- if (avctx->hwaccel->start_frame(avctx, buf, buf_size) < 0)
- goto err;
- if (avctx->hwaccel->decode_slice(avctx, buf_start, (buf + buf_size) - buf_start) < 0)
- goto err;
- if (avctx->hwaccel->end_frame(avctx) < 0)
- goto err;
+ if (v->field_mode && buf_start_second_field) {
+ // decode first field
+ s->picture_structure = PICT_BOTTOM_FIELD - v->tff;
+ if (avctx->hwaccel->start_frame(avctx, buf_start, buf_start_second_field - buf_start) < 0)
+ goto err;
+ if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_start_second_field - buf_start) < 0)
+ goto err;
+ if (avctx->hwaccel->end_frame(avctx) < 0)
+ goto err;
+
+ // decode second field
+ s->gb = slices[n_slices1 + 1].gb;
+ s->picture_structure = PICT_TOP_FIELD + v->tff;
+ v->second_field = 1;
+ v->pic_header_flag = 0;
+ if (ff_vc1_parse_frame_header_adv(v, &s->gb) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "parsing header for second field failed");
+ goto err;
+ }
+ v->s.current_picture_ptr->f.pict_type = v->s.pict_type;
+
+ if (avctx->hwaccel->start_frame(avctx, buf_start_second_field, (buf + buf_size) - buf_start_second_field) < 0)
+ goto err;
+ if (avctx->hwaccel->decode_slice(avctx, buf_start_second_field, (buf + buf_size) - buf_start_second_field) < 0)
+ goto err;
+ if (avctx->hwaccel->end_frame(avctx) < 0)
+ goto err;
+ } else {
+ s->picture_structure = PICT_FRAME;
+ if (avctx->hwaccel->start_frame(avctx, buf_start, (buf + buf_size) - buf_start) < 0)
+ goto err;
+ if (avctx->hwaccel->decode_slice(avctx, buf_start, (buf + buf_size) - buf_start) < 0)
+ goto err;
+ if (avctx->hwaccel->end_frame(avctx) < 0)
+ goto err;
+ }