msmpeg4.c

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        put_bits(&s->pb, 6, my);
    }
}

static inline void handle_slices(MpegEncContext *s){
    if (s->mb_x == 0) {
        if (s->slice_height && (s->mb_y % s->slice_height) == 0) {
            if(s->msmpeg4_version != 4){
                ff_mpeg4_clean_buffers(s);
            }
            s->first_slice_line = 1;
        } else {
            s->first_slice_line = 0; 
        }
    }
}

void msmpeg4_encode_mb(MpegEncContext * s, 
                       DCTELEM block[6][64],
                       int motion_x, int motion_y)
{
    int cbp, coded_cbp, i;
    int pred_x, pred_y;
    UINT8 *coded_block;

    handle_slices(s);
    
    if (!s->mb_intra) {
	/* compute cbp */
        set_stat(ST_INTER_MB);
	cbp = 0;
	for (i = 0; i < 6; i++) {
	    if (s->block_last_index[i] >= 0)
		cbp |= 1 << (5 - i);
	}
	if (s->use_skip_mb_code && (cbp | motion_x | motion_y) == 0) {
	    /* skip macroblock */
	    put_bits(&s->pb, 1, 1);
	    return;
	}
        if (s->use_skip_mb_code)
            put_bits(&s->pb, 1, 0);	/* mb coded */
        
        if(s->msmpeg4_version<=2){
            put_bits(&s->pb, 
                     v2_mb_type[cbp&3][1], 
                     v2_mb_type[cbp&3][0]);
            if((cbp&3) != 3) coded_cbp= cbp ^ 0x3C;
            else             coded_cbp= cbp;

            put_bits(&s->pb, 
                     cbpy_tab[coded_cbp>>2][1], 
                     cbpy_tab[coded_cbp>>2][0]);
                        
            h263_pred_motion(s, 0, &pred_x, &pred_y);
            msmpeg4v2_encode_motion(s, motion_x - pred_x);
            msmpeg4v2_encode_motion(s, motion_y - pred_y);
        }else{
            put_bits(&s->pb, 
                     table_mb_non_intra[cbp + 64][1], 
                     table_mb_non_intra[cbp + 64][0]);

            /* motion vector */
            h263_pred_motion(s, 0, &pred_x, &pred_y);
            msmpeg4_encode_motion(s, motion_x - pred_x, 
                                  motion_y - pred_y);
        }
    } else {
	/* compute cbp */
	cbp = 0;
        coded_cbp = 0;
	for (i = 0; i < 6; i++) {
            int val, pred;
            val = (s->block_last_index[i] >= 1);
            cbp |= val << (5 - i);
            if (i < 4) {
                /* predict value for close blocks only for luma */
                pred = coded_block_pred(s, i, &coded_block);
                *coded_block = val;
                val = val ^ pred;
            }
            coded_cbp |= val << (5 - i);
	}
#if 0
        if (coded_cbp)
            printf("cbp=%x %x\n", cbp, coded_cbp);
#endif

        if(s->msmpeg4_version<=2){
            if (s->pict_type == I_TYPE) {
                put_bits(&s->pb, 
                         v2_intra_cbpc[cbp&3][1], v2_intra_cbpc[cbp&3][0]);
            } else {
                if (s->use_skip_mb_code)
                    put_bits(&s->pb, 1, 0);	/* mb coded */
                put_bits(&s->pb, 
                         v2_mb_type[(cbp&3) + 4][1], 
                         v2_mb_type[(cbp&3) + 4][0]);
            }
            put_bits(&s->pb, 1, 0);	/* no AC prediction yet */
            put_bits(&s->pb, 
                     cbpy_tab[cbp>>2][1], 
                     cbpy_tab[cbp>>2][0]);
        }else{
            if (s->pict_type == I_TYPE) {
                set_stat(ST_INTRA_MB);
                put_bits(&s->pb, 
                         table_mb_intra[coded_cbp][1], table_mb_intra[coded_cbp][0]);
            } else {
                if (s->use_skip_mb_code)
                    put_bits(&s->pb, 1, 0);	/* mb coded */
                put_bits(&s->pb, 
                         table_mb_non_intra[cbp][1], 
                         table_mb_non_intra[cbp][0]);
            }
            set_stat(ST_INTRA_MB);
            put_bits(&s->pb, 1, 0);	/* no AC prediction yet */
            if(s->inter_intra_pred){
                s->h263_aic_dir=0;
                put_bits(&s->pb, table_inter_intra[s->h263_aic_dir][1], table_inter_intra[s->h263_aic_dir][0]);
            }
        }
    }

    for (i = 0; i < 6; i++) {
        msmpeg4_encode_block(s, block[i], i);
    }
}

/* old ffmpeg msmpeg4v3 mode */
void ff_old_msmpeg4_dc_scale(MpegEncContext * s)
{
    if (s->qscale < 5){
        s->y_dc_scale = 8;
        s->c_dc_scale = 8;
    }else if (s->qscale < 9){
        s->y_dc_scale = 2 * s->qscale;
        s->c_dc_scale = (s->qscale + 13)>>1;
    }else{
        s->y_dc_scale = s->qscale + 8;
        s->c_dc_scale = (s->qscale + 13)>>1;
    }
}

static inline int msmpeg4v1_pred_dc(MpegEncContext * s, int n, 
                                    INT32 **dc_val_ptr)
{
    int i;

    if (n < 4) {
        i= 0;
    } else {
        i= n-3;
    }
    
    *dc_val_ptr= &s->last_dc[i];
    return s->last_dc[i]; 
}

static int get_dc(uint8_t *src, int stride, int scale)
{
    int y;
    int sum=0;
    for(y=0; y<8; y++){
        int x;
        for(x=0; x<8; x++){
            sum+=src[x + y*stride];
        }
    }
    return (sum + (scale>>1))/scale;
}

/* dir = 0: left, dir = 1: top prediction */
static inline int msmpeg4_pred_dc(MpegEncContext * s, int n, 
                             UINT16 **dc_val_ptr, int *dir_ptr)
{
    int a, b, c, wrap, pred, scale;
    INT16 *dc_val;

    /* find prediction */
    if (n < 4) {
	scale = s->y_dc_scale;
    } else {
	scale = s->c_dc_scale;
    }
    
    wrap = s->block_wrap[n];
    dc_val= s->dc_val[0] + s->block_index[n];

    /* B C
     * A X 
     */
    a = dc_val[ - 1];
    b = dc_val[ - 1 - wrap];
    c = dc_val[ - wrap];
    
    if(s->first_slice_line && (n&2)==0 && s->msmpeg4_version!=4){
        b=c=1024;
    }

    /* XXX: the following solution consumes divisions, but it does not
       necessitate to modify mpegvideo.c. The problem comes from the
       fact they decided to store the quantized DC (which would lead
       to problems if Q could vary !) */
#if defined ARCH_X86 && !defined PIC
    asm volatile(
        "movl %3, %%eax		\n\t"
	"shrl $1, %%eax		\n\t"
	"addl %%eax, %2		\n\t"
	"addl %%eax, %1		\n\t"
	"addl %0, %%eax		\n\t"
	"mull %4		\n\t"
	"movl %%edx, %0		\n\t"
	"movl %1, %%eax		\n\t"
	"mull %4		\n\t"
	"movl %%edx, %1		\n\t"
	"movl %2, %%eax		\n\t"
	"mull %4		\n\t"
	"movl %%edx, %2		\n\t"
	: "+b" (a), "+c" (b), "+D" (c)
	: "g" (scale), "S" (inverse[scale])
	: "%eax", "%edx"
    );
#else
    /* #elif defined (ARCH_ALPHA) */
    /* Divisions are extremely costly on Alpha; optimize the most
       common case. But they are costly everywhere...
     */
    if (scale == 8) {
	a = (a + (8 >> 1)) / 8;
	b = (b + (8 >> 1)) / 8;
	c = (c + (8 >> 1)) / 8;
    } else {
	a = (a + (scale >> 1)) / scale;
	b = (b + (scale >> 1)) / scale;
	c = (c + (scale >> 1)) / scale;
    }
#endif
    /* XXX: WARNING: they did not choose the same test as MPEG4. This
       is very important ! */
    if(s->msmpeg4_version>3){
        if(s->inter_intra_pred){
            uint8_t *dest;
            int wrap;
            
            if(n==1){
                pred=a;
                *dir_ptr = 0;
            }else if(n==2){
                pred=c;
                *dir_ptr = 1;
            }else if(n==3){
                if (abs(a - b) < abs(b - c)) {
                    pred = c;
                    *dir_ptr = 1;
                } else {
                    pred = a;
                    *dir_ptr = 0;
                }
            }else{
                if(n<4){
                    wrap= s->linesize;
                    dest= s->current_picture[0] + (((n>>1) + 2*s->mb_y) * 8*  wrap ) + ((n&1) + 2*s->mb_x) * 8;
                }else{
                    wrap= s->uvlinesize;
                    dest= s->current_picture[n-3] + (s->mb_y * 8 * wrap) + s->mb_x * 8;
                }
                if(s->mb_x==0) a= (1024 + (scale>>1))/scale;
                else           a= get_dc(dest-8, wrap, scale*8);
                if(s->mb_y==0) c= (1024 + (scale>>1))/scale;
                else           c= get_dc(dest-8*wrap, wrap, scale*8);
                
                if (s->h263_aic_dir==0) {
                    pred= a;
                    *dir_ptr = 0;
                }else if (s->h263_aic_dir==1) {
                    if(n==0){
                        pred= c;
                        *dir_ptr = 1;
                    }else{
                        pred= a;
                        *dir_ptr = 0;
                    }
                }else if (s->h263_aic_dir==2) {
                    if(n==0){
                        pred= a;
                        *dir_ptr = 0;
                    }else{
                        pred= c;
                        *dir_ptr = 1;
                    }
                } else {
                    pred= c;
                    *dir_ptr = 1;
                }
            }
        }else{
            if (abs(a - b) < abs(b - c)) {
                pred = c;
                *dir_ptr = 1;
            } else {
                pred = a;
                *dir_ptr = 0;
            }
        }
    }else{
        if (abs(a - b) <= abs(b - c)) {
            pred = c;
            *dir_ptr = 1;
        } else {
            pred = a;
            *dir_ptr = 0;
        }
    }

    /* update predictor */
    *dc_val_ptr = &dc_val[0];
    return pred;
}

#define DC_MAX 119

static void msmpeg4_encode_dc(MpegEncContext * s, int level, int n, int *dir_ptr)
{
    int sign, code;
    int pred;

    if(s->msmpeg4_version==1){
        INT32 *dc_val;
        pred = msmpeg4v1_pred_dc(s, n, &dc_val);
        
        /* update predictor */
        *dc_val= level;
    }else{
        UINT16 *dc_val;
        pred = msmpeg4_pred_dc(s, n, &dc_val, dir_ptr);

        /* update predictor */
        if (n < 4) {
            *dc_val = level * s->y_dc_scale;
        } else {
            *dc_val = level * s->c_dc_scale;
        }
    }

    /* do the prediction */
    level -= pred;

    if(s->msmpeg4_version<=2){
        if (n < 4) {
            put_bits(&s->pb, 
                     v2_dc_lum_table[level+256][1],
                     v2_dc_lum_table[level+256][0]);
        }else{
            put_bits(&s->pb, 
                     v2_dc_chroma_table[level+256][1],
                     v2_dc_chroma_table[level+256][0]);
        }
    }else{
        sign = 0;
        if (level < 0) {
            level = -level;
            sign = 1;
        }
        code = level;
        if (code > DC_MAX) 
            code = DC_MAX;

        if (s->dc_table_index == 0) {
            if (n < 4) {
                put_bits(&s->pb, table0_dc_lum[code][1], table0_dc_lum[code][0]);
            } else {
                put_bits(&s->pb, table0_dc_chroma[code][1], table0_dc_chroma[code][0]);
            }
        } else {
            if (n < 4) {
                put_bits(&s->pb, table1_dc_lum[code][1], table1_dc_lum[code][0]);
            } else {
                put_bits(&s->pb, table1_dc_chroma[code][1], table1_dc_chroma[code][0]);
            }
        }
            
        if (code == DC_MAX)
            put_bits(&s->pb, 8, level);
            
        if (level != 0) {
            put_bits(&s->pb, 1, sign);
        }
    }
}

/* Encoding of a block. Very similar to MPEG4 except for a different
   escape coding (same as H263) and more vlc tables.
 */
static inline void msmpeg4_encode_block(MpegEncContext * s, DCTELEM * block, int n)
{
    int level, run, last, i, j, last_index;
    int last_non_zero, sign, slevel;
    int code, run_diff, dc_pred_dir;
    const RLTable *rl;
    const UINT8 *scantable;

    if (s->mb_intra) {
        set_stat(ST_DC);
        msmpeg4_encode_dc(s, block[0], n, &dc_pred_dir);
        i = 1;
        if (n < 4) {
            rl = &rl_table[s->rl_table_index];
        } else {
            rl = &rl_table[3 + s->rl_chroma_table_index];
        }
        run_diff = 0;
        scantable= s->intra_scantable.permutated;
        set_stat(ST_INTRA_AC);
    } else {
        i = 0;
        rl = &rl_table[3 + s->rl_table_index];
        if(s->msmpeg4_version<=2)
            run_diff = 0;
        else
            run_diff = 1;
        scantable= s->inter_scantable.permutated;
        set_stat(ST_INTER_AC);
    }

    /* recalculate block_last_index for M$ wmv1 */
    if(s->msmpeg4_version==4 && s->block_last_index[n]>0){
        for(last_index=63; last_index>=0; last_index--){
            if(block[scantable[last_index]]) break;
        }
        s->block_last_index[n]= last_index;
    }else
        last_index = s->block_last_index[n];
    /* AC coefs */
    last_non_zero = i - 1;
    for (; i <= last_index; i++) {
	j = scantable[i];
	level = block[j];
	if (level) {
	    run = i - last_non_zero - 1;
	    last = (i == last_index);
	    sign = 0;
	    slevel = level;
	    if (level < 0) {
		sign = 1;
		level = -level;
	    }

            if(level<=MAX_LEVEL && run<=MAX_RUN){
                s->ac_stats[s->mb_intra][n>3][level][run][last]++;
            }
#if 0
else
    s->ac_stats[s->mb_intra][n>3][40][63][0]++; //esc3 like
#endif
            code = get_rl_index(rl, last, run, level);
            put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
            if (code == rl->n) {
                int level1, run1;

                level1 = level - rl->max_level[last][run];
                if (level1 < 1) 
                    goto esc2;
                code = get_rl_index(rl, last, run, level1);
                if (code == rl->n) {
                esc2:
                    put_bits(&s->pb, 1, 0);
                    if (level > MAX_LEVEL)
                        goto esc3;
                    run1 = run - rl->max_run[last][level] - run_diff;
                    if (run1 < 0)
                        goto esc3;
                    code = get_rl_index(rl, last, run1, level);
                    if (code == rl->n) {
                    esc3:
                        /* third escape */
                        put_bits(&s->pb, 1, 0);
                        put_bits(&s->pb, 1, last);
                        if(s->msmpeg4_version==4){
                            if(s->esc3_level_length==0){
                                s->esc3_level_length=8;
                                s->esc3_run_length= 6;
                                if(s->qscale<8)
                                    put_bits(&s->pb, 6, 3);
                                else
                                    put_bits(&s->pb, 8, 3);
                            }
                            put_bits(&s->pb, s->esc3_run_length, run);
                            put_bits(&s->pb, 1, sign);
                            put_bits(&s->pb, s->esc3_level_length, level);
                        }else{
                            put_bits(&s->pb, 6, run);
                            put_bits(&s->pb, 8, slevel & 0xff);
                        }
                    } else {
                        /* second escape */
                        put_bits(&s->pb, 1, 1);
                        put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
                        put_bits(&s->pb, 1, sign);