static void encode_seq_header(VC2EncContext *s)
{
    avpriv_align_put_bits(&s->pb);
    encode_parse_params(s);
    put_vc2_ue_uint(&s->pb, s->base_vf);
    encode_source_params(s);
    put_vc2_ue_uint(&s->pb, s->interlaced); /* Frames or fields coding */
}
static void encode_seq_header(VC2EncContext *s)
{
    avpriv_align_put_bits(&s->pb);
    encode_parse_params(s);
    put_vc2_ue_uint(&s->pb, s->base_vf);
    encode_source_params(s);
    put_vc2_ue_uint(&s->pb, s->interlaced);  
}