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pngwrite.c
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pngwrite.c
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/* pngwrite.c - general routines to write a PNG file
*
* Last changed in libpng 1.4.8 [July 7, 2011]
* Copyright (c) 1998-2011 Glenn Randers-Pehrson
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
* (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*/
/* Get internal access to png.h */
#define PNG_NO_PEDANTIC_WARNINGS
#include "png.h"
#ifdef PNG_WRITE_SUPPORTED
#include "pngpriv.h"
/* Writes all the PNG information. This is the suggested way to use the
* library. If you have a new chunk to add, make a function to write it,
* and put it in the correct location here. If you want the chunk written
* after the image data, put it in png_write_end(). I strongly encourage
* you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing
* the chunk, as that will keep the code from breaking if you want to just
* write a plain PNG file. If you have long comments, I suggest writing
* them in png_write_end(), and compressing them.
*/
void PNGAPI
png_write_info_before_PLTE(png_structp png_ptr, png_infop info_ptr)
{
png_debug(1, "in png_write_info_before_PLTE");
if (png_ptr == NULL || info_ptr == NULL)
return;
if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
{
/* Write PNG signature */
png_write_sig(png_ptr);
#ifdef PNG_MNG_FEATURES_SUPPORTED
if ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) && \
(png_ptr->mng_features_permitted))
{
png_warning(png_ptr, "MNG features are not allowed in a PNG datastream");
png_ptr->mng_features_permitted = 0;
}
#endif
/* Write IHDR information. */
png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height,
info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type,
info_ptr->filter_type,
#ifdef PNG_WRITE_INTERLACING_SUPPORTED
info_ptr->interlace_type);
#else
0);
#endif
/* The rest of these check to see if the valid field has the appropriate
* flag set, and if it does, writes the chunk.
*/
#if defined(PNG_WRITE_APNG_SUPPORTED)
if (info_ptr->valid & PNG_INFO_acTL)
png_write_acTL(png_ptr, info_ptr->num_frames, info_ptr->num_plays);
#endif
#ifdef PNG_WRITE_gAMA_SUPPORTED
if (info_ptr->valid & PNG_INFO_gAMA)
{
# ifdef PNG_FLOATING_POINT_SUPPORTED
png_write_gAMA(png_ptr, info_ptr->gamma);
#else
#ifdef PNG_FIXED_POINT_SUPPORTED
png_write_gAMA_fixed(png_ptr, info_ptr->int_gamma);
# endif
#endif
}
#endif
#ifdef PNG_WRITE_sRGB_SUPPORTED
if (info_ptr->valid & PNG_INFO_sRGB)
png_write_sRGB(png_ptr, (int)info_ptr->srgb_intent);
#endif
#ifdef PNG_WRITE_iCCP_SUPPORTED
if (info_ptr->valid & PNG_INFO_iCCP)
png_write_iCCP(png_ptr, info_ptr->iccp_name, PNG_COMPRESSION_TYPE_BASE,
info_ptr->iccp_profile, (int)info_ptr->iccp_proflen);
#endif
#ifdef PNG_WRITE_sBIT_SUPPORTED
if (info_ptr->valid & PNG_INFO_sBIT)
png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type);
#endif
#ifdef PNG_WRITE_cHRM_SUPPORTED
if (info_ptr->valid & PNG_INFO_cHRM)
{
#ifdef PNG_FLOATING_POINT_SUPPORTED
png_write_cHRM(png_ptr,
info_ptr->x_white, info_ptr->y_white,
info_ptr->x_red, info_ptr->y_red,
info_ptr->x_green, info_ptr->y_green,
info_ptr->x_blue, info_ptr->y_blue);
#else
# ifdef PNG_FIXED_POINT_SUPPORTED
png_write_cHRM_fixed(png_ptr,
info_ptr->int_x_white, info_ptr->int_y_white,
info_ptr->int_x_red, info_ptr->int_y_red,
info_ptr->int_x_green, info_ptr->int_y_green,
info_ptr->int_x_blue, info_ptr->int_y_blue);
# endif
#endif
}
#endif
#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
if (info_ptr->unknown_chunks_num)
{
png_unknown_chunk *up;
png_debug(5, "writing extra chunks");
for (up = info_ptr->unknown_chunks;
up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
up++)
{
int keep = png_handle_as_unknown(png_ptr, up->name);
if (keep != PNG_HANDLE_CHUNK_NEVER &&
up->location && !(up->location & PNG_HAVE_PLTE) &&
!(up->location & PNG_HAVE_IDAT) &&
((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
(png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
{
if (up->size == 0)
png_warning(png_ptr, "Writing zero-length unknown chunk");
png_write_chunk(png_ptr, up->name, up->data, up->size);
}
}
}
#endif
png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE;
}
}
void PNGAPI
png_write_info(png_structp png_ptr, png_infop info_ptr)
{
#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
int i;
#endif
png_debug(1, "in png_write_info");
if (png_ptr == NULL || info_ptr == NULL)
return;
png_write_info_before_PLTE(png_ptr, info_ptr);
if (info_ptr->valid & PNG_INFO_PLTE)
png_write_PLTE(png_ptr, info_ptr->palette,
(png_uint_32)info_ptr->num_palette);
else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
png_error(png_ptr, "Valid palette required for paletted images");
#ifdef PNG_WRITE_tRNS_SUPPORTED
if (info_ptr->valid & PNG_INFO_tRNS)
{
#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
/* Invert the alpha channel (in tRNS) */
if ((png_ptr->transformations & PNG_INVERT_ALPHA) &&
info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
{
int j;
for (j = 0; j<(int)info_ptr->num_trans; j++)
info_ptr->trans_alpha[j] = (png_byte)(255 - info_ptr->trans_alpha[j]);
}
#endif
png_write_tRNS(png_ptr, info_ptr->trans_alpha, &(info_ptr->trans_color),
info_ptr->num_trans, info_ptr->color_type);
}
#endif
#ifdef PNG_WRITE_bKGD_SUPPORTED
if (info_ptr->valid & PNG_INFO_bKGD)
png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);
#endif
#ifdef PNG_WRITE_hIST_SUPPORTED
if (info_ptr->valid & PNG_INFO_hIST)
png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);
#endif
#ifdef PNG_WRITE_oFFs_SUPPORTED
if (info_ptr->valid & PNG_INFO_oFFs)
png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,
info_ptr->offset_unit_type);
#endif
#ifdef PNG_WRITE_pCAL_SUPPORTED
if (info_ptr->valid & PNG_INFO_pCAL)
png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,
info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,
info_ptr->pcal_units, info_ptr->pcal_params);
#endif
#ifdef PNG_sCAL_SUPPORTED
if (info_ptr->valid & PNG_INFO_sCAL)
#ifdef PNG_WRITE_sCAL_SUPPORTED
#if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_STDIO_SUPPORTED)
png_write_sCAL(png_ptr, (int)info_ptr->scal_unit,
info_ptr->scal_pixel_width, info_ptr->scal_pixel_height);
#else /* !FLOATING_POINT */
#ifdef PNG_FIXED_POINT_SUPPORTED
png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit,
info_ptr->scal_s_width, info_ptr->scal_s_height);
#endif /* FIXED_POINT */
#endif /* FLOATING_POINT */
#else /* !WRITE_sCAL */
png_warning(png_ptr,
"png_write_sCAL not supported; sCAL chunk not written");
#endif /* WRITE_sCAL */
#endif /* sCAL */
#ifdef PNG_WRITE_pHYs_SUPPORTED
if (info_ptr->valid & PNG_INFO_pHYs)
png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,
info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);
#endif /* pHYs */
#ifdef PNG_WRITE_tIME_SUPPORTED
if (info_ptr->valid & PNG_INFO_tIME)
{
png_write_tIME(png_ptr, &(info_ptr->mod_time));
png_ptr->mode |= PNG_WROTE_tIME;
}
#endif /* tIME */
#ifdef PNG_WRITE_sPLT_SUPPORTED
if (info_ptr->valid & PNG_INFO_sPLT)
for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);
#endif /* sPLT */
#ifdef PNG_WRITE_TEXT_SUPPORTED
/* Check to see if we need to write text chunks */
for (i = 0; i < info_ptr->num_text; i++)
{
png_debug2(2, "Writing header text chunk %d, type %d", i,
info_ptr->text[i].compression);
/* An internationalized chunk? */
if (info_ptr->text[i].compression > 0)
{
#ifdef PNG_WRITE_iTXt_SUPPORTED
/* Write international chunk */
png_write_iTXt(png_ptr,
info_ptr->text[i].compression,
info_ptr->text[i].key,
info_ptr->text[i].lang,
info_ptr->text[i].lang_key,
info_ptr->text[i].text);
#else
png_warning(png_ptr, "Unable to write international text");
#endif
/* Mark this chunk as written */
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
}
/* If we want a compressed text chunk */
else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt)
{
#ifdef PNG_WRITE_zTXt_SUPPORTED
/* Write compressed chunk */
png_write_zTXt(png_ptr, info_ptr->text[i].key,
info_ptr->text[i].text, 0,
info_ptr->text[i].compression);
#else
png_warning(png_ptr, "Unable to write compressed text");
#endif
/* Mark this chunk as written */
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
}
else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
{
#ifdef PNG_WRITE_tEXt_SUPPORTED
/* Write uncompressed chunk */
png_write_tEXt(png_ptr, info_ptr->text[i].key,
info_ptr->text[i].text,
0);
/* Mark this chunk as written */
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
#else
/* Can't get here */
png_warning(png_ptr, "Unable to write uncompressed text");
#endif
}
}
#endif /* tEXt */
#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
if (info_ptr->unknown_chunks_num)
{
png_unknown_chunk *up;
png_debug(5, "writing extra chunks");
for (up = info_ptr->unknown_chunks;
up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
up++)
{
int keep = png_handle_as_unknown(png_ptr, up->name);
if (keep != PNG_HANDLE_CHUNK_NEVER &&
up->location && (up->location & PNG_HAVE_PLTE) &&
!(up->location & PNG_HAVE_IDAT) &&
!(up->location & PNG_AFTER_IDAT) &&
((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
(png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
{
png_write_chunk(png_ptr, up->name, up->data, up->size);
}
}
}
#endif
}
/* Writes the end of the PNG file. If you don't want to write comments or
* time information, you can pass NULL for info. If you already wrote these
* in png_write_info(), do not write them again here. If you have long
* comments, I suggest writing them here, and compressing them.
*/
void PNGAPI
png_write_end(png_structp png_ptr, png_infop info_ptr)
{
png_debug(1, "in png_write_end");
if (png_ptr == NULL)
return;
if (!(png_ptr->mode & PNG_HAVE_IDAT))
png_error(png_ptr, "No IDATs written into file");
#if defined(PNG_WRITE_APNG_SUPPORTED)
if (png_ptr->num_frames_written != png_ptr->num_frames_to_write)
png_error(png_ptr, "Not enough frames written");
#endif
/* See if user wants us to write information chunks */
if (info_ptr != NULL)
{
#ifdef PNG_WRITE_TEXT_SUPPORTED
int i; /* local index variable */
#endif
#ifdef PNG_WRITE_tIME_SUPPORTED
/* Check to see if user has supplied a time chunk */
if ((info_ptr->valid & PNG_INFO_tIME) &&
!(png_ptr->mode & PNG_WROTE_tIME))
png_write_tIME(png_ptr, &(info_ptr->mod_time));
#endif
#ifdef PNG_WRITE_TEXT_SUPPORTED
/* Loop through comment chunks */
for (i = 0; i < info_ptr->num_text; i++)
{
png_debug2(2, "Writing trailer text chunk %d, type %d", i,
info_ptr->text[i].compression);
/* An internationalized chunk? */
if (info_ptr->text[i].compression > 0)
{
#ifdef PNG_WRITE_iTXt_SUPPORTED
/* Write international chunk */
png_write_iTXt(png_ptr,
info_ptr->text[i].compression,
info_ptr->text[i].key,
info_ptr->text[i].lang,
info_ptr->text[i].lang_key,
info_ptr->text[i].text);
#else
png_warning(png_ptr, "Unable to write international text");
#endif
/* Mark this chunk as written */
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
}
else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt)
{
#ifdef PNG_WRITE_zTXt_SUPPORTED
/* Write compressed chunk */
png_write_zTXt(png_ptr, info_ptr->text[i].key,
info_ptr->text[i].text, 0,
info_ptr->text[i].compression);
#else
png_warning(png_ptr, "Unable to write compressed text");
#endif
/* Mark this chunk as written */
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
}
else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
{
#ifdef PNG_WRITE_tEXt_SUPPORTED
/* Write uncompressed chunk */
png_write_tEXt(png_ptr, info_ptr->text[i].key,
info_ptr->text[i].text, 0);
#else
png_warning(png_ptr, "Unable to write uncompressed text");
#endif
/* Mark this chunk as written */
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
}
}
#endif
#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
if (info_ptr->unknown_chunks_num)
{
png_unknown_chunk *up;
png_debug(5, "writing extra chunks");
for (up = info_ptr->unknown_chunks;
up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
up++)
{
int keep = png_handle_as_unknown(png_ptr, up->name);
if (keep != PNG_HANDLE_CHUNK_NEVER &&
up->location && (up->location & PNG_AFTER_IDAT) &&
((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
(png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
{
png_write_chunk(png_ptr, up->name, up->data, up->size);
}
}
}
#endif
}
png_ptr->mode |= PNG_AFTER_IDAT;
/* Write end of PNG file */
png_write_IEND(png_ptr);
/* This flush, added in libpng-1.0.8, removed from libpng-1.0.9beta03,
* and restored again in libpng-1.2.30, may cause some applications that
* do not set png_ptr->output_flush_fn to crash. If your application
* experiences a problem, please try building libpng with
* PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED defined, and report the event to
* png-mng-implement at lists.sf.net .
*/
#ifdef PNG_WRITE_FLUSH_SUPPORTED
# ifdef PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED
png_flush(png_ptr);
# endif
#endif
}
#ifdef PNG_CONVERT_tIME_SUPPORTED
/* "tm" structure is not supported on WindowsCE */
void PNGAPI
png_convert_from_struct_tm(png_timep ptime, struct tm FAR * ttime)
{
png_debug(1, "in png_convert_from_struct_tm");
ptime->year = (png_uint_16)(1900 + ttime->tm_year);
ptime->month = (png_byte)(ttime->tm_mon + 1);
ptime->day = (png_byte)ttime->tm_mday;
ptime->hour = (png_byte)ttime->tm_hour;
ptime->minute = (png_byte)ttime->tm_min;
ptime->second = (png_byte)ttime->tm_sec;
}
void PNGAPI
png_convert_from_time_t(png_timep ptime, time_t ttime)
{
struct tm *tbuf;
png_debug(1, "in png_convert_from_time_t");
tbuf = gmtime(&ttime);
png_convert_from_struct_tm(ptime, tbuf);
}
#endif
/* Initialize png_ptr structure, and allocate any memory needed */
png_structp PNGAPI
png_create_write_struct(png_const_charp user_png_ver, png_voidp error_ptr,
png_error_ptr error_fn, png_error_ptr warn_fn)
{
#ifdef PNG_USER_MEM_SUPPORTED
return (png_create_write_struct_2(user_png_ver, error_ptr, error_fn,
warn_fn, NULL, NULL, NULL));
}
/* Alternate initialize png_ptr structure, and allocate any memory needed */
png_structp PNGAPI
png_create_write_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
png_malloc_ptr malloc_fn, png_free_ptr free_fn)
{
#endif /* PNG_USER_MEM_SUPPORTED */
volatile int png_cleanup_needed = 0;
#ifdef PNG_SETJMP_SUPPORTED
volatile
#endif
png_structp png_ptr;
#ifdef PNG_SETJMP_SUPPORTED
#ifdef USE_FAR_KEYWORD
jmp_buf jmpbuf;
#endif
#endif
int i;
png_debug(1, "in png_create_write_struct");
#ifdef PNG_USER_MEM_SUPPORTED
png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
(png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr);
#else
png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
#endif /* PNG_USER_MEM_SUPPORTED */
if (png_ptr == NULL)
return (NULL);
/* Added at libpng-1.2.6 */
#ifdef PNG_SET_USER_LIMITS_SUPPORTED
png_ptr->user_width_max = PNG_USER_WIDTH_MAX;
png_ptr->user_height_max = PNG_USER_HEIGHT_MAX;
#endif
#ifdef PNG_SETJMP_SUPPORTED
/* Applications that neglect to set up their own setjmp() and then
encounter a png_error() will longjmp here. Since the jmpbuf is
then meaningless we abort instead of returning. */
#ifdef USE_FAR_KEYWORD
if (setjmp(jmpbuf))
#else
if (setjmp(png_jmpbuf(png_ptr))) /* sets longjmp to match setjmp */
#endif
#ifdef USE_FAR_KEYWORD
png_memcpy(png_jmpbuf(png_ptr), jmpbuf, png_sizeof(jmp_buf));
#endif
PNG_ABORT();
#endif
#ifdef PNG_USER_MEM_SUPPORTED
png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
#endif /* PNG_USER_MEM_SUPPORTED */
png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
if (user_png_ver)
{
i = 0;
do
{
if (user_png_ver[i] != png_libpng_ver[i])
png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
} while (png_libpng_ver[i++]);
}
if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
{
/* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
* we must recompile any applications that use any older library version.
* For versions after libpng 1.0, we will be compatible, so we need
* only check the first digit.
*/
if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
(user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
(user_png_ver[0] == '0' && user_png_ver[2] < '9'))
{
#ifdef PNG_STDIO_SUPPORTED
char msg[80];
if (user_png_ver)
{
png_snprintf(msg, 80,
"Application was compiled with png.h from libpng-%.20s",
user_png_ver);
png_warning(png_ptr, msg);
}
png_snprintf(msg, 80,
"Application is running with png.c from libpng-%.20s",
png_libpng_ver);
png_warning(png_ptr, msg);
#endif
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
png_ptr->flags = 0;
#endif
png_warning(png_ptr,
"Incompatible libpng version in application and library");
png_cleanup_needed = 1;
}
}
/* Initialize zbuf - compression buffer */
png_ptr->zbuf_size = PNG_ZBUF_SIZE;
if (!png_cleanup_needed)
{
png_ptr->zbuf = (png_bytep)png_malloc_warn(png_ptr,
png_ptr->zbuf_size);
if (png_ptr->zbuf == NULL)
png_cleanup_needed = 1;
}
if (png_cleanup_needed)
{
/* Clean up PNG structure and deallocate any memory. */
png_free(png_ptr, png_ptr->zbuf);
png_ptr->zbuf = NULL;
#ifdef PNG_USER_MEM_SUPPORTED
png_destroy_struct_2((png_voidp)png_ptr,
(png_free_ptr)free_fn, (png_voidp)mem_ptr);
#else
png_destroy_struct((png_voidp)png_ptr);
#endif
return (NULL);
}
png_set_write_fn(png_ptr, NULL, NULL, NULL);
#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
png_set_filter_heuristics(png_ptr, PNG_FILTER_HEURISTIC_DEFAULT,
1, NULL, NULL);
#endif
return (png_ptr);
}
/* Write a few rows of image data. If the image is interlaced,
* either you will have to write the 7 sub images, or, if you
* have called png_set_interlace_handling(), you will have to
* "write" the image seven times.
*/
void PNGAPI
png_write_rows(png_structp png_ptr, png_bytepp row,
png_uint_32 num_rows)
{
png_uint_32 i; /* row counter */
png_bytepp rp; /* row pointer */
png_debug(1, "in png_write_rows");
if (png_ptr == NULL)
return;
/* Loop through the rows */
for (i = 0, rp = row; i < num_rows; i++, rp++)
{
png_write_row(png_ptr, *rp);
}
}
/* Write the image. You only need to call this function once, even
* if you are writing an interlaced image.
*/
void PNGAPI
png_write_image(png_structp png_ptr, png_bytepp image)
{
png_uint_32 i; /* row index */
int pass, num_pass; /* pass variables */
png_bytepp rp; /* points to current row */
if (png_ptr == NULL)
return;
png_debug(1, "in png_write_image");
#ifdef PNG_WRITE_INTERLACING_SUPPORTED
/* Initialize interlace handling. If image is not interlaced,
* this will set pass to 1
*/
num_pass = png_set_interlace_handling(png_ptr);
#else
num_pass = 1;
#endif
/* Loop through passes */
for (pass = 0; pass < num_pass; pass++)
{
/* Loop through image */
for (i = 0, rp = image; i < png_ptr->height; i++, rp++)
{
png_write_row(png_ptr, *rp);
}
}
}
/* Called by user to write a row of image data */
void PNGAPI
png_write_row(png_structp png_ptr, png_bytep row)
{
if (png_ptr == NULL)
return;
png_debug2(1, "in png_write_row (row %lu, pass %d)",
(unsigned long)png_ptr->row_number, png_ptr->pass);
/* Initialize transformations and other stuff if first time */
if (png_ptr->row_number == 0 && png_ptr->pass == 0)
{
/* Make sure we wrote the header info */
if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
png_error(png_ptr,
"png_write_info was never called before png_write_row");
/* Check for transforms that have been set but were defined out */
#if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED)
if (png_ptr->transformations & PNG_INVERT_MONO)
png_warning(png_ptr, "PNG_WRITE_INVERT_SUPPORTED is not defined");
#endif
#if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED)
if (png_ptr->transformations & PNG_FILLER)
png_warning(png_ptr, "PNG_WRITE_FILLER_SUPPORTED is not defined");
#endif
#if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && \
defined(PNG_READ_PACKSWAP_SUPPORTED)
if (png_ptr->transformations & PNG_PACKSWAP)
png_warning(png_ptr,
"PNG_WRITE_PACKSWAP_SUPPORTED is not defined");
#endif
#if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED)
if (png_ptr->transformations & PNG_PACK)
png_warning(png_ptr, "PNG_WRITE_PACK_SUPPORTED is not defined");
#endif
#if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED)
if (png_ptr->transformations & PNG_SHIFT)
png_warning(png_ptr, "PNG_WRITE_SHIFT_SUPPORTED is not defined");
#endif
#if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED)
if (png_ptr->transformations & PNG_BGR)
png_warning(png_ptr, "PNG_WRITE_BGR_SUPPORTED is not defined");
#endif
#if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED)
if (png_ptr->transformations & PNG_SWAP_BYTES)
png_warning(png_ptr, "PNG_WRITE_SWAP_SUPPORTED is not defined");
#endif
png_write_start_row(png_ptr);
}
#ifdef PNG_WRITE_INTERLACING_SUPPORTED
/* If interlaced and not interested in row, return */
if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
{
switch (png_ptr->pass)
{
case 0:
if (png_ptr->row_number & 0x07)
{
png_write_finish_row(png_ptr);
return;
}
break;
case 1:
if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
{
png_write_finish_row(png_ptr);
return;
}
break;
case 2:
if ((png_ptr->row_number & 0x07) != 4)
{
png_write_finish_row(png_ptr);
return;
}
break;
case 3:
if ((png_ptr->row_number & 0x03) || png_ptr->width < 3)
{
png_write_finish_row(png_ptr);
return;
}
break;
case 4:
if ((png_ptr->row_number & 0x03) != 2)
{
png_write_finish_row(png_ptr);
return;
}
break;
case 5:
if ((png_ptr->row_number & 0x01) || png_ptr->width < 2)
{
png_write_finish_row(png_ptr);
return;
}
break;
case 6:
if (!(png_ptr->row_number & 0x01))
{
png_write_finish_row(png_ptr);
return;
}
break;
}
}
#endif
/* Set up row info for transformations */
png_ptr->row_info.color_type = png_ptr->color_type;
png_ptr->row_info.width = png_ptr->usr_width;
png_ptr->row_info.channels = png_ptr->usr_channels;
png_ptr->row_info.bit_depth = png_ptr->usr_bit_depth;
png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth *
png_ptr->row_info.channels);
png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
png_ptr->row_info.width);
png_debug1(3, "row_info->color_type = %d", png_ptr->row_info.color_type);
png_debug1(3, "row_info->width = %lu",
(unsigned long)png_ptr->row_info.width);
png_debug1(3, "row_info->channels = %d", png_ptr->row_info.channels);
png_debug1(3, "row_info->bit_depth = %d", png_ptr->row_info.bit_depth);
png_debug1(3, "row_info->pixel_depth = %d", png_ptr->row_info.pixel_depth);
png_debug1(3, "row_info->rowbytes = %lu", png_ptr->row_info.rowbytes);
/* Copy user's row into buffer, leaving room for filter byte. */
png_memcpy(png_ptr->row_buf + 1, row, png_ptr->row_info.rowbytes);
#ifdef PNG_WRITE_INTERLACING_SUPPORTED
/* Handle interlacing */
if (png_ptr->interlaced && png_ptr->pass < 6 &&
(png_ptr->transformations & PNG_INTERLACE))
{
png_do_write_interlace(&(png_ptr->row_info),
png_ptr->row_buf + 1, png_ptr->pass);
/* This should always get caught above, but still ... */
if (!(png_ptr->row_info.width))
{
png_write_finish_row(png_ptr);
return;
}
}
#endif
/* Handle other transformations */
if (png_ptr->transformations)
png_do_write_transformations(png_ptr);
#ifdef PNG_MNG_FEATURES_SUPPORTED
/* Write filter_method 64 (intrapixel differencing) only if
* 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
* 2. Libpng did not write a PNG signature (this filter_method is only
* used in PNG datastreams that are embedded in MNG datastreams) and
* 3. The application called png_permit_mng_features with a mask that
* included PNG_FLAG_MNG_FILTER_64 and
* 4. The filter_method is 64 and
* 5. The color_type is RGB or RGBA
*/
if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
(png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
{
/* Intrapixel differencing */
png_do_write_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1);
}
#endif
/* Find a filter if necessary, filter the row and write it out. */
png_write_find_filter(png_ptr, &(png_ptr->row_info));
if (png_ptr->write_row_fn != NULL)
(*(png_ptr->write_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);
}
#ifdef PNG_WRITE_FLUSH_SUPPORTED
/* Set the automatic flush interval or 0 to turn flushing off */
void PNGAPI
png_set_flush(png_structp png_ptr, int nrows)
{
png_debug(1, "in png_set_flush");
if (png_ptr == NULL)
return;
png_ptr->flush_dist = (nrows < 0 ? 0 : nrows);
}
/* Flush the current output buffers now */
void PNGAPI
png_write_flush(png_structp png_ptr)
{
int wrote_IDAT;
png_debug(1, "in png_write_flush");
if (png_ptr == NULL)
return;
/* We have already written out all of the data */
if (png_ptr->row_number >= png_ptr->num_rows)
return;
do
{
int ret;
/* Compress the data */
ret = deflate(&png_ptr->zstream, Z_SYNC_FLUSH);
wrote_IDAT = 0;
/* Check for compression errors */
if (ret != Z_OK)
{
if (png_ptr->zstream.msg != NULL)
png_error(png_ptr, png_ptr->zstream.msg);
else
png_error(png_ptr, "zlib error");
}
if (!(png_ptr->zstream.avail_out))
{
/* Write the IDAT and reset the zlib output buffer */
png_write_IDAT(png_ptr, png_ptr->zbuf,
png_ptr->zbuf_size);
png_ptr->zstream.next_out = png_ptr->zbuf;
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
wrote_IDAT = 1;
}
} while(wrote_IDAT == 1);
/* If there is any data left to be output, write it into a new IDAT */
if (png_ptr->zbuf_size != png_ptr->zstream.avail_out)
{
/* Write the IDAT and reset the zlib output buffer */
png_write_IDAT(png_ptr, png_ptr->zbuf,
png_ptr->zbuf_size - png_ptr->zstream.avail_out);
png_ptr->zstream.next_out = png_ptr->zbuf;
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
}
png_ptr->flush_rows = 0;
png_flush(png_ptr);
}
#endif /* PNG_WRITE_FLUSH_SUPPORTED */
/* Free all memory used by the write */
void PNGAPI
png_destroy_write_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)
{
png_structp png_ptr = NULL;
png_infop info_ptr = NULL;
#ifdef PNG_USER_MEM_SUPPORTED
png_free_ptr free_fn = NULL;
png_voidp mem_ptr = NULL;
#endif
png_debug(1, "in png_destroy_write_struct");
if (png_ptr_ptr != NULL)
{
png_ptr = *png_ptr_ptr;
#ifdef PNG_USER_MEM_SUPPORTED
free_fn = png_ptr->free_fn;
mem_ptr = png_ptr->mem_ptr;
#endif
}
#ifdef PNG_USER_MEM_SUPPORTED
if (png_ptr != NULL)
{
free_fn = png_ptr->free_fn;
mem_ptr = png_ptr->mem_ptr;
}
#endif
if (info_ptr_ptr != NULL)
info_ptr = *info_ptr_ptr;
if (info_ptr != NULL)
{
if (png_ptr != NULL)
{
png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
if (png_ptr->num_chunk_list)
{
png_free(png_ptr, png_ptr->chunk_list);
png_ptr->num_chunk_list = 0;
}
#endif
}
#ifdef PNG_USER_MEM_SUPPORTED
png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn,
(png_voidp)mem_ptr);
#else
png_destroy_struct((png_voidp)info_ptr);
#endif
*info_ptr_ptr = NULL;
}
if (png_ptr != NULL)
{
png_write_destroy(png_ptr);
#ifdef PNG_USER_MEM_SUPPORTED
png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn,
(png_voidp)mem_ptr);
#else
png_destroy_struct((png_voidp)png_ptr);
#endif
*png_ptr_ptr = NULL;
}
}
/* Free any memory used in png_ptr struct (old method) */
void /* PRIVATE */
png_write_destroy(png_structp png_ptr)
{
#ifdef PNG_SETJMP_SUPPORTED
jmp_buf tmp_jmp; /* Save jump buffer */
#endif
png_error_ptr error_fn;
png_error_ptr warning_fn;
png_voidp error_ptr;
#ifdef PNG_USER_MEM_SUPPORTED
png_free_ptr free_fn;
#endif
png_debug(1, "in png_write_destroy");
/* Free any memory zlib uses */