s->fake_picture_number++;
void mpeg1_encode_picture_header(MpegEncContext *s, int picture_number){    static int done=0;    if (!done) {	int i;        done = 1;        init_rl(&rl_mpeg1);		for(i=0; i<64; i++)	{		mpeg1_max_level[0][i]= rl_mpeg1.max_level[0][i];		mpeg1_index_run[0][i]= rl_mpeg1.index_run[0][i];	}	/* build unified dc encoding tables */	for(i=-255; i<256; i++)	{		int adiff, index;		int bits, code;		int diff=i;		adiff = ABS(diff);		if(diff<0) diff--;		index = vlc_dc_table[adiff];		bits= vlc_dc_lum_bits[index] + index;		code= (vlc_dc_lum_code[index]<<index) + (diff & ((1 << index) - 1));		mpeg1_lum_dc_uni[i+255]= bits + (code<<8);				bits= vlc_dc_chroma_bits[index] + index;		code= (vlc_dc_chroma_code[index]<<index) + (diff & ((1 << index) - 1));		mpeg1_chr_dc_uni[i+255]= bits + (code<<8);	}    }    mpeg1_encode_sequence_header(s);    /* mpeg1 picture header */    put_header(s, PICTURE_START_CODE);    /* temporal reference */    put_bits(&s->pb, 10, (s->fake_picture_number -                           s->gop_picture_number) & 0x3ff);         put_bits(&s->pb, 3, s->pict_type);    put_bits(&s->pb, 16, 0xffff); /* non constant bit rate */        if (s->pict_type == P_TYPE) {        put_bits(&s->pb, 1, 0); /* half pel coordinates */        put_bits(&s->pb, 3, s->f_code); /* forward_f_code */    }        put_bits(&s->pb, 1, 0); /* extra bit picture */        /* only one slice */    put_header(s, SLICE_MIN_START_CODE);    put_bits(&s->pb, 5, s->qscale); /* quantizer scale */    put_bits(&s->pb, 1, 0); /* slice extra information */}