s->no_rounding=0;
void mpeg4_encode_picture_header(MpegEncContext * s, int picture_number){    int time_incr;    int time_div, time_mod;        if(s->pict_type==I_TYPE){        s->no_rounding=0;        if(picture_number==0 || !s->strict_std_compliance)            mpeg4_encode_vol_header(s);    }        s->partitioned_frame= s->data_partitioning && s->pict_type!=B_TYPE;//printf("num:%d rate:%d base:%d\n", s->picture_number, s->frame_rate, FRAME_RATE_BASE);        put_bits(&s->pb, 16, 0);	        /* vop header */    put_bits(&s->pb, 16, 0x1B6);	/* vop header */    put_bits(&s->pb, 2, s->pict_type - 1);	/* pict type: I = 0 , P = 1 */    time_div= s->time/s->time_increment_resolution;    time_mod= s->time%s->time_increment_resolution;    time_incr= time_div - s->last_time_base;    while(time_incr--)        put_bits(&s->pb, 1, 1);            put_bits(&s->pb, 1, 0);    put_bits(&s->pb, 1, 1);	/* marker */    put_bits(&s->pb, s->time_increment_bits, time_mod);	/* time increment */    put_bits(&s->pb, 1, 1);	/* marker */    put_bits(&s->pb, 1, 1);	/* vop coded */    if (    s->pict_type == P_TYPE         || (s->pict_type == S_TYPE && s->vol_sprite_usage==GMC_SPRITE)) {        s->no_rounding ^= 1;	put_bits(&s->pb, 1, s->no_rounding);	/* rounding type */    }    put_bits(&s->pb, 3, 0);	/* intra dc VLC threshold */    if(!s->progressive_sequence){         put_bits(&s->pb, 1, s->top_field_first);         put_bits(&s->pb, 1, s->alternate_scan);    }    //FIXME sprite stuff    put_bits(&s->pb, 5, s->qscale);    if (s->pict_type != I_TYPE)	put_bits(&s->pb, 3, s->f_code);	/* fcode_for */    if (s->pict_type == B_TYPE)	put_bits(&s->pb, 3, s->b_code);	/* fcode_back */    //    printf("****frame %d\n", picture_number);     s->y_dc_scale_table= ff_mpeg4_y_dc_scale_table; //FIXME add short header support      s->c_dc_scale_table= ff_mpeg4_c_dc_scale_table;     s->h_edge_pos= s->width;     s->v_edge_pos= s->height;}