ffmpeg | branch: master | Benoit Fouet <benoit.fo...@free.fr> | Fri Nov 14 10:17:35 2014 +0100| [6499e63f7b9e73d5b6b601f25803f9244de99bf6] | committer: Michael Niedermayer
avcodec/pngdec: create a function to decode tRNS chunk. Signed-off-by: Michael Niedermayer <michae...@gmx.at> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=6499e63f7b9e73d5b6b601f25803f9244de99bf6 --- libavcodec/pngdec.c | 33 ++++++++++++++++++++------------- 1 file changed, 20 insertions(+), 13 deletions(-) diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c index 9b5d5dd..92ed59d 100644 --- a/libavcodec/pngdec.c +++ b/libavcodec/pngdec.c @@ -694,6 +694,25 @@ static int decode_plte_chunk(AVCodecContext *avctx, PNGDecContext *s, return 0; } +static int decode_trns_chunk(AVCodecContext *avctx, PNGDecContext *s, + uint32_t length) +{ + int v, i; + + /* read the transparency. XXX: Only palette mode supported */ + if (s->color_type != PNG_COLOR_TYPE_PALETTE || + length > 256 || + !(s->state & PNG_PLTE)) + return AVERROR_INVALIDDATA; + for (i = 0; i < length; i++) { + v = bytestream2_get_byte(&s->gb); + s->palette[i] = (s->palette[i] & 0x00ffffff) | (v << 24); + } + bytestream2_skip(&s->gb, 4); /* crc */ + + return 0; +} + static int decode_frame_png(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt) @@ -771,20 +790,8 @@ static int decode_frame_png(AVCodecContext *avctx, goto skip_tag; break; case MKTAG('t', 'R', 'N', 'S'): - { - int v, i; - - /* read the transparency. XXX: Only palette mode supported */ - if (s->color_type != PNG_COLOR_TYPE_PALETTE || - length > 256 || - !(s->state & PNG_PLTE)) + if (decode_trns_chunk(avctx, s, length) < 0) goto skip_tag; - for (i = 0; i < length; i++) { - v = bytestream2_get_byte(&s->gb); - s->palette[i] = (s->palette[i] & 0x00ffffff) | (v << 24); - } - bytestream2_skip(&s->gb, 4); /* crc */ - } break; case MKTAG('t', 'E', 'X', 't'): if (decode_text_chunk(s, length, 0, &metadata) < 0) _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog
