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| author | Michael Niedermayer <michaelni@gmx.at> | 2010-10-21 22:44:41 +0000 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2010-10-21 22:44:41 +0000 |
| commit | 5675a11f9277b5c7b1c9ad45da893e9ef9a42f03 (patch) | |
| tree | 6c6c4ee0d9c3b3a5d7de140ab0a83bde348d804a /libavcodec/mjpegdec.c | |
| parent | 8870b2514054f50ce35a6d6717dd44db6595e764 (diff) | |
| download | ffmpeg-5675a11f9277b5c7b1c9ad45da893e9ef9a42f03.tar.gz | |
Add a seperate VLC table for progressive jpeg so we dont have to subtract 16 in the inner loop.
Originally committed as revision 25545 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/mjpegdec.c')
| -rw-r--r-- | libavcodec/mjpegdec.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c index 7d1aa530e2..ec798594f4 100644 --- a/libavcodec/mjpegdec.c +++ b/libavcodec/mjpegdec.c @@ -69,6 +69,10 @@ static void build_basic_mjpeg_vlc(MJpegDecodeContext * s) { ff_mjpeg_val_ac_luminance, 251, 0, 1); build_vlc(&s->vlcs[1][1], ff_mjpeg_bits_ac_chrominance, ff_mjpeg_val_ac_chrominance, 251, 0, 1); + build_vlc(&s->vlcs[2][0], ff_mjpeg_bits_ac_luminance, + ff_mjpeg_val_ac_luminance, 251, 0, 0); + build_vlc(&s->vlcs[2][1], ff_mjpeg_bits_ac_chrominance, + ff_mjpeg_val_ac_chrominance, 251, 0, 0); } av_cold int ff_mjpeg_decode_init(AVCodecContext *avctx) @@ -188,6 +192,9 @@ int ff_mjpeg_decode_dht(MJpegDecodeContext *s) if(build_vlc(&s->vlcs[class][index], bits_table, val_table, code_max + 1, 0, class > 0) < 0){ return -1; } + if(class>0 && build_vlc(&s->vlcs[2][index], bits_table, val_table, code_max + 1, 0, 0) < 0){ + return -1; + } } return 0; } @@ -473,9 +480,8 @@ static int decode_block_progressive(MJpegDecodeContext *s, DCTELEM *block, uint8 {OPEN_READER(re, &s->gb) for(i=ss;;i++) { UPDATE_CACHE(re, &s->gb); - GET_VLC(code, re, &s->gb, s->vlcs[1][ac_index].table, 9, 2) - /* Progressive JPEG use AC coeffs from zero and this decoder sets offset 16 by default */ - code -= 16; + GET_VLC(code, re, &s->gb, s->vlcs[2][ac_index].table, 9, 2) + run = ((unsigned) code) >> 4; code &= 0xF; if(code) { @@ -561,9 +567,8 @@ static int decode_block_refinement(MJpegDecodeContext *s, DCTELEM *block, uint8_ else { for(;;i++) { UPDATE_CACHE(re, &s->gb); - GET_VLC(code, re, &s->gb, s->vlcs[1][ac_index].table, 9, 2) - /* Progressive JPEG use AC coeffs from zero and this decoder sets offset 16 by default */ - code -= 16; + GET_VLC(code, re, &s->gb, s->vlcs[2][ac_index].table, 9, 2) + if(code & 0xF) { run = ((unsigned) code) >> 4; UPDATE_CACHE(re, &s->gb); |