				}
				rt_raster_set_srid(raster, _rast[0]->srid);
				rt_raster_set_scale(raster, 0, 0);

				/* set offsets if provided */
				if (NULL != offset) {
					for (i = 0; i < 4; i++)
						offset[i] = _offset[i / 2][i % 2];
				}

				*err = 1;
				return raster;
			}

			if (_offset[1][0] > 0)
				off[0] = _offset[1][0];
			if (_offset[1][1] > 0)
				off[1] = _offset[1][1];

			off[2] = _dim[0][0] - 1;
			if (_offset[1][2] < _dim[0][0])
				off[2] = _offset[1][2];
			off[3] = _dim[0][1] - 1;
			if (_offset[1][3] < _dim[0][1])
				off[3] = _offset[1][3];

			dim[0] = off[2] - off[0] + 1;
			dim[1] = off[3] - off[1] + 1;
			raster = rt_raster_new(
				dim[0],
				dim[1]
			);
			if (raster == NULL) {
				rterror("rt_raster_from_two_rasters: Unable to create output raster");
				*err = 0;
				return NULL;
			}
			rt_raster_set_srid(raster, _rast[0]->srid);

			/* get upper-left corner */
			rt_raster_get_geotransform_matrix(_rast[0], gt);
			if (!rt_raster_cell_to_geopoint(
				_rast[0],
				off[0], off[1],
				&(gt[0]), &(gt[3]),
				gt
			)) {
				rterror("rt_raster_from_two_rasters: Unable to get spatial coordinates of upper-left pixel of output raster");
				rt_raster_destroy(raster);
				*err = 0;
				return NULL;
			}

			rt_raster_set_geotransform_matrix(raster, gt);

			/* get offsets */
			if (!rt_raster_geopoint_to_cell(
				_rast[0],
				gt[0], gt[3],
				&(_offset[0][0]), &(_offset[0][1]),
				NULL
			)) {
				rterror("rt_raster_from_two_rasters: Unable to get pixel coordinates to compute the offsets of the FIRST raster relative to the output raster");
				rt_raster_destroy(raster);
				*err = 0;
				return NULL;
			}
			_offset[0][0] *= -1;
			_offset[0][1] *= -1;

			if (!rt_raster_geopoint_to_cell(
				_rast[1],
				gt[0], gt[3],
				&(_offset[1][0]), &(_offset[1][1]),
				NULL
			)) {
				rterror("rt_raster_from_two_rasters: Unable to get pixel coordinates to compute the offsets of the SECOND raster relative to the output raster");
				rt_raster_destroy(raster);
				*err = 0;
				return NULL;
			}
			_offset[1][0] *= -1;
			_offset[1][1] *= -1;
			break;
		}
	}

	/* set offsets if provided */
	if (NULL != offset) {
		for (i = 0; i < 4; i++)
			offset[i] = _offset[i / 2][i % 2];
	}

	*err = 1;
	return raster;
}


LWPOLY*
rt_raster_pixel_as_polygon(rt_raster rast, int x, int y)
{
    double scale_x, scale_y;
    double skew_x, skew_y;
    double ul_x, ul_y;
    int srid;
    POINTARRAY **points;
    POINT4D p, p0;
    LWPOLY *poly;

    scale_x = rt_raster_get_x_scale(rast);
    scale_y = rt_raster_get_y_scale(rast);
    skew_x = rt_raster_get_x_skew(rast);
    skew_y = rt_raster_get_y_skew(rast);
    ul_x = rt_raster_get_x_offset(rast);
    ul_y = rt_raster_get_y_offset(rast);
    srid = rt_raster_get_srid(rast);

    points = rtalloc(sizeof(POINTARRAY *)*1);
    points[0] = ptarray_construct(0, 0, 5);

    p0.x = scale_x * x + skew_x * y + ul_x;
    p0.y = scale_y * y + skew_y * x + ul_y;
    ptarray_set_point4d(points[0], 0, &p0);

    p.x = p0.x + scale_x;
    p.y = p0.y + skew_y;
    ptarray_set_point4d(points[0], 1, &p);

    p.x = p0.x + scale_x + skew_x;
    p.y = p0.y + scale_y + skew_y;
    ptarray_set_point4d(points[0], 2, &p);

    p.x = p0.x + skew_x;
    p.y = p0.y + scale_y;
    ptarray_set_point4d(points[0], 3, &p);

    /* close it */
    ptarray_set_point4d(points[0], 4, &p0);

    poly = lwpoly_construct(srid, NULL, 1, points);

    return poly;
}