h264.c

播放H264文件的播放器

            return;
        }
    }else{
        const int16_t * C;
        int diagonal_ref;

        diagonal_ref= fetch_diagonal_mv(h, &C, scan8[4], list, 2);

        tprintf(h->s.avctx, "pred_8x16: (%2d %2d %2d) at %2d %2d %d list %d\n", diagonal_ref, C[0], C[1], h->s.mb_x, h->s.mb_y, n, list);

        if(diagonal_ref == ref){
            *mx= C[0];
            *my= C[1];
            return;
        }
    }

    //RARE
    pred_motion(h, n, 2, list, ref, mx, my);
}

static _inline void pred_pskip_motion(H264Context * const h, int * const mx, int * const my){
    const int top_ref = h->ref_cache[0][ scan8[0] - 8 ];
    const int left_ref= h->ref_cache[0][ scan8[0] - 1 ];

    tprintf(h->s.avctx, "pred_pskip: (%d) (%d) at %2d %2d\n", top_ref, left_ref, h->s.mb_x, h->s.mb_y);

    if(top_ref == PART_NOT_AVAILABLE || left_ref == PART_NOT_AVAILABLE
       || !( top_ref | *(uint32_t*)h->mv_cache[0][ scan8[0] - 8 ])
       || !(left_ref | *(uint32_t*)h->mv_cache[0][ scan8[0] - 1 ])){

        *mx = *my = 0;
        return;
    }

    pred_motion(h, 0, 4, 0, 0, mx, my);

    return;
}

static int get_scale_factor(H264Context * const h, int poc, int poc1, int i){
    int poc0 = h->ref_list[0][i].poc;
    int td = av_clip(poc1 - poc0, -128, 127);
    if(td == 0 || h->ref_list[0][i].long_ref){
        return 256;
    }else{
        int tb = av_clip(poc - poc0, -128, 127);
        int tx = (16384 + (FFABS(td) >> 1)) / td;
        return av_clip((tb*tx + 32) >> 6, -1024, 1023);
    }
}

static _inline void direct_dist_scale_factor(H264Context * const h){
    MpegEncContext * const s = &h->s;
    const int poc = h->s.current_picture_ptr->field_poc[ s->picture_structure == PICT_BOTTOM_FIELD ];
    const int poc1 = h->ref_list[1][0].poc;
    int i, field;
    for(field=0; field<2; field++){
        const int poc  = h->s.current_picture_ptr->field_poc[field];
        const int poc1 = h->ref_list[1][0].field_poc[field];
        for(i=0; i < 2*h->ref_count[0]; i++)
            h->dist_scale_factor_field[field][i^field] = get_scale_factor(h, poc, poc1, i+16);
    }

    for(i=0; i<h->ref_count[0]; i++){
        h->dist_scale_factor[i] = get_scale_factor(h, poc, poc1, i);
    }
}

static void fill_colmap(H264Context *h, int map[2][16+32], int list, int field, int colfield, int mbafi){
    MpegEncContext * const s = &h->s;
    Picture * const ref1 = &h->ref_list[1][0];
    int j, old_ref, rfield;
    int start= mbafi ? 16                      : 0;
    int end  = mbafi ? 16+2*h->ref_count[list] : h->ref_count[list];
    int interl= mbafi || s->picture_structure != PICT_FRAME;

    /* bogus; fills in for missing frames */
    memset(map[list], 0, sizeof(map[list]));

    for(rfield=0; rfield<2; rfield++){
        for(old_ref=0; old_ref<ref1->ref_count[colfield][list]; old_ref++){
            int poc = ref1->ref_poc[colfield][list][old_ref];

            if     (!interl)
                poc |= 3;
            else if( interl && (poc&3) == 3) //FIXME store all MBAFF references so this isnt needed
                poc= (poc&~3) + rfield + 1;

            for(j=start; j<end; j++){
                if(4*h->ref_list[list][j].frame_num + (h->ref_list[list][j].reference&3) == poc){
                    int cur_ref= mbafi ? (j-16)^field : j;
                    map[list][2*old_ref + (rfield^field) + 16] = cur_ref;
                    if(rfield == field)
                        map[list][old_ref] = cur_ref;
                    break;
                }
            }
        }
    }
}

static _inline void direct_ref_list_init(H264Context * const h){
    MpegEncContext * const s = &h->s;
    Picture * const ref1 = &h->ref_list[1][0];
    Picture * const cur = s->current_picture_ptr;
    int list, j, field;
    int sidx= (s->picture_structure&1)^1;
    int ref1sidx= (ref1->reference&1)^1;

    for(list=0; list<2; list++){
        cur->ref_count[sidx][list] = h->ref_count[list];
        for(j=0; j<h->ref_count[list]; j++)
            cur->ref_poc[sidx][list][j] = 4*h->ref_list[list][j].frame_num + (h->ref_list[list][j].reference&3);
    }

    if(s->picture_structure == PICT_FRAME){
        memcpy(cur->ref_count[1], cur->ref_count[0], sizeof(cur->ref_count[0]));
        memcpy(cur->ref_poc  [1], cur->ref_poc  [0], sizeof(cur->ref_poc  [0]));
    }

    cur->mbaff= FRAME_MBAFF;

    if(cur->pict_type != FF_B_TYPE || h->direct_spatial_mv_pred)
        return;

    for(list=0; list<2; list++){
        fill_colmap(h, h->map_col_to_list0, list, sidx, ref1sidx, 0);
        for(field=0; field<2; field++)
            fill_colmap(h, h->map_col_to_list0_field[field], list, field, field, 1);
    }
}

static _inline void pred_direct_motion(H264Context * const h, int *mb_type){
    MpegEncContext * const s = &h->s;
    int b8_stride = h->b8_stride;
    int b4_stride = h->b_stride;
    int mb_xy = h->mb_xy;
    int mb_type_col[2];
    const int16_t (*l1mv0)[2], (*l1mv1)[2];
    const int8_t *l1ref0, *l1ref1;
    const int is_b8x8 = IS_8X8(*mb_type);
    unsigned int sub_mb_type;
    int i8, i4;

#define MB_TYPE_16x16_OR_INTRA (MB_TYPE_16x16|MB_TYPE_INTRA4x4|MB_TYPE_INTRA16x16|MB_TYPE_INTRA_PCM)

    if(IS_INTERLACED(h->ref_list[1][0].mb_type[mb_xy])){ // AFL/AFR/FR/FL -> AFL/FL
        if(!IS_INTERLACED(*mb_type)){                    //     AFR/FR    -> AFL/FL
            int cur_poc = s->current_picture_ptr->poc;
            int *col_poc = h->ref_list[1]->field_poc;
            int col_parity = FFABS(col_poc[0] - cur_poc) >= FFABS(col_poc[1] - cur_poc);
            mb_xy= s->mb_x + ((s->mb_y&~1) + col_parity)*s->mb_stride;
            b8_stride = 0;
        }else if(!(s->picture_structure & h->ref_list[1][0].reference) && !h->ref_list[1][0].mbaff){// FL -> FL & differ parity
            int fieldoff= 2*(h->ref_list[1][0].reference)-3;
            mb_xy += s->mb_stride*fieldoff;
        }
        goto single_col;
    }else{                                               // AFL/AFR/FR/FL -> AFR/FR
        if(IS_INTERLACED(*mb_type)){                     // AFL       /FL -> AFR/FR
            mb_xy= s->mb_x + (s->mb_y&~1)*s->mb_stride;
            mb_type_col[0] = h->ref_list[1][0].mb_type[mb_xy];
            mb_type_col[1] = h->ref_list[1][0].mb_type[mb_xy + s->mb_stride];
            b8_stride *= 3;
            b4_stride *= 6;
            //FIXME IS_8X8(mb_type_col[0]) && !h->sps.direct_8x8_inference_flag
            if(    (mb_type_col[0] & MB_TYPE_16x16_OR_INTRA)
                && (mb_type_col[1] & MB_TYPE_16x16_OR_INTRA)
                && !is_b8x8){
                sub_mb_type = MB_TYPE_16x16|MB_TYPE_P0L0|MB_TYPE_P0L1|MB_TYPE_DIRECT2; /* B_SUB_8x8 */
                *mb_type   |= MB_TYPE_16x8 |MB_TYPE_L0L1|MB_TYPE_DIRECT2; /* B_16x8 */
            }else{
                sub_mb_type = MB_TYPE_16x16|MB_TYPE_P0L0|MB_TYPE_P0L1|MB_TYPE_DIRECT2; /* B_SUB_8x8 */
                *mb_type   |= MB_TYPE_8x8|MB_TYPE_L0L1;
            }
        }else{                                           //     AFR/FR    -> AFR/FR
single_col:
            mb_type_col[0] =
            mb_type_col[1] = h->ref_list[1][0].mb_type[mb_xy];
            if(IS_8X8(mb_type_col[0]) && !h->sps.direct_8x8_inference_flag){
                /* FIXME save sub mb types from previous frames (or derive from MVs)
                * so we know exactly what block size to use */
                sub_mb_type = MB_TYPE_8x8|MB_TYPE_P0L0|MB_TYPE_P0L1|MB_TYPE_DIRECT2; /* B_SUB_4x4 */
                *mb_type   |= MB_TYPE_8x8|MB_TYPE_L0L1;
            }else if(!is_b8x8 && (mb_type_col[0] & MB_TYPE_16x16_OR_INTRA)){
                sub_mb_type = MB_TYPE_16x16|MB_TYPE_P0L0|MB_TYPE_P0L1|MB_TYPE_DIRECT2; /* B_SUB_8x8 */
                *mb_type   |= MB_TYPE_16x16|MB_TYPE_P0L0|MB_TYPE_P0L1|MB_TYPE_DIRECT2; /* B_16x16 */
            }else{
                sub_mb_type = MB_TYPE_16x16|MB_TYPE_P0L0|MB_TYPE_P0L1|MB_TYPE_DIRECT2; /* B_SUB_8x8 */
                *mb_type   |= MB_TYPE_8x8|MB_TYPE_L0L1;
            }
        }
    }

    l1mv0  = &h->ref_list[1][0].motion_val[0][h->mb2b_xy [mb_xy]];
    l1mv1  = &h->ref_list[1][0].motion_val[1][h->mb2b_xy [mb_xy]];
    l1ref0 = &h->ref_list[1][0].ref_index [0][h->mb2b8_xy[mb_xy]];
    l1ref1 = &h->ref_list[1][0].ref_index [1][h->mb2b8_xy[mb_xy]];
    if(!b8_stride){
        if(s->mb_y&1){
            l1ref0 += h->b8_stride;
            l1ref1 += h->b8_stride;
            l1mv0  +=  2*b4_stride;
            l1mv1  +=  2*b4_stride;
        }
    }

    if(h->direct_spatial_mv_pred){
        int ref[2];
        int mv[2][2];
        int list;

        /* FIXME interlacing + spatial direct uses wrong colocated block positions */

        /* ref = min(neighbors) */
        for(list=0; list<2; list++){
            int refa = h->ref_cache[list][scan8[0] - 1];
            int refb = h->ref_cache[list][scan8[0] - 8];
            int refc = h->ref_cache[list][scan8[0] - 8 + 4];
            if(refc == PART_NOT_AVAILABLE)
                refc = h->ref_cache[list][scan8[0] - 8 - 1];
            ref[list] = FFMIN3((unsigned)refa, (unsigned)refb, (unsigned)refc);
            if(ref[list] < 0)
                ref[list] = -1;
        }

        if(ref[0] < 0 && ref[1] < 0){
            ref[0] = ref[1] = 0;
            mv[0][0] = mv[0][1] =
            mv[1][0] = mv[1][1] = 0;
        }else{
            for(list=0; list<2; list++){
                if(ref[list] >= 0)
                    pred_motion(h, 0, 4, list, ref[list], &mv[list][0], &mv[list][1]);
                else
                    mv[list][0] = mv[list][1] = 0;
            }
        }

        if(ref[1] < 0){
            if(!is_b8x8)
                *mb_type &= ~MB_TYPE_L1;
            sub_mb_type &= ~MB_TYPE_L1;
        }else if(ref[0] < 0){
            if(!is_b8x8)
                *mb_type &= ~MB_TYPE_L0;
            sub_mb_type &= ~MB_TYPE_L0;
        }

        if(IS_INTERLACED(*mb_type) != IS_INTERLACED(mb_type_col[0])){
            for(i8=0; i8<4; i8++){
                int x8 = i8&1;
                int y8 = i8>>1;
                int xy8 = x8+y8*b8_stride;
                int xy4 = 3*x8+y8*b4_stride;
                int a=0, b=0;

                if(is_b8x8 && !IS_DIRECT(h->sub_mb_type[i8]))
                    continue;
                h->sub_mb_type[i8] = sub_mb_type;

                fill_rectangle(&h->ref_cache[0][scan8[i8*4]], 2, 2, 8, (uint8_t)ref[0], 1);
                fill_rectangle(&h->ref_cache[1][scan8[i8*4]], 2, 2, 8, (uint8_t)ref[1], 1);
                if(!IS_INTRA(mb_type_col[y8])
                   && (   (l1ref0[xy8] == 0 && FFABS(l1mv0[xy4][0]) <= 1 && FFABS(l1mv0[xy4][1]) <= 1)
                       || (l1ref0[xy8]  < 0 && l1ref1[xy8] == 0 && FFABS(l1mv1[xy4][0]) <= 1 && FFABS(l1mv1[xy4][1]) <= 1))){
                    if(ref[0] > 0)
                        a= pack16to32(mv[0][0],mv[0][1]);
                    if(ref[1] > 0)
                        b= pack16to32(mv[1][0],mv[1][1]);
                }else{
                    a= pack16to32(mv[0][0],mv[0][1]);
                    b= pack16to32(mv[1][0],mv[1][1]);
                }
                fill_rectangle(&h->mv_cache[0][scan8[i8*4]], 2, 2, 8, a, 4);
                fill_rectangle(&h->mv_cache[1][scan8[i8*4]], 2, 2, 8, b, 4);
            }
        }else if(IS_16X16(*mb_type)){
            int a=0, b=0;

            fill_rectangle(&h->ref_cache[0][scan8[0]], 4, 4, 8, (uint8_t)ref[0], 1);
            fill_rectangle(&h->ref_cache[1][scan8[0]], 4, 4, 8, (uint8_t)ref[1], 1);
            if(!IS_INTRA(mb_type_col[0])
               && (   (l1ref0[0] == 0 && FFABS(l1mv0[0][0]) <= 1 && FFABS(l1mv0[0][1]) <= 1)
                   || (l1ref0[0]  < 0 && l1ref1[0] == 0 && FFABS(l1mv1[0][0]) <= 1 && FFABS(l1mv1[0][1]) <= 1
                       && (h->x264_build>33 || !h->x264_build)))){
                if(ref[0] > 0)
                    a= pack16to32(mv[0][0],mv[0][1]);
                if(ref[1] > 0)
                    b= pack16to32(mv[1][0],mv[1][1]);
            }else{
                a= pack16to32(mv[0][0],mv[0][1]);
                b= pack16to32(mv[1][0],mv[1][1]);
            }
            fill_rectangle(&h->mv_cache[0][scan8[0]], 4, 4, 8, a, 4);
            fill_rectangle(&h->mv_cache[1][scan8[0]], 4, 4, 8, b, 4);
        }else{
            for(i8=0; i8<4; i8++){
                const int x8 = i8&1;
                const int y8 = i8>>1;

                if(is_b8x8 && !IS_DIRECT(h->sub_mb_type[i8]))
                    continue;
                h->sub_mb_type[i8] = sub_mb_type;

                fill_rectangle(&h->mv_cache[0][scan8[i8*4]], 2, 2, 8, pack16to32(mv[0][0],mv[0][1]), 4);
                fill_rectangle(&h->mv_cache[1][scan8[i8*4]], 2, 2, 8, pack16to32(mv[1][0],mv[1][1]), 4);
                fill_rectangle(&h->ref_cache[0][scan8[i8*4]], 2, 2, 8, (uint8_t)ref[0], 1);
                fill_rectangle(&h->ref_cache[1][scan8[i8*4]], 2, 2, 8, (uint8_t)ref[1], 1);