static int decode_slice(MpegEncContext *s){ const int part_mask= s->partitioned_frame ? (ER_AC_END|ER_AC_ERROR) : 0x7F; const int mb_size= 16>>s->avctx->lowres; int ret; s->last_resync_gb= s->gb; s->first_slice_line= 1; s->resync_mb_x= s->mb_x; s->resync_mb_y= s->mb_y; ff_set_qscale(s, s->qscale); if (s->avctx->hwaccel) { const uint8_t *start= s->gb.buffer + get_bits_count(&s->gb)/8; const uint8_t *end = ff_h263_find_resync_marker(start + 1, s->gb.buffer_end); skip_bits_long(&s->gb, 8*(end - start)); return s->avctx->hwaccel->decode_slice(s->avctx, start, end - start); } if(s->partitioned_frame){ const int qscale= s->qscale; if(CONFIG_MPEG4_DECODER && s->codec_id==AV_CODEC_ID_MPEG4){ if ((ret = ff_mpeg4_decode_partitions(s)) < 0) return ret; } /* restore variables which were modified */ s->first_slice_line=1; s->mb_x= s->resync_mb_x; s->mb_y= s->resync_mb_y; ff_set_qscale(s, qscale); } for(; s->mb_y < s->mb_height; s->mb_y++) { /* per-row end of slice checks */ if(s->msmpeg4_version){ if(s->resync_mb_y + s->slice_height == s->mb_y){ ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_MB_END); return 0; } } if(s->msmpeg4_version==1){ s->last_dc[0]= s->last_dc[1]= s->last_dc[2]= 128; } ff_init_block_index(s); for(; s->mb_x < s->mb_width; s->mb_x++) { int ret; ff_update_block_index(s); if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){ s->first_slice_line=0; } /* DCT & quantize */ s->mv_dir = MV_DIR_FORWARD; s->mv_type = MV_TYPE_16X16; // s->mb_skipped = 0; av_dlog(s, "%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24)); ret= s->decode_mb(s, s->block); if (s->pict_type!=AV_PICTURE_TYPE_B) ff_h263_update_motion_val(s); if(ret<0){ const int xy= s->mb_x + s->mb_y*s->mb_stride; if(ret==SLICE_END){ ff_MPV_decode_mb(s, s->block); if(s->loop_filter) ff_h263_loop_filter(s); ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_END&part_mask); s->padding_bug_score--; if(++s->mb_x >= s->mb_width){ s->mb_x=0; ff_draw_horiz_band(s, s->mb_y*mb_size, mb_size); ff_MPV_report_decode_progress(s); s->mb_y++; } return 0; }else if(ret==SLICE_NOEND){ av_log(s->avctx, AV_LOG_ERROR, "Slice mismatch at MB: %d\n", xy); ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x+1, s->mb_y, ER_MB_END&part_mask); return AVERROR_INVALIDDATA; } av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", xy); ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_ERROR&part_mask); return AVERROR_INVALIDDATA; } ff_MPV_decode_mb(s, s->block); if(s->loop_filter) ff_h263_loop_filter(s); } ff_draw_horiz_band(s, s->mb_y*mb_size, mb_size); ff_MPV_report_decode_progress(s); s->mb_x= 0; } assert(s->mb_x==0 && s->mb_y==s->mb_height); if(s->codec_id==AV_CODEC_ID_MPEG4 && (s->workaround_bugs&FF_BUG_AUTODETECT) && get_bits_left(&s->gb) >= 48 && show_bits(&s->gb, 24)==0x4010 && !s->data_partitioning) s->padding_bug_score+=32; /* try to detect the padding bug */ if( s->codec_id==AV_CODEC_ID_MPEG4 && (s->workaround_bugs&FF_BUG_AUTODETECT) && get_bits_left(&s->gb) >=0 && get_bits_left(&s->gb) < 137 // && !s->resync_marker && !s->data_partitioning){ const int bits_count= get_bits_count(&s->gb); const int bits_left = s->gb.size_in_bits - bits_count; if(bits_left==0){ s->padding_bug_score+=16; } else if(bits_left != 1){ int v= show_bits(&s->gb, 8); v|= 0x7F >> (7-(bits_count&7)); if(v==0x7F && bits_left<=8) s->padding_bug_score--; else if(v==0x7F && ((get_bits_count(&s->gb)+8)&8) && bits_left<=16) s->padding_bug_score+= 4; else s->padding_bug_score++; } } if(s->workaround_bugs&FF_BUG_AUTODETECT){ if(s->padding_bug_score > -2 && !s->data_partitioning /*&& (s->divx_version>=0 || !s->resync_marker)*/) s->workaround_bugs |= FF_BUG_NO_PADDING; else s->workaround_bugs &= ~FF_BUG_NO_PADDING; } // handle formats which don't have unique end markers if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly int left= get_bits_left(&s->gb); int max_extra=7; /* no markers in M$ crap */ if(s->msmpeg4_version && s->pict_type==AV_PICTURE_TYPE_I) max_extra+= 17; /* buggy padding but the frame should still end approximately at the bitstream end */ if((s->workaround_bugs&FF_BUG_NO_PADDING) && (s->err_recognition&(AV_EF_BUFFER|AV_EF_AGGRESSIVE))) max_extra+= 48; else if((s->workaround_bugs&FF_BUG_NO_PADDING)) max_extra+= 256*256*256*64; if(left>max_extra){ av_log(s->avctx, AV_LOG_ERROR, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24)); } else if(left<0){ av_log(s->avctx, AV_LOG_ERROR, "overreading %d bits\n", -left); }else ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_MB_END); return 0; } av_log(s->avctx, AV_LOG_ERROR, "slice end not reached but screenspace end (%d left %06X, score= %d)\n", get_bits_left(&s->gb), show_bits(&s->gb, 24), s->padding_bug_score); ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_END&part_mask); return AVERROR_INVALIDDATA; }