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avcodec/pngdec: create a function to decode IHDR chunk.

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Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Benoit Fouet 2014-11-14 10:17:31 +01:00 committed by Michael Niedermayer
parent 98abb98cb1
commit 1523d1484d
1 changed files with 28 additions and 20 deletions
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48
libavcodec/pngdec.c
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@ -519,6 +519,33 @@ static int decode_text_chunk(PNGDecContext *s, uint32_t length, int compressed,
return 0;
}
static int decode_ihdr_chunk(AVCodecContext *avctx, PNGDecContext *s,
uint32_t length)
{
if (length != 13)
return AVERROR_INVALIDDATA;
s->width = bytestream2_get_be32(&s->gb);
s->height = bytestream2_get_be32(&s->gb);
if (av_image_check_size(s->width, s->height, 0, avctx)) {
s->width = s->height = 0;
av_log(avctx, AV_LOG_ERROR, "Invalid image size\n");
return AVERROR_INVALIDDATA;
}
s->bit_depth = bytestream2_get_byte(&s->gb);
s->color_type = bytestream2_get_byte(&s->gb);
s->compression_type = bytestream2_get_byte(&s->gb);
s->filter_type = bytestream2_get_byte(&s->gb);
s->interlace_type = bytestream2_get_byte(&s->gb);
bytestream2_skip(&s->gb, 4); /* crc */
s->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;
}
static int decode_frame_png(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
@ -580,27 +607,8 @@ static int decode_frame_png(AVCodecContext *avctx,
((tag >> 24) & 0xff), length);
switch (tag) {
case MKTAG('I', 'H', 'D', 'R'):
if (length != 13)
if (decode_ihdr_chunk(avctx, s, length) < 0)
goto fail;
s->width = bytestream2_get_be32(&s->gb);
s->height = bytestream2_get_be32(&s->gb);
if (av_image_check_size(s->width, s->height, 0, avctx)) {
s->width = s->height = 0;
av_log(avctx, AV_LOG_ERROR, "Invalid image size\n");
goto fail;
}
s->bit_depth = bytestream2_get_byte(&s->gb);
s->color_type = bytestream2_get_byte(&s->gb);
s->compression_type = bytestream2_get_byte(&s->gb);
s->filter_type = bytestream2_get_byte(&s->gb);
s->interlace_type = bytestream2_get_byte(&s->gb);
bytestream2_skip(&s->gb, 4); /* crc */
s->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);
break;
case MKTAG('p', 'H', 'Y', 's'):
if (s->state & PNG_IDAT) {