diff --git a/libavcodec/vc1.c b/libavcodec/vc1.c index 719c28d746..25e3579d5c 100644 --- a/libavcodec/vc1.c +++ b/libavcodec/vc1.c @@ -1138,9 +1138,14 @@ int ff_vc1_parse_frame_header_adv(VC1Context *v, GetBitContext* gb) } break; case AV_PICTURE_TYPE_B: - // TODO: implement interlaced frame B picture decoding - if (v->fcm == ILACE_FRAME) - return -1; + if (v->fcm == ILACE_FRAME) { + v->bfraction_lut_index = get_vlc2(gb, ff_vc1_bfraction_vlc.table, VC1_BFRACTION_VLC_BITS, 1); + v->bfraction = ff_vc1_bfraction_lut[v->bfraction_lut_index]; + if (v->bfraction == 0) { + return -1; + } + return -1; // This codepath is still incomplete thus it is disabled + } if (v->extended_mv) v->mvrange = get_unary(gb, 0, 3); else @@ -1186,6 +1191,38 @@ int ff_vc1_parse_frame_header_adv(VC1Context *v, GetBitContext* gb) v->fourmvbp_vlc = &ff_vc1_4mv_block_pattern_vlc[fourmvbptab]; } v->numref = 1; // interlaced field B pictures are always 2-ref + } else if (v->fcm == ILACE_FRAME) { + if (v->extended_dmv) + v->dmvrange = get_unary(gb, 0, 3); + if (get_bits1(gb)) /* intcomp - present but shall always be 0 */ + av_log(v->s.avctx, AV_LOG_WARNING, "Intensity compensation set for B picture\n"); + v->intcomp = 0; + v->mv_mode = MV_PMODE_1MV; + v->fourmvswitch = 0; + v->qs_last = v->s.quarter_sample; + v->s.quarter_sample = 1; + v->s.mspel = 1; + status = bitplane_decoding(v->direct_mb_plane, &v->dmb_is_raw, v); + if (status < 0) + return -1; + av_log(v->s.avctx, AV_LOG_DEBUG, "MB Direct Type plane encoding: " + "Imode: %i, Invert: %i\n", status>>1, status&1); + status = bitplane_decoding(v->s.mbskip_table, &v->skip_is_raw, v); + if (status < 0) + return -1; + av_log(v->s.avctx, AV_LOG_DEBUG, "MB Skip plane encoding: " + "Imode: %i, Invert: %i\n", status>>1, status&1); + mbmodetab = get_bits(gb, 2); + v->mbmode_vlc = &ff_vc1_intfr_non4mv_mbmode_vlc[mbmodetab]; + imvtab = get_bits(gb, 2); + v->imv_vlc = &ff_vc1_1ref_mvdata_vlc[imvtab]; + // interlaced p/b-picture cbpcy range is [1, 63] + icbptab = get_bits(gb, 3); + v->cbpcy_vlc = &ff_vc1_icbpcy_vlc[icbptab]; + twomvbptab = get_bits(gb, 2); + v->twomvbp_vlc = &ff_vc1_2mv_block_pattern_vlc[twomvbptab]; + fourmvbptab = get_bits(gb, 2); + v->fourmvbp_vlc = &ff_vc1_4mv_block_pattern_vlc[fourmvbptab]; } else { v->mv_mode = get_bits1(gb) ? MV_PMODE_1MV : MV_PMODE_1MV_HPEL_BILIN; v->qs_last = v->s.quarter_sample;