avctx->has_b_frames= s->has_b_frames=1;
avctx->has_b_frames= 1;
static int svq1_decode_init(AVCodecContext *avctx){    MpegEncContext *s = avctx->priv_data;    s->avctx = avctx;    s->width = (avctx->width+3)&~3;    s->height = (avctx->height+3)&~3;    s->codec_id= avctx->codec->id;    avctx->pix_fmt = PIX_FMT_YUV410P;    avctx->has_b_frames= s->has_b_frames=1; // not true, but DP frames and these behave like unidirectional b frames    s->flags= avctx->flags;    if (MPV_common_init(s) < 0) return -1;    return 0;}