static int mpeg_decode_slice(Mpeg1Context *s1, int mb_y, const uint8_t **buf, int buf_size) { MpegEncContext *s = &s1->mpeg_enc_ctx; AVCodecContext *avctx= s->avctx; int ret; const int field_pic= s->picture_structure != PICT_FRAME; s->resync_mb_x= s->resync_mb_y= -1; if (mb_y >= s->mb_height){ av_log(s->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", s->mb_y, s->mb_height); return -1; } init_get_bits(&s->gb, *buf, buf_size*8); ff_mpeg1_clean_buffers(s); s->interlaced_dct = 0; s->qscale = get_qscale(s); if(s->qscale == 0){ av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n"); return -1; } /* extra slice info */ while (get_bits1(&s->gb) != 0) { skip_bits(&s->gb, 8); } s->mb_x=0; for(;;) { int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2); if (code < 0){ av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n"); return -1; } if (code >= 33) { if (code == 33) { s->mb_x += 33; } /* otherwise, stuffing, nothing to do */ } else { s->mb_x += code; break; } } s->resync_mb_x= s->mb_x; s->resync_mb_y= s->mb_y= mb_y; s->mb_skip_run= 0; ff_init_block_index(s); if (s->mb_y==0 && s->mb_x==0 && (s->first_field || s->picture_structure==PICT_FRAME)) { if(s->avctx->debug&FF_DEBUG_PICT_INFO){ av_log(s->avctx, AV_LOG_DEBUG, "qp:%d fc:%2d%2d%2d%2d %s %s %s %s %s dc:%d pstruct:%d fdct:%d cmv:%d qtype:%d ivlc:%d rff:%d %s\n", s->qscale, s->mpeg_f_code[0][0],s->mpeg_f_code[0][1],s->mpeg_f_code[1][0],s->mpeg_f_code[1][1], s->pict_type == I_TYPE ? "I" : (s->pict_type == P_TYPE ? "P" : (s->pict_type == B_TYPE ? "B" : "S")), s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"", s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors, s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :""); } } for(;;) { #ifdef HAVE_XVMC //one 1 we memcpy blocks in xvmcvideo if(s->avctx->xvmc_acceleration > 1) XVMC_init_block(s);//set s->block #endif s->dsp.clear_blocks(s->block[0]); ret = mpeg_decode_mb(s, s->block); s->chroma_qscale= s->qscale; dprintf("ret=%d\n", ret); if (ret < 0) return -1; if(s->current_picture.motion_val[0] && !s->encoding){ //note motion_val is normally NULL unless we want to extract the MVs const int wrap = field_pic ? 2*s->b8_stride : s->b8_stride; int xy = s->mb_x*2 + s->mb_y*2*wrap; int motion_x, motion_y, dir, i; if(field_pic && !s->first_field) xy += wrap/2; for(i=0; i<2; i++){ for(dir=0; dir<2; dir++){ if (s->mb_intra || (dir==1 && s->pict_type != B_TYPE)) { motion_x = motion_y = 0; }else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)){ motion_x = s->mv[dir][0][0]; motion_y = s->mv[dir][0][1]; } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ { motion_x = s->mv[dir][i][0]; motion_y = s->mv[dir][i][1]; } s->current_picture.motion_val[dir][xy ][0] = motion_x; s->current_picture.motion_val[dir][xy ][1] = motion_y; s->current_picture.motion_val[dir][xy + 1][0] = motion_x; s->current_picture.motion_val[dir][xy + 1][1] = motion_y; s->current_picture.ref_index [dir][xy ]= s->current_picture.ref_index [dir][xy + 1]= s->field_select[dir][i]; } xy += wrap; } } s->dest[0] += 16; s->dest[1] += 8; s->dest[2] += 8; MPV_decode_mb(s, s->block); if (++s->mb_x >= s->mb_width) { ff_draw_horiz_band(s, 16*s->mb_y, 16); s->mb_x = 0; s->mb_y++; if(s->mb_y<<field_pic >= s->mb_height){ int left= s->gb.size_in_bits - get_bits_count(&s->gb); if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23))) || (avctx->error_resilience >= FF_ER_AGGRESSIVE && left>8)){ av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d\n", left); return -1; }else goto eos; } ff_init_block_index(s); } /* skip mb handling */ if (s->mb_skip_run == -1) { /* read again increment */ s->mb_skip_run = 0; for(;;) { int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2); if (code < 0){ av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n"); return -1; } if (code >= 33) { if (code == 33) { s->mb_skip_run += 33; }else if(code == 35){ if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){ av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n"); return -1; } goto eos; /* end of slice */ } /* otherwise, stuffing, nothing to do */ } else { s->mb_skip_run += code; break; } } } } eos: // end of slice *buf += get_bits_count(&s->gb)/8 - 1; //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y); return 0; }