forked from FFmpeg/FFmpeg
/
pngdec.c
1886 lines (1659 loc) · 63.8 KB
/
pngdec.c
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/*
* PNG image format
* Copyright (c) 2003 Fabrice Bellard
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
//#define DEBUG
#include "config_components.h"
#include "libavutil/avassert.h"
#include "libavutil/bprint.h"
#include "libavutil/crc.h"
#include "libavutil/csp.h"
#include "libavutil/imgutils.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/pixfmt.h"
#include "libavutil/rational.h"
#include "libavutil/stereo3d.h"
#include "avcodec.h"
#include "bytestream.h"
#include "codec_internal.h"
#include "decode.h"
#include "apng.h"
#include "png.h"
#include "pngdsp.h"
#include "thread.h"
#include "threadframe.h"
#include "zlib_wrapper.h"
#include <zlib.h>
enum PNGHeaderState {
PNG_IHDR = 1 << 0,
PNG_PLTE = 1 << 1,
};
enum PNGImageState {
PNG_IDAT = 1 << 0,
PNG_ALLIMAGE = 1 << 1,
};
typedef struct PNGDecContext {
PNGDSPContext dsp;
AVCodecContext *avctx;
GetByteContext gb;
ThreadFrame last_picture;
ThreadFrame picture;
AVDictionary *frame_metadata;
uint8_t iccp_name[82];
uint8_t *iccp_data;
size_t iccp_data_len;
int stereo_mode;
int have_chrm;
uint32_t white_point[2];
uint32_t display_primaries[3][2];
int gamma;
int have_srgb;
int have_cicp;
enum AVColorPrimaries cicp_primaries;
enum AVColorTransferCharacteristic cicp_trc;
enum AVColorRange cicp_range;
enum PNGHeaderState hdr_state;
enum PNGImageState pic_state;
int width, height;
int cur_w, cur_h;
int x_offset, y_offset;
uint8_t dispose_op, blend_op;
int bit_depth;
int color_type;
int compression_type;
int interlace_type;
int filter_type;
int channels;
int bits_per_pixel;
int bpp;
int has_trns;
uint8_t transparent_color_be[6];
int significant_bits;
uint32_t palette[256];
uint8_t *crow_buf;
uint8_t *last_row;
unsigned int last_row_size;
uint8_t *tmp_row;
unsigned int tmp_row_size;
uint8_t *buffer;
int buffer_size;
int pass;
int crow_size; /* compressed row size (include filter type) */
int row_size; /* decompressed row size */
int pass_row_size; /* decompress row size of the current pass */
int y;
FFZStream zstream;
} PNGDecContext;
/* Mask to determine which pixels are valid in a pass */
static const uint8_t png_pass_mask[NB_PASSES] = {
0x01, 0x01, 0x11, 0x11, 0x55, 0x55, 0xff,
};
/* Mask to determine which y pixels can be written in a pass */
static const uint8_t png_pass_dsp_ymask[NB_PASSES] = {
0xff, 0xff, 0x0f, 0xff, 0x33, 0xff, 0x55,
};
/* Mask to determine which pixels to overwrite while displaying */
static const uint8_t png_pass_dsp_mask[NB_PASSES] = {
0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff
};
/* NOTE: we try to construct a good looking image at each pass. width
* is the original image width. We also do pixel format conversion at
* this stage */
static void png_put_interlaced_row(uint8_t *dst, int width,
int bits_per_pixel, int pass,
int color_type, const uint8_t *src)
{
int x, mask, dsp_mask, j, src_x, b, bpp;
uint8_t *d;
const uint8_t *s;
mask = png_pass_mask[pass];
dsp_mask = png_pass_dsp_mask[pass];
switch (bits_per_pixel) {
case 1:
src_x = 0;
for (x = 0; x < width; x++) {
j = (x & 7);
if ((dsp_mask << j) & 0x80) {
b = (src[src_x >> 3] >> (7 - (src_x & 7))) & 1;
dst[x >> 3] &= 0xFF7F>>j;
dst[x >> 3] |= b << (7 - j);
}
if ((mask << j) & 0x80)
src_x++;
}
break;
case 2:
src_x = 0;
for (x = 0; x < width; x++) {
int j2 = 2 * (x & 3);
j = (x & 7);
if ((dsp_mask << j) & 0x80) {
b = (src[src_x >> 2] >> (6 - 2*(src_x & 3))) & 3;
dst[x >> 2] &= 0xFF3F>>j2;
dst[x >> 2] |= b << (6 - j2);
}
if ((mask << j) & 0x80)
src_x++;
}
break;
case 4:
src_x = 0;
for (x = 0; x < width; x++) {
int j2 = 4*(x&1);
j = (x & 7);
if ((dsp_mask << j) & 0x80) {
b = (src[src_x >> 1] >> (4 - 4*(src_x & 1))) & 15;
dst[x >> 1] &= 0xFF0F>>j2;
dst[x >> 1] |= b << (4 - j2);
}
if ((mask << j) & 0x80)
src_x++;
}
break;
default:
bpp = bits_per_pixel >> 3;
d = dst;
s = src;
for (x = 0; x < width; x++) {
j = x & 7;
if ((dsp_mask << j) & 0x80) {
memcpy(d, s, bpp);
}
d += bpp;
if ((mask << j) & 0x80)
s += bpp;
}
break;
}
}
void ff_add_png_paeth_prediction(uint8_t *dst, uint8_t *src, uint8_t *top,
int w, int bpp)
{
int i;
for (i = 0; i < w; i++) {
int a, b, c, p, pa, pb, pc;
a = dst[i - bpp];
b = top[i];
c = top[i - bpp];
p = b - c;
pc = a - c;
pa = abs(p);
pb = abs(pc);
pc = abs(p + pc);
if (pa <= pb && pa <= pc)
p = a;
else if (pb <= pc)
p = b;
else
p = c;
dst[i] = p + src[i];
}
}
#define UNROLL1(bpp, op) \
{ \
r = dst[0]; \
if (bpp >= 2) \
g = dst[1]; \
if (bpp >= 3) \
b = dst[2]; \
if (bpp >= 4) \
a = dst[3]; \
for (; i <= size - bpp; i += bpp) { \
dst[i + 0] = r = op(r, src[i + 0], last[i + 0]); \
if (bpp == 1) \
continue; \
dst[i + 1] = g = op(g, src[i + 1], last[i + 1]); \
if (bpp == 2) \
continue; \
dst[i + 2] = b = op(b, src[i + 2], last[i + 2]); \
if (bpp == 3) \
continue; \
dst[i + 3] = a = op(a, src[i + 3], last[i + 3]); \
} \
}
#define UNROLL_FILTER(op) \
if (bpp == 1) { \
UNROLL1(1, op) \
} else if (bpp == 2) { \
UNROLL1(2, op) \
} else if (bpp == 3) { \
UNROLL1(3, op) \
} else if (bpp == 4) { \
UNROLL1(4, op) \
} \
for (; i < size; i++) { \
dst[i] = op(dst[i - bpp], src[i], last[i]); \
}
/* NOTE: 'dst' can be equal to 'last' */
void ff_png_filter_row(PNGDSPContext *dsp, uint8_t *dst, int filter_type,
uint8_t *src, uint8_t *last, int size, int bpp)
{
int i, p, r, g, b, a;
switch (filter_type) {
case PNG_FILTER_VALUE_NONE:
memcpy(dst, src, size);
break;
case PNG_FILTER_VALUE_SUB:
for (i = 0; i < bpp; i++)
dst[i] = src[i];
if (bpp == 4) {
p = *(int *)dst;
for (; i < size; i += bpp) {
unsigned s = *(int *)(src + i);
p = ((s & 0x7f7f7f7f) + (p & 0x7f7f7f7f)) ^ ((s ^ p) & 0x80808080);
*(int *)(dst + i) = p;
}
} else {
#define OP_SUB(x, s, l) ((x) + (s))
UNROLL_FILTER(OP_SUB);
}
break;
case PNG_FILTER_VALUE_UP:
dsp->add_bytes_l2(dst, src, last, size);
break;
case PNG_FILTER_VALUE_AVG:
for (i = 0; i < bpp; i++) {
p = (last[i] >> 1);
dst[i] = p + src[i];
}
#define OP_AVG(x, s, l) (((((x) + (l)) >> 1) + (s)) & 0xff)
UNROLL_FILTER(OP_AVG);
break;
case PNG_FILTER_VALUE_PAETH:
for (i = 0; i < bpp; i++) {
p = last[i];
dst[i] = p + src[i];
}
if (bpp > 2 && size > 4) {
/* would write off the end of the array if we let it process
* the last pixel with bpp=3 */
int w = (bpp & 3) ? size - 3 : size;
if (w > i) {
dsp->add_paeth_prediction(dst + i, src + i, last + i, size - i, bpp);
i = w;
}
}
ff_add_png_paeth_prediction(dst + i, src + i, last + i, size - i, bpp);
break;
}
}
/* This used to be called "deloco" in FFmpeg
* and is actually an inverse reversible colorspace transformation */
#define YUV2RGB(NAME, TYPE) \
static void deloco_ ## NAME(TYPE *dst, int size, int alpha) \
{ \
int i; \
for (i = 0; i < size - 2; i += 3 + alpha) { \
int g = dst [i + 1]; \
dst[i + 0] += g; \
dst[i + 2] += g; \
} \
}
YUV2RGB(rgb8, uint8_t)
YUV2RGB(rgb16, uint16_t)
static int percent_missing(PNGDecContext *s)
{
if (s->interlace_type) {
return 100 - 100 * s->pass / (NB_PASSES - 1);
} else {
return 100 - 100 * s->y / s->cur_h;
}
}
/* process exactly one decompressed row */
static void png_handle_row(PNGDecContext *s, uint8_t *dst, ptrdiff_t dst_stride)
{
uint8_t *ptr, *last_row;
int got_line;
if (!s->interlace_type) {
ptr = dst + dst_stride * (s->y + s->y_offset) + s->x_offset * s->bpp;
if (s->y == 0)
last_row = s->last_row;
else
last_row = ptr - dst_stride;
ff_png_filter_row(&s->dsp, ptr, s->crow_buf[0], s->crow_buf + 1,
last_row, s->row_size, s->bpp);
/* loco lags by 1 row so that it doesn't interfere with top prediction */
if (s->filter_type == PNG_FILTER_TYPE_LOCO && s->y > 0) {
if (s->bit_depth == 16) {
deloco_rgb16((uint16_t *)(ptr - dst_stride), s->row_size / 2,
s->color_type == PNG_COLOR_TYPE_RGB_ALPHA);
} else {
deloco_rgb8(ptr - dst_stride, s->row_size,
s->color_type == PNG_COLOR_TYPE_RGB_ALPHA);
}
}
s->y++;
if (s->y == s->cur_h) {
s->pic_state |= PNG_ALLIMAGE;
if (s->filter_type == PNG_FILTER_TYPE_LOCO) {
if (s->bit_depth == 16) {
deloco_rgb16((uint16_t *)ptr, s->row_size / 2,
s->color_type == PNG_COLOR_TYPE_RGB_ALPHA);
} else {
deloco_rgb8(ptr, s->row_size,
s->color_type == PNG_COLOR_TYPE_RGB_ALPHA);
}
}
}
} else {
got_line = 0;
for (;;) {
ptr = dst + dst_stride * (s->y + s->y_offset) + s->x_offset * s->bpp;
if ((ff_png_pass_ymask[s->pass] << (s->y & 7)) & 0x80) {
/* if we already read one row, it is time to stop to
* wait for the next one */
if (got_line)
break;
ff_png_filter_row(&s->dsp, s->tmp_row, s->crow_buf[0], s->crow_buf + 1,
s->last_row, s->pass_row_size, s->bpp);
FFSWAP(uint8_t *, s->last_row, s->tmp_row);
FFSWAP(unsigned int, s->last_row_size, s->tmp_row_size);
got_line = 1;
}
if ((png_pass_dsp_ymask[s->pass] << (s->y & 7)) & 0x80) {
png_put_interlaced_row(ptr, s->cur_w, s->bits_per_pixel, s->pass,
s->color_type, s->last_row);
}
s->y++;
if (s->y == s->cur_h) {
memset(s->last_row, 0, s->row_size);
for (;;) {
if (s->pass == NB_PASSES - 1) {
s->pic_state |= PNG_ALLIMAGE;
goto the_end;
} else {
s->pass++;
s->y = 0;
s->pass_row_size = ff_png_pass_row_size(s->pass,
s->bits_per_pixel,
s->cur_w);
s->crow_size = s->pass_row_size + 1;
if (s->pass_row_size != 0)
break;
/* skip pass if empty row */
}
}
}
}
the_end:;
}
}
static int png_decode_idat(PNGDecContext *s, GetByteContext *gb,
uint8_t *dst, ptrdiff_t dst_stride)
{
z_stream *const zstream = &s->zstream.zstream;
int ret;
zstream->avail_in = bytestream2_get_bytes_left(gb);
zstream->next_in = gb->buffer;
/* decode one line if possible */
while (zstream->avail_in > 0) {
ret = inflate(zstream, Z_PARTIAL_FLUSH);
if (ret != Z_OK && ret != Z_STREAM_END) {
av_log(s->avctx, AV_LOG_ERROR, "inflate returned error %d\n", ret);
return AVERROR_EXTERNAL;
}
if (zstream->avail_out == 0) {
if (!(s->pic_state & PNG_ALLIMAGE)) {
png_handle_row(s, dst, dst_stride);
}
zstream->avail_out = s->crow_size;
zstream->next_out = s->crow_buf;
}
if (ret == Z_STREAM_END && zstream->avail_in > 0) {
av_log(s->avctx, AV_LOG_WARNING,
"%d undecompressed bytes left in buffer\n", zstream->avail_in);
return 0;
}
}
return 0;
}
static int decode_zbuf(AVBPrint *bp, const uint8_t *data,
const uint8_t *data_end, void *logctx)
{
FFZStream z;
z_stream *const zstream = &z.zstream;
unsigned char *buf;
unsigned buf_size;
int ret = ff_inflate_init(&z, logctx);
if (ret < 0)
return ret;
zstream->next_in = data;
zstream->avail_in = data_end - data;
av_bprint_init(bp, 0, AV_BPRINT_SIZE_UNLIMITED);
while (zstream->avail_in > 0) {
av_bprint_get_buffer(bp, 2, &buf, &buf_size);
if (buf_size < 2) {
ret = AVERROR(ENOMEM);
goto fail;
}
zstream->next_out = buf;
zstream->avail_out = buf_size - 1;
ret = inflate(zstream, Z_PARTIAL_FLUSH);
if (ret != Z_OK && ret != Z_STREAM_END) {
ret = AVERROR_EXTERNAL;
goto fail;
}
bp->len += zstream->next_out - buf;
if (ret == Z_STREAM_END)
break;
}
ff_inflate_end(&z);
bp->str[bp->len] = 0;
return 0;
fail:
ff_inflate_end(&z);
av_bprint_finalize(bp, NULL);
return ret;
}
static char *iso88591_to_utf8(const char *in, size_t size_in)
{
size_t extra = 0, i;
char *out, *q;
for (i = 0; i < size_in; i++)
extra += !!(in[i] & 0x80);
if (size_in == SIZE_MAX || extra > SIZE_MAX - size_in - 1)
return NULL;
q = out = av_malloc(size_in + extra + 1);
if (!out)
return NULL;
for (i = 0; i < size_in; i++) {
if (in[i] & 0x80) {
*(q++) = 0xC0 | (in[i] >> 6);
*(q++) = 0x80 | (in[i] & 0x3F);
} else {
*(q++) = in[i];
}
}
*(q++) = 0;
return out;
}
static int decode_text_chunk(PNGDecContext *s, GetByteContext *gb, int compressed)
{
int ret, method;
const uint8_t *data = gb->buffer;
const uint8_t *data_end = gb->buffer_end;
const char *keyword = data;
const char *keyword_end = memchr(keyword, 0, data_end - data);
char *kw_utf8 = NULL, *txt_utf8 = NULL;
const char *text;
unsigned text_len;
AVBPrint bp;
if (!keyword_end)
return AVERROR_INVALIDDATA;
data = keyword_end + 1;
if (compressed) {
if (data == data_end)
return AVERROR_INVALIDDATA;
method = *(data++);
if (method)
return AVERROR_INVALIDDATA;
if ((ret = decode_zbuf(&bp, data, data_end, s->avctx)) < 0)
return ret;
text = bp.str;
text_len = bp.len;
} else {
text = data;
text_len = data_end - data;
}
txt_utf8 = iso88591_to_utf8(text, text_len);
if (compressed)
av_bprint_finalize(&bp, NULL);
if (!txt_utf8)
return AVERROR(ENOMEM);
kw_utf8 = iso88591_to_utf8(keyword, keyword_end - keyword);
if (!kw_utf8) {
av_free(txt_utf8);
return AVERROR(ENOMEM);
}
av_dict_set(&s->frame_metadata, kw_utf8, txt_utf8,
AV_DICT_DONT_STRDUP_KEY | AV_DICT_DONT_STRDUP_VAL);
return 0;
}
static int decode_ihdr_chunk(AVCodecContext *avctx, PNGDecContext *s,
GetByteContext *gb)
{
if (bytestream2_get_bytes_left(gb) != 13)
return AVERROR_INVALIDDATA;
if (s->pic_state & PNG_IDAT) {
av_log(avctx, AV_LOG_ERROR, "IHDR after IDAT\n");
return AVERROR_INVALIDDATA;
}
if (s->hdr_state & PNG_IHDR) {
av_log(avctx, AV_LOG_ERROR, "Multiple IHDR\n");
return AVERROR_INVALIDDATA;
}
s->width = s->cur_w = bytestream2_get_be32(gb);
s->height = s->cur_h = bytestream2_get_be32(gb);
if (av_image_check_size(s->width, s->height, 0, avctx)) {
s->cur_w = s->cur_h = s->width = s->height = 0;
av_log(avctx, AV_LOG_ERROR, "Invalid image size\n");
return AVERROR_INVALIDDATA;
}
s->bit_depth = bytestream2_get_byte(gb);
if (s->bit_depth != 1 && s->bit_depth != 2 && s->bit_depth != 4 &&
s->bit_depth != 8 && s->bit_depth != 16) {
av_log(avctx, AV_LOG_ERROR, "Invalid bit depth\n");
goto error;
}
s->color_type = bytestream2_get_byte(gb);
s->compression_type = bytestream2_get_byte(gb);
if (s->compression_type) {
av_log(avctx, AV_LOG_ERROR, "Invalid compression method %d\n", s->compression_type);
goto error;
}
s->filter_type = bytestream2_get_byte(gb);
s->interlace_type = bytestream2_get_byte(gb);
s->hdr_state |= PNG_IHDR;
if (avctx->debug & FF_DEBUG_PICT_INFO)
av_log(avctx, AV_LOG_DEBUG, "width=%d height=%d depth=%d color_type=%d "
"compression_type=%d filter_type=%d interlace_type=%d\n",
s->width, s->height, s->bit_depth, s->color_type,
s->compression_type, s->filter_type, s->interlace_type);
return 0;
error:
s->cur_w = s->cur_h = s->width = s->height = 0;
s->bit_depth = 8;
return AVERROR_INVALIDDATA;
}
static int decode_phys_chunk(AVCodecContext *avctx, PNGDecContext *s,
GetByteContext *gb)
{
if (s->pic_state & PNG_IDAT) {
av_log(avctx, AV_LOG_ERROR, "pHYs after IDAT\n");
return AVERROR_INVALIDDATA;
}
avctx->sample_aspect_ratio.num = bytestream2_get_be32(gb);
avctx->sample_aspect_ratio.den = bytestream2_get_be32(gb);
if (avctx->sample_aspect_ratio.num < 0 || avctx->sample_aspect_ratio.den < 0)
avctx->sample_aspect_ratio = (AVRational){ 0, 1 };
bytestream2_skip(gb, 1); /* unit specifier */
return 0;
}
/*
* This populates AVCodecContext fields so it must be called before
* ff_thread_finish_setup() to avoid a race condition with respect to the
* generic copying of avctx fields.
*/
static int populate_avctx_color_fields(AVCodecContext *avctx, AVFrame *frame)
{
PNGDecContext *s = avctx->priv_data;
if (s->have_cicp) {
if (s->cicp_primaries >= AVCOL_PRI_NB)
av_log(avctx, AV_LOG_WARNING, "unrecognized cICP primaries\n");
else
avctx->color_primaries = frame->color_primaries = s->cicp_primaries;
if (s->cicp_trc >= AVCOL_TRC_NB)
av_log(avctx, AV_LOG_WARNING, "unrecognized cICP transfer\n");
else
avctx->color_trc = frame->color_trc = s->cicp_trc;
if (s->cicp_range == 0)
av_log(avctx, AV_LOG_WARNING, "unsupported tv-range cICP chunk\n");
} else if (s->iccp_data) {
AVFrameSideData *sd = av_frame_new_side_data(frame, AV_FRAME_DATA_ICC_PROFILE, s->iccp_data_len);
if (!sd)
return AVERROR(ENOMEM);
memcpy(sd->data, s->iccp_data, s->iccp_data_len);
av_dict_set(&sd->metadata, "name", s->iccp_name, 0);
} else if (s->have_srgb) {
avctx->color_primaries = frame->color_primaries = AVCOL_PRI_BT709;
avctx->color_trc = frame->color_trc = AVCOL_TRC_IEC61966_2_1;
} else if (s->have_chrm) {
AVColorPrimariesDesc desc;
enum AVColorPrimaries prim;
desc.wp.x = av_make_q(s->white_point[0], 100000);
desc.wp.y = av_make_q(s->white_point[1], 100000);
desc.prim.r.x = av_make_q(s->display_primaries[0][0], 100000);
desc.prim.r.y = av_make_q(s->display_primaries[0][1], 100000);
desc.prim.g.x = av_make_q(s->display_primaries[1][0], 100000);
desc.prim.g.y = av_make_q(s->display_primaries[1][1], 100000);
desc.prim.b.x = av_make_q(s->display_primaries[2][0], 100000);
desc.prim.b.y = av_make_q(s->display_primaries[2][1], 100000);
prim = av_csp_primaries_id_from_desc(&desc);
if (prim != AVCOL_PRI_UNSPECIFIED)
avctx->color_primaries = frame->color_primaries = prim;
else
av_log(avctx, AV_LOG_WARNING, "unknown cHRM primaries\n");
}
/* these chunks override gAMA */
if (s->iccp_data || s->have_srgb || s->have_cicp) {
av_dict_set(&s->frame_metadata, "gamma", NULL, 0);
} else if (s->gamma) {
/*
* These values are 100000/2.2, 100000/2.8, 100000/2.6, and
* 100000/1.0 respectively. 45455, 35714, and 38462, and 100000.
* There's a 0.001 gamma tolerance here in case of floating
* point issues when the PNG was written.
*
* None of the other enums have a pure gamma curve so it makes
* sense to leave those to sRGB and cICP.
*/
if (s->gamma > 45355 && s->gamma < 45555)
avctx->color_trc = frame->color_trc = AVCOL_TRC_GAMMA22;
else if (s->gamma > 35614 && s->gamma < 35814)
avctx->color_trc = frame->color_trc = AVCOL_TRC_GAMMA28;
else if (s->gamma > 38362 && s->gamma < 38562)
avctx->color_trc = frame->color_trc = AVCOL_TRC_SMPTE428;
else if (s->gamma > 99900 && s->gamma < 100100)
avctx->color_trc = frame->color_trc = AVCOL_TRC_LINEAR;
}
/* we only support pc-range RGB */
avctx->colorspace = frame->colorspace = AVCOL_SPC_RGB;
avctx->color_range = frame->color_range = AVCOL_RANGE_JPEG;
/*
* tRNS sets alpha depth to full, so we ignore sBIT if set.
* As a result we must wait until now to set
* avctx->bits_per_raw_sample in case tRNS appears after sBIT
*/
if (!s->has_trns && s->significant_bits > 0)
avctx->bits_per_raw_sample = s->significant_bits;
return 0;
}
static int decode_idat_chunk(AVCodecContext *avctx, PNGDecContext *s,
GetByteContext *gb, AVFrame *p)
{
int ret;
size_t byte_depth = s->bit_depth > 8 ? 2 : 1;
if (!p)
return AVERROR_INVALIDDATA;
if (!(s->hdr_state & PNG_IHDR)) {
av_log(avctx, AV_LOG_ERROR, "IDAT without IHDR\n");
return AVERROR_INVALIDDATA;
}
if (!(s->pic_state & PNG_IDAT)) {
/* init image info */
ret = ff_set_dimensions(avctx, s->width, s->height);
if (ret < 0)
return ret;
s->channels = ff_png_get_nb_channels(s->color_type);
s->bits_per_pixel = s->bit_depth * s->channels;
s->bpp = (s->bits_per_pixel + 7) >> 3;
s->row_size = (s->cur_w * s->bits_per_pixel + 7) >> 3;
if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
s->color_type == PNG_COLOR_TYPE_RGB) {
avctx->pix_fmt = AV_PIX_FMT_RGB24;
} else if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
avctx->pix_fmt = AV_PIX_FMT_RGBA;
} else if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
s->color_type == PNG_COLOR_TYPE_GRAY) {
avctx->pix_fmt = AV_PIX_FMT_GRAY8;
} else if (s->bit_depth == 16 &&
s->color_type == PNG_COLOR_TYPE_GRAY) {
avctx->pix_fmt = AV_PIX_FMT_GRAY16BE;
} else if (s->bit_depth == 16 &&
s->color_type == PNG_COLOR_TYPE_RGB) {
avctx->pix_fmt = AV_PIX_FMT_RGB48BE;
} else if (s->bit_depth == 16 &&
s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
avctx->pix_fmt = AV_PIX_FMT_RGBA64BE;
} else if ((s->bits_per_pixel == 1 || s->bits_per_pixel == 2 || s->bits_per_pixel == 4 || s->bits_per_pixel == 8) &&
s->color_type == PNG_COLOR_TYPE_PALETTE) {
avctx->pix_fmt = avctx->codec_id == AV_CODEC_ID_APNG ? AV_PIX_FMT_RGBA : AV_PIX_FMT_PAL8;
} else if (s->bit_depth == 1 && s->bits_per_pixel == 1 && avctx->codec_id != AV_CODEC_ID_APNG) {
avctx->pix_fmt = AV_PIX_FMT_MONOBLACK;
} else if (s->bit_depth == 8 &&
s->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
avctx->pix_fmt = AV_PIX_FMT_YA8;
} else if (s->bit_depth == 16 &&
s->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
avctx->pix_fmt = AV_PIX_FMT_YA16BE;
} else {
avpriv_report_missing_feature(avctx,
"Bit depth %d color type %d",
s->bit_depth, s->color_type);
return AVERROR_PATCHWELCOME;
}
if (s->has_trns && s->color_type != PNG_COLOR_TYPE_PALETTE) {
switch (avctx->pix_fmt) {
case AV_PIX_FMT_RGB24:
avctx->pix_fmt = AV_PIX_FMT_RGBA;
break;
case AV_PIX_FMT_RGB48BE:
avctx->pix_fmt = AV_PIX_FMT_RGBA64BE;
break;
case AV_PIX_FMT_GRAY8:
avctx->pix_fmt = AV_PIX_FMT_YA8;
break;
case AV_PIX_FMT_GRAY16BE:
avctx->pix_fmt = AV_PIX_FMT_YA16BE;
break;
default:
avpriv_request_sample(avctx, "bit depth %d "
"and color type %d with TRNS",
s->bit_depth, s->color_type);
return AVERROR_INVALIDDATA;
}
s->bpp += byte_depth;
}
ff_thread_release_ext_buffer(avctx, &s->picture);
if (s->dispose_op == APNG_DISPOSE_OP_PREVIOUS) {
/* We only need a buffer for the current picture. */
ret = ff_thread_get_buffer(avctx, p, 0);
if (ret < 0)
return ret;
} else if (s->dispose_op == APNG_DISPOSE_OP_BACKGROUND) {
/* We need a buffer for the current picture as well as
* a buffer for the reference to retain. */
ret = ff_thread_get_ext_buffer(avctx, &s->picture,
AV_GET_BUFFER_FLAG_REF);
if (ret < 0)
return ret;
ret = ff_thread_get_buffer(avctx, p, 0);
if (ret < 0)
return ret;
} else {
/* The picture output this time and the reference to retain coincide. */
if ((ret = ff_thread_get_ext_buffer(avctx, &s->picture,
AV_GET_BUFFER_FLAG_REF)) < 0)
return ret;
ret = av_frame_ref(p, s->picture.f);
if (ret < 0)
return ret;
}
p->pict_type = AV_PICTURE_TYPE_I;
p->flags |= AV_FRAME_FLAG_KEY;
p->flags |= AV_FRAME_FLAG_INTERLACED * !!s->interlace_type;
if ((ret = populate_avctx_color_fields(avctx, p)) < 0)
return ret;
ff_thread_finish_setup(avctx);
/* compute the compressed row size */
if (!s->interlace_type) {
s->crow_size = s->row_size + 1;
} else {
s->pass = 0;
s->pass_row_size = ff_png_pass_row_size(s->pass,
s->bits_per_pixel,
s->cur_w);
s->crow_size = s->pass_row_size + 1;
}
ff_dlog(avctx, "row_size=%d crow_size =%d\n",
s->row_size, s->crow_size);
/* copy the palette if needed */
if (avctx->pix_fmt == AV_PIX_FMT_PAL8)
memcpy(p->data[1], s->palette, 256 * sizeof(uint32_t));
/* empty row is used if differencing to the first row */
av_fast_padded_mallocz(&s->last_row, &s->last_row_size, s->row_size);
if (!s->last_row)
return AVERROR_INVALIDDATA;
if (s->interlace_type ||
s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
av_fast_padded_malloc(&s->tmp_row, &s->tmp_row_size, s->row_size);
if (!s->tmp_row)
return AVERROR_INVALIDDATA;
}
/* compressed row */
av_fast_padded_malloc(&s->buffer, &s->buffer_size, s->row_size + 16);
if (!s->buffer)
return AVERROR(ENOMEM);
/* we want crow_buf+1 to be 16-byte aligned */
s->crow_buf = s->buffer + 15;
s->zstream.zstream.avail_out = s->crow_size;
s->zstream.zstream.next_out = s->crow_buf;
}
s->pic_state |= PNG_IDAT;
/* set image to non-transparent bpp while decompressing */
if (s->has_trns && s->color_type != PNG_COLOR_TYPE_PALETTE)
s->bpp -= byte_depth;
ret = png_decode_idat(s, gb, p->data[0], p->linesize[0]);
if (s->has_trns && s->color_type != PNG_COLOR_TYPE_PALETTE)
s->bpp += byte_depth;
if (ret < 0)
return ret;
return 0;
}
static int decode_plte_chunk(AVCodecContext *avctx, PNGDecContext *s,
GetByteContext *gb)
{
int length = bytestream2_get_bytes_left(gb);
int n, i, r, g, b;
if ((length % 3) != 0 || length > 256 * 3)
return AVERROR_INVALIDDATA;
/* read the palette */
n = length / 3;
for (i = 0; i < n; i++) {
r = bytestream2_get_byte(gb);
g = bytestream2_get_byte(gb);
b = bytestream2_get_byte(gb);
s->palette[i] = (0xFFU << 24) | (r << 16) | (g << 8) | b;
}
for (; i < 256; i++)
s->palette[i] = (0xFFU << 24);
s->hdr_state |= PNG_PLTE;
return 0;
}
static int decode_trns_chunk(AVCodecContext *avctx, PNGDecContext *s,
GetByteContext *gb)
{
int length = bytestream2_get_bytes_left(gb);
int v, i;
if (!(s->hdr_state & PNG_IHDR)) {
av_log(avctx, AV_LOG_ERROR, "trns before IHDR\n");
return AVERROR_INVALIDDATA;
}
if (s->pic_state & PNG_IDAT) {
av_log(avctx, AV_LOG_ERROR, "trns after IDAT\n");
return AVERROR_INVALIDDATA;
}
if (s->color_type == PNG_COLOR_TYPE_PALETTE) {
if (length > 256 || !(s->hdr_state & PNG_PLTE))
return AVERROR_INVALIDDATA;
for (i = 0; i < length; i++) {
unsigned v = bytestream2_get_byte(gb);
s->palette[i] = (s->palette[i] & 0x00ffffff) | (v << 24);
}
} else if (s->color_type == PNG_COLOR_TYPE_GRAY || s->color_type == PNG_COLOR_TYPE_RGB) {
if ((s->color_type == PNG_COLOR_TYPE_GRAY && length != 2) ||
(s->color_type == PNG_COLOR_TYPE_RGB && length != 6) ||
s->bit_depth == 1)
return AVERROR_INVALIDDATA;
for (i = 0; i < length / 2; i++) {
/* only use the least significant bits */
v = av_mod_uintp2(bytestream2_get_be16(gb), s->bit_depth);
if (s->bit_depth > 8)
AV_WB16(&s->transparent_color_be[2 * i], v);
else
s->transparent_color_be[i] = v;
}
} else {
return AVERROR_INVALIDDATA;
}
s->has_trns = 1;
return 0;
}
static int decode_iccp_chunk(PNGDecContext *s, GetByteContext *gb)
{
int ret, cnt = 0;
AVBPrint bp;
while ((s->iccp_name[cnt++] = bytestream2_get_byte(gb)) && cnt < 81);
if (cnt > 80) {
av_log(s->avctx, AV_LOG_ERROR, "iCCP with invalid name!\n");
ret = AVERROR_INVALIDDATA;
goto fail;
}
if (bytestream2_get_byte(gb) != 0) {
av_log(s->avctx, AV_LOG_ERROR, "iCCP with invalid compression!\n");
ret = AVERROR_INVALIDDATA;
goto fail;
}
if ((ret = decode_zbuf(&bp, gb->buffer, gb->buffer_end, s->avctx)) < 0)
return ret;
av_freep(&s->iccp_data);
ret = av_bprint_finalize(&bp, (char **)&s->iccp_data);
if (ret < 0)