/*

 * H.26L/H.264/AVC/JVT/14496-10/... direct mb/block decoding

 * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

/**

 * @file

 * H.264 / AVC / MPEG-4 part10 direct mb/block decoding.

 * @author Michael Niedermayer <michaelni@gmx.at>

 */

#include "avcodec.h"

#include "h264dec.h"

#include "h264_ps.h"

#include "mpegutils.h"

#include "rectangle.h"

#include "threadframe.h"

#include <assert.h>

static int get_scale_factor(const H264SliceContext *sl,

                            int poc, int poc1, int i)

{

    int poc0 = sl->ref_list[0][i].poc;

    int64_t pocdiff = poc1 - (int64_t)poc0;

    int td = av_clip_int8(pocdiff);

    if (pocdiff != (int)pocdiff)

        avpriv_request_sample(sl->h264->avctx, "pocdiff overflow");

    if (td == 0 || sl->ref_list[0][i].parent->long_ref) {

        return 256;

    } else {

        int64_t pocdiff0 = poc - (int64_t)poc0;

        int tb = av_clip_int8(pocdiff0);

        int tx = (16384 + (FFABS(td) >> 1)) / td;

        if (pocdiff0 != (int)pocdiff0)

            av_log(sl->h264->avctx, AV_LOG_DEBUG, "pocdiff0 overflow\n");

        return av_clip_intp2((tb * tx + 32) >> 6, 10);

    }

}

void ff_h264_direct_dist_scale_factor(const H264Context *const h,

                                      H264SliceContext *sl)

{

    const int poc  = FIELD_PICTURE(h) ? h->cur_pic_ptr->field_poc[h->picture_structure == PICT_BOTTOM_FIELD]

                                      : h->cur_pic_ptr->poc;

    const int poc1 = sl->ref_list[1][0].poc;

    int i, field;

    if (FRAME_MBAFF(h))

        for (field = 0; field < 2; field++) {

            const int poc  = h->cur_pic_ptr->field_poc[field];

            const int poc1 = sl->ref_list[1][0].parent->field_poc[field];

            for (i = 0; i < 2 * sl->ref_count[0]; i++)

                sl->dist_scale_factor_field[field][i ^ field] =

                    get_scale_factor(sl, poc, poc1, i + 16);

        }

    for (i = 0; i < sl->ref_count[0]; i++)

        sl->dist_scale_factor[i] = get_scale_factor(sl, poc, poc1, i);

}

static void fill_colmap(const H264Context *h, H264SliceContext *sl,

                        int map[2][16 + 32], int list,

                        int field, int colfield, int mbafi)

{

    const H264Picture *const ref1 = sl->ref_list[1][0].parent;

    int j, old_ref, rfield;

    int start  = mbafi ? 16                       : 0;

    int end    = mbafi ? 16 + 2 * sl->ref_count[0] : sl->ref_count[0];

    int interl = mbafi || h->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;

            // FIXME: store all MBAFF references so this is not needed

            else if (interl && (poc & 3) == 3)

                poc = (poc & ~3) + rfield + 1;

            for (j = start; j < end; j++) {

                if (4 * sl->ref_list[0][j].parent->frame_num +

                    (sl->ref_list[0][j].reference & 3) == poc) {

                    int cur_ref = mbafi ? (j - 16) ^ field : j;

                    if (ref1->mbaff)

                        map[list][2 * old_ref + (rfield ^ field) + 16] = cur_ref;

                    if (rfield == field || !interl)

                        map[list][old_ref] = cur_ref;

                    break;

                }

            }

        }

    }

}

void ff_h264_direct_ref_list_init(const H264Context *const h, H264SliceContext *sl)

{

    H264Ref *const ref1 = &sl->ref_list[1][0];

    H264Picture *const cur = h->cur_pic_ptr;

    int list, field;

    int sidx     = (h->picture_structure & 1) ^ 1;

    int ref1sidx = (ref1->reference      & 1) ^ 1;

    /* Updates to cur_pic are not safe once ff_thread_finish_setup() has been

     * called (other threads may already be reading these fields). */

    if (!h->setup_finished) {

        for (list = 0; list < sl->list_count; list++) {

            cur->ref_count[sidx][list] = sl->ref_count[list];

            for (int j = 0; j < sl->ref_count[list]; j++)

                cur->ref_poc[sidx][list][j] = 4 * sl->ref_list[list][j].parent->frame_num +

                                                 (sl->ref_list[list][j].reference & 3);

        }

        if (h->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]));

        }

        if (h->current_slice == 0) {

            cur->mbaff = FRAME_MBAFF(h);

        } else {

            av_assert0(cur->mbaff == FRAME_MBAFF(h));

        }

    }

    sl->col_fieldoff = 0;

    if (sl->list_count != 2 || !sl->ref_count[1])

        return;

    if (h->picture_structure == PICT_FRAME) {

        int cur_poc  = h->cur_pic_ptr->poc;

        const int *col_poc = sl->ref_list[1][0].parent->field_poc;

        if (col_poc[0] == INT_MAX && col_poc[1] == INT_MAX) {

            av_log(h->avctx, AV_LOG_ERROR, "co located POCs unavailable\n");

            sl->col_parity = 1;

        } else

            sl->col_parity = (FFABS(col_poc[0] - (int64_t)cur_poc) >=

                              FFABS(col_poc[1] - (int64_t)cur_poc));

        ref1sidx =

        sidx     = sl->col_parity;

    // FL -> FL & differ parity

    } else if (!(h->picture_structure & sl->ref_list[1][0].reference) &&

               !sl->ref_list[1][0].parent->mbaff) {

        sl->col_fieldoff = 2 * sl->ref_list[1][0].reference - 3;

    }

    if (sl->slice_type_nos != AV_PICTURE_TYPE_B || sl->direct_spatial_mv_pred)

        return;

    for (list = 0; list < 2; list++) {

        fill_colmap(h, sl, sl->map_col_to_list0, list, sidx, ref1sidx, 0);

        if (FRAME_MBAFF(h))

            for (field = 0; field < 2; field++)

                fill_colmap(h, sl, sl->map_col_to_list0_field[field], list, field,

                            field, 1);

    }

}

static void await_reference_mb_row(const H264Context *const h, H264Ref *ref,

                                   int mb_y)

{

    if (!HAVE_THREADS || !(h->avctx->active_thread_type & FF_THREAD_FRAME))

        return;

    int ref_field         = ref->reference - 1;

    int ref_field_picture = ref->parent->field_picture;

    int ref_height        = 16 * h->mb_height >> ref_field_picture;

    int row               = FFMIN(16 * mb_y >> ref_field_picture, ref_height - 1);

    /* FIXME: It can be safe to access mb stuff

     * even if pixels aren't deblocked yet. */

    ff_thread_await_progress(&ref->parent->tf, row,

                             ref_field_picture && ref_field);

    /* A frame references a field pair as a whole, so the wait above covers

     * its bottom field only, while the colocated data is read from the field

     * selected by col_parity. The two are decoded by different threads. */

    if (ref_field_picture && !FIELD_PICTURE(h))

        ff_thread_await_progress(&ref->parent->tf, row, 0);

}

static void pred_spatial_direct_motion(const H264Context *const h, H264SliceContext *sl,

                                       int *mb_type)

{

    int b8_stride = 2;

    int b4_stride = h->b_stride;

    int mb_xy = sl->mb_xy, mb_y = sl->mb_y;

    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 = MB_TYPE_L0L1;

    int i8, i4;

    int ref[2];

    int mv[2];

    int list;

    assert(sl->ref_list[1][0].reference & 3);

    await_reference_mb_row(h, &sl->ref_list[1][0],

                           sl->mb_y + !!IS_INTERLACED(*mb_type));

#define MB_TYPE_16x16_OR_INTRA (MB_TYPE_16x16 | MB_TYPE_INTRA4x4 | \

                                MB_TYPE_INTRA16x16 | MB_TYPE_INTRA_PCM)

    /* ref = min(neighbors) */

    for (list = 0; list < 2; list++) {

        int left_ref     = sl->ref_cache[list][scan8[0] - 1];

        int top_ref      = sl->ref_cache[list][scan8[0] - 8];

        int refc         = sl->ref_cache[list][scan8[0] - 8 + 4];

        const int16_t *C = sl->mv_cache[list][scan8[0]  - 8 + 4];

        if (refc == PART_NOT_AVAILABLE) {

            refc = sl->ref_cache[list][scan8[0] - 8 - 1];

            C    = sl->mv_cache[list][scan8[0]  - 8 - 1];

        }

        ref[list] = FFMIN3((unsigned)left_ref,

                           (unsigned)top_ref,

                           (unsigned)refc);

        if (ref[list] >= 0) {

            /* This is just pred_motion() but with the cases removed that

             * cannot happen for direct blocks. */

            const int16_t *const A = sl->mv_cache[list][scan8[0] - 1];

            const int16_t *const B = sl->mv_cache[list][scan8[0] - 8];

            int match_count = (left_ref == ref[list]) +

                              (top_ref  == ref[list]) +

                              (refc     == ref[list]);

            if (match_count > 1) { // most common

                mv[list] = pack16to32(mid_pred(A[0], B[0], C[0]),

                                      mid_pred(A[1], B[1], C[1]));

            } else {

                assert(match_count == 1);

                if (left_ref == ref[list])

                    mv[list] = AV_RN32A(A);

                else if (top_ref == ref[list])

                    mv[list] = AV_RN32A(B);

                else

                    mv[list] = AV_RN32A(C);

            }

            av_assert2(ref[list] < (sl->ref_count[list] << !!FRAME_MBAFF(h)));

        } else {

            int mask = ~(MB_TYPE_L0 << (2 * list));

            mv[list]  = 0;

            ref[list] = -1;

            if (!is_b8x8)

                *mb_type &= mask;

            sub_mb_type &= mask;

        }

    }

    if (ref[0] < 0 && ref[1] < 0) {

        ref[0] = ref[1] = 0;

        if (!is_b8x8)

            *mb_type |= MB_TYPE_L0L1;

        sub_mb_type |= MB_TYPE_L0L1;

    }

    if (!(is_b8x8 | mv[0] | mv[1])) {

        fill_rectangle(&sl->ref_cache[0][scan8[0]], 4, 4, 8, (uint8_t)ref[0], 1);

        fill_rectangle(&sl->ref_cache[1][scan8[0]], 4, 4, 8, (uint8_t)ref[1], 1);

        fill_rectangle(&sl->mv_cache[0][scan8[0]], 4, 4, 8, 0, 4);

        fill_rectangle(&sl->mv_cache[1][scan8[0]], 4, 4, 8, 0, 4);

        *mb_type = (*mb_type & ~(MB_TYPE_8x8 | MB_TYPE_16x8 | MB_TYPE_8x16 |

                                 MB_TYPE_P1L0 | MB_TYPE_P1L1)) |

                   MB_TYPE_16x16 | MB_TYPE_DIRECT2;

        return;

    }

    if (sl->ref_list[1][0].parent->field_picture ||

        IS_INTERLACED(sl->ref_list[1][0].parent->mb_type[mb_xy])) { // AFL/AFR/FR/FL -> AFL/FL

        if (!IS_INTERLACED(*mb_type)) {                    //     AFR/FR    -> AFL/FL

            mb_y  = (sl->mb_y & ~1) + sl->col_parity;

            mb_xy = sl->mb_x +

                    ((sl->mb_y & ~1) + sl->col_parity) * h->mb_stride;

            b8_stride = 0;

        } else {

            mb_y  += sl->col_fieldoff;

            mb_xy += h->mb_stride * sl->col_fieldoff; // non-zero for FL -> FL & differ parity

        }

        goto single_col;

    } else {                                             // AFL/AFR/FR/FL -> AFR/FR

        if (IS_INTERLACED(*mb_type)) {                   // AFL       /FL -> AFR/FR

            mb_y           =  sl->mb_y & ~1;

            mb_xy          = (sl->mb_y & ~1) * h->mb_stride + sl->mb_x;

            mb_type_col[0] = sl->ref_list[1][0].parent->mb_type[mb_xy];

            mb_type_col[1] = sl->ref_list[1][0].parent->mb_type[mb_xy + h->mb_stride];

            b8_stride      = 2 + 4 * h->mb_stride;

            b4_stride     *= 6;

            if (IS_INTERLACED(mb_type_col[0]) !=

                IS_INTERLACED(mb_type_col[1])) {

                mb_type_col[0] &= ~MB_TYPE_INTERLACED;

                mb_type_col[1] &= ~MB_TYPE_INTERLACED;

            }

            sub_mb_type |= MB_TYPE_16x16 | MB_TYPE_DIRECT2; /* B_SUB_8x8 */

            if ((mb_type_col[0] & MB_TYPE_16x16_OR_INTRA) &&

                (mb_type_col[1] & MB_TYPE_16x16_OR_INTRA) &&

                !is_b8x8) {

                *mb_type |= MB_TYPE_16x8 | MB_TYPE_DIRECT2;  /* B_16x8 */

            } else {

                *mb_type |= MB_TYPE_8x8;

            }

        } else {                                         //     AFR/FR    -> AFR/FR

single_col:

            mb_type_col[0] =

            mb_type_col[1] = sl->ref_list[1][0].parent->mb_type[mb_xy];

            sub_mb_type |= MB_TYPE_16x16 | MB_TYPE_DIRECT2; /* B_SUB_8x8 */

            if (!is_b8x8 && (mb_type_col[0] & MB_TYPE_16x16_OR_INTRA)) {

                *mb_type |= MB_TYPE_16x16 | MB_TYPE_DIRECT2; /* B_16x16 */

            } else if (!is_b8x8 &&

                       (mb_type_col[0] & (MB_TYPE_16x8 | MB_TYPE_8x16))) {

                *mb_type |= MB_TYPE_DIRECT2 |

                            (mb_type_col[0] & (MB_TYPE_16x8 | MB_TYPE_8x16));

            } else {

                if (!h->ps.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_16x16); /* B_SUB_4x4 */

                }

                *mb_type |= MB_TYPE_8x8;

            }

        }

    }

    await_reference_mb_row(h, &sl->ref_list[1][0], mb_y);

    l1mv0  = (void*)&sl->ref_list[1][0].parent->motion_val[0][h->mb2b_xy[mb_xy]];

    l1mv1  = (void*)&sl->ref_list[1][0].parent->motion_val[1][h->mb2b_xy[mb_xy]];

    l1ref0 = &sl->ref_list[1][0].parent->ref_index[0][4 * mb_xy];

    l1ref1 = &sl->ref_list[1][0].parent->ref_index[1][4 * mb_xy];

    if (!b8_stride) {

        if (sl->mb_y & 1) {

            l1ref0 += 2;

            l1ref1 += 2;

            l1mv0  += 2 * b4_stride;

            l1mv1  += 2 * b4_stride;

        }

    }

    if (IS_INTERLACED(*mb_type) != IS_INTERLACED(mb_type_col[0])) {

        int n = 0;

        for (i8 = 0; i8 < 4; i8++) {

            int x8  = i8 & 1;

            int y8  = i8 >> 1;

            int xy8 = x8     + y8 * b8_stride;

            int xy4 = x8 * 3 + y8 * b4_stride;

            int a, b;

            if (is_b8x8 && !IS_DIRECT(sl->sub_mb_type[i8]))

                continue;

            sl->sub_mb_type[i8] = sub_mb_type;

            fill_rectangle(&sl->ref_cache[0][scan8[i8 * 4]], 2, 2, 8,

                           (uint8_t)ref[0], 1);

            fill_rectangle(&sl->ref_cache[1][scan8[i8 * 4]], 2, 2, 8,

                           (uint8_t)ref[1], 1);

            if (!IS_INTRA(mb_type_col[y8]) && !sl->ref_list[1][0].parent->long_ref &&

                ((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))) {

                a =

                b = 0;

                if (ref[0] > 0)

                    a = mv[0];

                if (ref[1] > 0)

                    b = mv[1];

                n++;

            } else {

                a = mv[0];

                b = mv[1];

            }

            fill_rectangle(&sl->mv_cache[0][scan8[i8 * 4]], 2, 2, 8, a, 4);

            fill_rectangle(&sl->mv_cache[1][scan8[i8 * 4]], 2, 2, 8, b, 4);

        }

        if (!is_b8x8 && !(n & 3))

            *mb_type = (*mb_type & ~(MB_TYPE_8x8 | MB_TYPE_16x8 | MB_TYPE_8x16 |

                                     MB_TYPE_P1L0 | MB_TYPE_P1L1)) |

                       MB_TYPE_16x16 | MB_TYPE_DIRECT2;

    } else if (IS_16X16(*mb_type)) {

        int a, b;

        fill_rectangle(&sl->ref_cache[0][scan8[0]], 4, 4, 8, (uint8_t)ref[0], 1);

        fill_rectangle(&sl->ref_cache[1][scan8[0]], 4, 4, 8, (uint8_t)ref[1], 1);

        if (!IS_INTRA(mb_type_col[0]) && !sl->ref_list[1][0].parent->long_ref &&

            ((l1ref0[0] == 0 &&

              FFABS(l1mv0[0][0]) <= 1 &&

              FFABS(l1mv0[0][1]) <= 1) ||

             (l1ref0[0] < 0 && !l1ref1[0] &&

              FFABS(l1mv1[0][0]) <= 1 &&

              FFABS(l1mv1[0][1]) <= 1 &&

              h->x264_build > 33U))) {

            a = b = 0;

            if (ref[0] > 0)

                a = mv[0];

            if (ref[1] > 0)

                b = mv[1];

        } else {

            a = mv[0];

            b = mv[1];

        }

        fill_rectangle(&sl->mv_cache[0][scan8[0]], 4, 4, 8, a, 4);

        fill_rectangle(&sl->mv_cache[1][scan8[0]], 4, 4, 8, b, 4);

    } else {

        int n = 0;

        for (i8 = 0; i8 < 4; i8++) {

            const int x8 = i8 & 1;

            const int y8 = i8 >> 1;

            if (is_b8x8 && !IS_DIRECT(sl->sub_mb_type[i8]))

                continue;

            sl->sub_mb_type[i8] = sub_mb_type;

            fill_rectangle(&sl->mv_cache[0][scan8[i8 * 4]], 2, 2, 8, mv[0], 4);

            fill_rectangle(&sl->mv_cache[1][scan8[i8 * 4]], 2, 2, 8, mv[1], 4);

            fill_rectangle(&sl->ref_cache[0][scan8[i8 * 4]], 2, 2, 8,

                           (uint8_t)ref[0], 1);

            fill_rectangle(&sl->ref_cache[1][scan8[i8 * 4]], 2, 2, 8,

                           (uint8_t)ref[1], 1);

            assert(b8_stride == 2);

            /* col_zero_flag */

            if (!IS_INTRA(mb_type_col[0]) && !sl->ref_list[1][0].parent->long_ref &&

                (l1ref0[i8] == 0 ||

                 (l1ref0[i8] < 0 &&

                  l1ref1[i8] == 0 &&

                  h->x264_build > 33U))) {

                const int16_t (*l1mv)[2] = l1ref0[i8] == 0 ? l1mv0 : l1mv1;

                if (IS_SUB_8X8(sub_mb_type)) {

                    const int16_t *mv_col = l1mv[x8 * 3 + y8 * 3 * b4_stride];

                    if (FFABS(mv_col[0]) <= 1 && FFABS(mv_col[1]) <= 1) {

                        if (ref[0] == 0)

                            fill_rectangle(&sl->mv_cache[0][scan8[i8 * 4]], 2, 2,

                                           8, 0, 4);

                        if (ref[1] == 0)

                            fill_rectangle(&sl->mv_cache[1][scan8[i8 * 4]], 2, 2,

                                           8, 0, 4);

                        n += 4;

                    }

                } else {

                    int m = 0;

                    for (i4 = 0; i4 < 4; i4++) {

                        const int16_t *mv_col = l1mv[x8 * 2 + (i4 & 1) +

                                                     (y8 * 2 + (i4 >> 1)) * b4_stride];

                        if (FFABS(mv_col[0]) <= 1 && FFABS(mv_col[1]) <= 1) {

                            if (ref[0] == 0)

                                AV_ZERO32(sl->mv_cache[0][scan8[i8 * 4 + i4]]);

                            if (ref[1] == 0)

                                AV_ZERO32(sl->mv_cache[1][scan8[i8 * 4 + i4]]);

                            m++;

                        }

                    }

                    if (!(m & 3))

                        sl->sub_mb_type[i8] += MB_TYPE_16x16 - MB_TYPE_8x8;

                    n += m;

                }

            }

        }

        if (!is_b8x8 && !(n & 15))

            *mb_type = (*mb_type & ~(MB_TYPE_8x8 | MB_TYPE_16x8 | MB_TYPE_8x16 |

                                     MB_TYPE_P1L0 | MB_TYPE_P1L1)) |

                       MB_TYPE_16x16 | MB_TYPE_DIRECT2;

    }

}

static void pred_temp_direct_motion(const H264Context *const h, H264SliceContext *sl,

                                    int *mb_type)

{

    int b8_stride = 2;

    int b4_stride = h->b_stride;

    int mb_xy = sl->mb_xy, mb_y = sl->mb_y;

    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;

    assert(sl->ref_list[1][0].reference & 3);

    await_reference_mb_row(h, &sl->ref_list[1][0],

                           sl->mb_y + !!IS_INTERLACED(*mb_type));

    if (sl->ref_list[1][0].parent->field_picture ||

        IS_INTERLACED(sl->ref_list[1][0].parent->mb_type[mb_xy])) { // AFL/AFR/FR/FL -> AFL/FL

        if (!IS_INTERLACED(*mb_type)) {                    //     AFR/FR    -> AFL/FL

            mb_y  = (sl->mb_y & ~1) + sl->col_parity;

            mb_xy = sl->mb_x +

                    ((sl->mb_y & ~1) + sl->col_parity) * h->mb_stride;

            b8_stride = 0;

        } else {

            mb_y  += sl->col_fieldoff;

            mb_xy += h->mb_stride * sl->col_fieldoff; // non-zero for FL -> FL & differ parity

        }

        goto single_col;

    } else {                                        // AFL/AFR/FR/FL -> AFR/FR

        if (IS_INTERLACED(*mb_type)) {              // AFL       /FL -> AFR/FR

            mb_y           = sl->mb_y & ~1;

            mb_xy          = sl->mb_x + (sl->mb_y & ~1) * h->mb_stride;

            mb_type_col[0] = sl->ref_list[1][0].parent->mb_type[mb_xy];

            mb_type_col[1] = sl->ref_list[1][0].parent->mb_type[mb_xy + h->mb_stride];

            b8_stride      = 2 + 4 * h->mb_stride;

            b4_stride     *= 6;

            if (IS_INTERLACED(mb_type_col[0]) !=

                IS_INTERLACED(mb_type_col[1])) {

                mb_type_col[0] &= ~MB_TYPE_INTERLACED;

                mb_type_col[1] &= ~MB_TYPE_INTERLACED;

            }

            sub_mb_type = MB_TYPE_16x16 | MB_TYPE_P0L0 | MB_TYPE_P0L1 |

                          MB_TYPE_DIRECT2;                  /* B_SUB_8x8 */

            if ((mb_type_col[0] & MB_TYPE_16x16_OR_INTRA) &&

                (mb_type_col[1] & MB_TYPE_16x16_OR_INTRA) &&

                !is_b8x8) {

                *mb_type |= MB_TYPE_16x8 | MB_TYPE_L0L1 |

                            MB_TYPE_DIRECT2;                /* B_16x8 */

            } else {

                *mb_type |= MB_TYPE_8x8 | MB_TYPE_L0L1;

            }

        } else {                                    //     AFR/FR    -> AFR/FR

single_col:

            mb_type_col[0]     =

                mb_type_col[1] = sl->ref_list[1][0].parent->mb_type[mb_xy];

            sub_mb_type = MB_TYPE_16x16 | MB_TYPE_P0L0 | MB_TYPE_P0L1 |

                          MB_TYPE_DIRECT2;                  /* B_SUB_8x8 */

            if (!is_b8x8 && (mb_type_col[0] & MB_TYPE_16x16_OR_INTRA)) {

                *mb_type |= MB_TYPE_16x16 | MB_TYPE_P0L0 | MB_TYPE_P0L1 |

                            MB_TYPE_DIRECT2;                /* B_16x16 */

            } else if (!is_b8x8 &&

                       (mb_type_col[0] & (MB_TYPE_16x8 | MB_TYPE_8x16))) {

                *mb_type |= MB_TYPE_L0L1 | MB_TYPE_DIRECT2 |

                            (mb_type_col[0] & (MB_TYPE_16x8 | MB_TYPE_8x16));

            } else {

                if (!h->ps.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;

            }

        }

    }

    await_reference_mb_row(h, &sl->ref_list[1][0], mb_y);

    l1mv0  = (void*)&sl->ref_list[1][0].parent->motion_val[0][h->mb2b_xy[mb_xy]];

    l1mv1  = (void*)&sl->ref_list[1][0].parent->motion_val[1][h->mb2b_xy[mb_xy]];

    l1ref0 = &sl->ref_list[1][0].parent->ref_index[0][4 * mb_xy];

    l1ref1 = &sl->ref_list[1][0].parent->ref_index[1][4 * mb_xy];

    if (!b8_stride) {

        if (sl->mb_y & 1) {

            l1ref0 += 2;

            l1ref1 += 2;

            l1mv0  += 2 * b4_stride;

            l1mv1  += 2 * b4_stride;

        }

    }

    {

        const int *map_col_to_list0[2] = { sl->map_col_to_list0[0],

                                           sl->map_col_to_list0[1] };

        const int *dist_scale_factor = sl->dist_scale_factor;

        int ref_offset;

        if (FRAME_MBAFF(h) && IS_INTERLACED(*mb_type)) {

            map_col_to_list0[0] = sl->map_col_to_list0_field[sl->mb_y & 1][0];

            map_col_to_list0[1] = sl->map_col_to_list0_field[sl->mb_y & 1][1];

            dist_scale_factor   = sl->dist_scale_factor_field[sl->mb_y & 1];

        }

        ref_offset = (sl->ref_list[1][0].parent->mbaff << 4) & (mb_type_col[0] >> 3);

        if (IS_INTERLACED(*mb_type) != IS_INTERLACED(mb_type_col[0])) {

            int y_shift = 2 * !IS_INTERLACED(*mb_type);

            assert(h->ps.sps->direct_8x8_inference_flag);

            for (i8 = 0; i8 < 4; i8++) {

                const int x8 = i8 & 1;

                const int y8 = i8 >> 1;

                int ref0, scale;

                const int16_t (*l1mv)[2] = l1mv0;

                if (is_b8x8 && !IS_DIRECT(sl->sub_mb_type[i8]))

                    continue;

                sl->sub_mb_type[i8] = sub_mb_type;

                fill_rectangle(&sl->ref_cache[1][scan8[i8 * 4]], 2, 2, 8, 0, 1);

                if (IS_INTRA(mb_type_col[y8])) {

                    fill_rectangle(&sl->ref_cache[0][scan8[i8 * 4]], 2, 2, 8, 0, 1);

                    fill_rectangle(&sl->mv_cache[0][scan8[i8 * 4]], 2, 2, 8, 0, 4);

                    fill_rectangle(&sl->mv_cache[1][scan8[i8 * 4]], 2, 2, 8, 0, 4);

                    continue;

                }

                ref0 = l1ref0[x8 + y8 * b8_stride];

                if (ref0 >= 0)

                    ref0 = map_col_to_list0[0][ref0 + ref_offset];

                else {

                    ref0 = map_col_to_list0[1][l1ref1[x8 + y8 * b8_stride] +

                                               ref_offset];

                    l1mv = l1mv1;

                }

                scale = dist_scale_factor[ref0];

                fill_rectangle(&sl->ref_cache[0][scan8[i8 * 4]], 2, 2, 8,

                               ref0, 1);

                {

                    const int16_t *mv_col = l1mv[x8 * 3 + y8 * b4_stride];

                    int my_col            = (mv_col[1] * (1 << y_shift)) / 2;

                    int mx                = (scale * mv_col[0] + 128) >> 8;

                    int my                = (scale * my_col    + 128) >> 8;

                    fill_rectangle(&sl->mv_cache[0][scan8[i8 * 4]], 2, 2, 8,

                                   pack16to32(mx, my), 4);

                    fill_rectangle(&sl->mv_cache[1][scan8[i8 * 4]], 2, 2, 8,

                                   pack16to32(mx - mv_col[0], my - my_col), 4);

                }

            }

            return;

        }

        /* one-to-one mv scaling */

        if (IS_16X16(*mb_type)) {

            int ref, mv0, mv1;

            fill_rectangle(&sl->ref_cache[1][scan8[0]], 4, 4, 8, 0, 1);

            if (IS_INTRA(mb_type_col[0])) {

                ref = mv0 = mv1 = 0;

            } else {

                const int ref0 = l1ref0[0] >= 0 ? map_col_to_list0[0][l1ref0[0] + ref_offset]

                                                : map_col_to_list0[1][l1ref1[0] + ref_offset];

                const int scale = dist_scale_factor[ref0];

                const int16_t *mv_col = l1ref0[0] >= 0 ? l1mv0[0] : l1mv1[0];

                int mv_l0[2];

                mv_l0[0] = (scale * mv_col[0] + 128) >> 8;

                mv_l0[1] = (scale * mv_col[1] + 128) >> 8;

                ref      = ref0;

                mv0      = pack16to32(mv_l0[0], mv_l0[1]);

                mv1      = pack16to32(mv_l0[0] - mv_col[0], mv_l0[1] - mv_col[1]);

            }

            fill_rectangle(&sl->ref_cache[0][scan8[0]], 4, 4, 8, ref, 1);

            fill_rectangle(&sl->mv_cache[0][scan8[0]], 4, 4, 8, mv0, 4);

            fill_rectangle(&sl->mv_cache[1][scan8[0]], 4, 4, 8, mv1, 4);

        } else {

            for (i8 = 0; i8 < 4; i8++) {

                const int x8 = i8 & 1;

                const int y8 = i8 >> 1;

                int ref0, scale;

                const int16_t (*l1mv)[2] = l1mv0;

                if (is_b8x8 && !IS_DIRECT(sl->sub_mb_type[i8]))

                    continue;

                sl->sub_mb_type[i8] = sub_mb_type;

                fill_rectangle(&sl->ref_cache[1][scan8[i8 * 4]], 2, 2, 8, 0, 1);

                if (IS_INTRA(mb_type_col[0])) {

                    fill_rectangle(&sl->ref_cache[0][scan8[i8 * 4]], 2, 2, 8, 0, 1);

                    fill_rectangle(&sl->mv_cache[0][scan8[i8 * 4]], 2, 2, 8, 0, 4);

                    fill_rectangle(&sl->mv_cache[1][scan8[i8 * 4]], 2, 2, 8, 0, 4);

                    continue;

                }

                assert(b8_stride == 2);

                ref0 = l1ref0[i8];

                if (ref0 >= 0)

                    ref0 = map_col_to_list0[0][ref0 + ref_offset];

                else {

                    ref0 = map_col_to_list0[1][l1ref1[i8] + ref_offset];

                    l1mv = l1mv1;

                }

                scale = dist_scale_factor[ref0];

                fill_rectangle(&sl->ref_cache[0][scan8[i8 * 4]], 2, 2, 8,

                               ref0, 1);

                if (IS_SUB_8X8(sub_mb_type)) {

                    const int16_t *mv_col = l1mv[x8 * 3 + y8 * 3 * b4_stride];

                    int mx                = (scale * mv_col[0] + 128) >> 8;

                    int my                = (scale * mv_col[1] + 128) >> 8;

                    fill_rectangle(&sl->mv_cache[0][scan8[i8 * 4]], 2, 2, 8,

                                   pack16to32(mx, my), 4);

                    fill_rectangle(&sl->mv_cache[1][scan8[i8 * 4]], 2, 2, 8,

                                   pack16to32(mx - mv_col[0], my - mv_col[1]), 4);

                } else {

                    for (i4 = 0; i4 < 4; i4++) {

                        const int16_t *mv_col = l1mv[x8 * 2 + (i4 & 1) +

                                                     (y8 * 2 + (i4 >> 1)) * b4_stride];

                        int16_t *mv_l0 = sl->mv_cache[0][scan8[i8 * 4 + i4]];

                        mv_l0[0] = (scale * mv_col[0] + 128) >> 8;

                        mv_l0[1] = (scale * mv_col[1] + 128) >> 8;

                        AV_WN32A(sl->mv_cache[1][scan8[i8 * 4 + i4]],

                                 pack16to32(mv_l0[0] - mv_col[0],

                                            mv_l0[1] - mv_col[1]));

                    }

                }

            }

        }

    }

}

void ff_h264_pred_direct_motion(const H264Context *const h, H264SliceContext *sl,

                                int *mb_type)

{

    if (sl->direct_spatial_mv_pred)

        pred_spatial_direct_motion(h, sl, mb_type);

    else

        pred_temp_direct_motion(h, sl, mb_type);

}