static void encode_picture_header(VC2EncContext *s)
{
    avpriv_align_put_bits(&s->pb);
    put_bits32(&s->pb, s->picture_number++);
}
static void encode_picture_header(VC2EncContext *s)
{
    avpriv_align_put_bits(&s->pb);
    put_bits32(&s->pb, s->picture_number++);
}