diff options
| author | Ronald S. Bultje <rsbultje@gmail.com> | 2012-10-04 09:01:45 +0200 |
|---|---|---|
| committer | Clément Bœsch <ubitux@gmail.com> | 2012-10-05 07:35:58 +0200 |
| commit | 2e59210edfe822cce1369dd962d791cc9d45798b (patch) | |
| tree | f7732535b6196830265b14ec87d6d67469b84478 /libavcodec/h264_cavlc.c | |
| parent | 5cdd3b995c9dd79ab6ab852a27e75a21c0eb4f5f (diff) | |
| download | ffmpeg-2e59210edfe822cce1369dd962d791cc9d45798b.tar.gz | |
lavc/h264: don't touch H264Context->ref_count[] during MB decoding.
The variable is copied to subsequent threads at the same time, so this
may cause wrong ref_count[] values to be copied to subsequent threads.
This bug was found using TSAN and Helgrind.
Original patch by Ronald, adapted with a local_ref_count by Clément,
following the suggestion of Michael Niedermayer.
Signed-off-by: Clément Bœsch <clement.boesch@smartjog.com>
Diffstat (limited to 'libavcodec/h264_cavlc.c')
| -rw-r--r-- | libavcodec/h264_cavlc.c | 32 |
1 files changed, 13 insertions, 19 deletions
diff --git a/libavcodec/h264_cavlc.c b/libavcodec/h264_cavlc.c index f5d403b762..6dfe2474cc 100644 --- a/libavcodec/h264_cavlc.c +++ b/libavcodec/h264_cavlc.c @@ -700,6 +700,7 @@ int ff_h264_decode_mb_cavlc(H264Context *h){ int dct8x8_allowed= h->pps.transform_8x8_mode; int decode_chroma = h->sps.chroma_format_idc == 1 || h->sps.chroma_format_idc == 2; const int pixel_shift = h->pixel_shift; + unsigned local_ref_count[2]; mb_xy = h->mb_xy = s->mb_x + s->mb_y*s->mb_stride; @@ -785,10 +786,8 @@ decode_intra_mb: return 0; } - if(MB_MBAFF){ - h->ref_count[0] <<= 1; - h->ref_count[1] <<= 1; - } + local_ref_count[0] = h->ref_count[0] << MB_MBAFF; + local_ref_count[1] = h->ref_count[1] << MB_MBAFF; fill_decode_neighbors(h, mb_type); fill_decode_caches(h, mb_type); @@ -869,7 +868,7 @@ decode_intra_mb: } for(list=0; list<h->list_count; list++){ - int ref_count= IS_REF0(mb_type) ? 1 : h->ref_count[list]; + int ref_count= IS_REF0(mb_type) ? 1 : local_ref_count[list]; for(i=0; i<4; i++){ if(IS_DIRECT(h->sub_mb_type[i])) continue; if(IS_DIR(h->sub_mb_type[i], 0, list)){ @@ -949,13 +948,13 @@ decode_intra_mb: for(list=0; list<h->list_count; list++){ unsigned int val; if(IS_DIR(mb_type, 0, list)){ - if(h->ref_count[list]==1){ + if(local_ref_count[list]==1){ val= 0; - }else if(h->ref_count[list]==2){ + }else if(local_ref_count[list]==2){ val= get_bits1(&s->gb)^1; }else{ val= get_ue_golomb_31(&s->gb); - if(val >= h->ref_count[list]){ + if(val >= local_ref_count[list]){ av_log(h->s.avctx, AV_LOG_ERROR, "ref %u overflow\n", val); return -1; } @@ -979,13 +978,13 @@ decode_intra_mb: for(i=0; i<2; i++){ unsigned int val; if(IS_DIR(mb_type, i, list)){ - if(h->ref_count[list] == 1){ + if(local_ref_count[list] == 1){ val= 0; - }else if(h->ref_count[list] == 2){ + }else if(local_ref_count[list] == 2){ val= get_bits1(&s->gb)^1; }else{ val= get_ue_golomb_31(&s->gb); - if(val >= h->ref_count[list]){ + if(val >= local_ref_count[list]){ av_log(h->s.avctx, AV_LOG_ERROR, "ref %u overflow\n", val); return -1; } @@ -1016,13 +1015,13 @@ decode_intra_mb: for(i=0; i<2; i++){ unsigned int val; if(IS_DIR(mb_type, i, list)){ //FIXME optimize - if(h->ref_count[list]==1){ + if(local_ref_count[list]==1){ val= 0; - }else if(h->ref_count[list]==2){ + }else if(local_ref_count[list]==2){ val= get_bits1(&s->gb)^1; }else{ val= get_ue_golomb_31(&s->gb); - if(val >= h->ref_count[list]){ + if(val >= local_ref_count[list]){ av_log(h->s.avctx, AV_LOG_ERROR, "ref %u overflow\n", val); return -1; } @@ -1162,10 +1161,5 @@ decode_intra_mb: s->current_picture.f.qscale_table[mb_xy] = s->qscale; write_back_non_zero_count(h); - if(MB_MBAFF){ - h->ref_count[0] >>= 1; - h->ref_count[1] >>= 1; - } - return 0; } |