/*
  * H.26L/H.264/AVC/JVT/14496-10/... motion vector predicion
  * 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 / MPEG4 part10 motion vector predicion.
  * @author Michael Niedermayer <michaelni@gmx.at>
  */
 

 #ifndef AVCODEC_H264_MVPRED_H
 #define AVCODEC_H264_MVPRED_H
 

 #include "internal.h"
 #include "avcodec.h"
 #include "h264.h"

 #include "libavutil/avassert.h"

 static av_always_inline int fetch_diagonal_mv(H264Context *h, const int16_t **C,
                                               int i, int list, int part_width)
 {
     const int topright_ref = h->ref_cache[list][i - 8 + part_width];

 
     /* there is no consistent mapping of mvs to neighboring locations that will
      * make mbaff happy, so we can't move all this logic to fill_caches */

     if (FRAME_MBAFF(h)) {

 #define SET_DIAG_MV(MV_OP, REF_OP, XY, Y4)                              \
         const int xy = XY, y4 = Y4;                                     \

         const int mb_type = mb_types[xy + (y4 >> 2) * h->mb_stride];    \

         if (!USES_LIST(mb_type, list))                                  \
             return LIST_NOT_USED;                                       \

         mv = h->cur_pic_ptr->motion_val[list][h->mb2b_xy[xy] + 3 + y4 * h->b_stride]; \

         h->mv_cache[list][scan8[0] - 2][0] = mv[0];                     \
         h->mv_cache[list][scan8[0] - 2][1] = mv[1] MV_OP;               \

         return h->cur_pic_ptr->ref_index[list][4 * xy + 1 + (y4 & ~1)] REF_OP;

 
         if (topright_ref == PART_NOT_AVAILABLE
             && i >= scan8[0] + 8 && (i & 7) == 4
             && h->ref_cache[list][scan8[0] - 1] != PART_NOT_AVAILABLE) {

             const uint32_t *mb_types = h->cur_pic_ptr->mb_type;

             const int16_t *mv;

             AV_ZERO32(h->mv_cache[list][scan8[0] - 2]);
             *C = h->mv_cache[list][scan8[0] - 2];

             if (!MB_FIELD(h) && IS_INTERLACED(h->left_type[0])) {

                 SET_DIAG_MV(* 2, >> 1, h->left_mb_xy[0] + h->mb_stride,
                             (h->mb_y & 1) * 2 + (i >> 5));

             }

             if (MB_FIELD(h) && !IS_INTERLACED(h->left_type[0])) {

                 // left shift will turn LIST_NOT_USED into PART_NOT_AVAILABLE, but that's OK.

                 SET_DIAG_MV(/ 2, << 1, h->left_mb_xy[i >= 36], ((i >> 2)) & 3);

             }
         }
 #undef SET_DIAG_MV
     }
 

     if (topright_ref != PART_NOT_AVAILABLE) {
         *C = h->mv_cache[list][i - 8 + part_width];

         return topright_ref;

     } else {

         tprintf(h->avctx, "topright MV not available\n");

         *C = h->mv_cache[list][i - 8 - 1];
         return h->ref_cache[list][i - 8 - 1];

     }
 }
 
 /**

  * Get the predicted MV.

  * @param n the block index
  * @param part_width the width of the partition (4, 8,16) -> (1, 2, 4)
  * @param mx the x component of the predicted motion vector
  * @param my the y component of the predicted motion vector
  */

 static av_always_inline void pred_motion(H264Context *const h, int n,
                                          int part_width, int list, int ref,
                                          int *const mx, int *const my)
 {
     const int index8       = scan8[n];
     const int top_ref      = h->ref_cache[list][index8 - 8];
     const int left_ref     = h->ref_cache[list][index8 - 1];
     const int16_t *const A = h->mv_cache[list][index8 - 1];
     const int16_t *const B = h->mv_cache[list][index8 - 8];
     const int16_t *C;

     int diagonal_ref, match_count;
 

     av_assert2(part_width == 1 || part_width == 2 || part_width == 4);

 
 /* mv_cache

  * B . . A T T T T
  * U . . L . . , .
  * U . . L . . . .
  * U . . L . . , .
  * . . . L . . . .
  */
 
     diagonal_ref = fetch_diagonal_mv(h, &C, index8, list, part_width);
     match_count  = (diagonal_ref == ref) + (top_ref == ref) + (left_ref == ref);

     tprintf(h->avctx, "pred_motion match_count=%d\n", match_count);

     if (match_count > 1) { //most common
         *mx = mid_pred(A[0], B[0], C[0]);
         *my = mid_pred(A[1], B[1], C[1]);
     } else if (match_count == 1) {
         if (left_ref == ref) {
             *mx = A[0];
             *my = A[1];
         } else if (top_ref == ref) {
             *mx = B[0];
             *my = B[1];
         } else {
             *mx = C[0];
             *my = C[1];

         }

     } else {
         if (top_ref      == PART_NOT_AVAILABLE &&
             diagonal_ref == PART_NOT_AVAILABLE &&
             left_ref     != PART_NOT_AVAILABLE) {
             *mx = A[0];
             *my = A[1];
         } else {
             *mx = mid_pred(A[0], B[0], C[0]);
             *my = mid_pred(A[1], B[1], C[1]);

         }
     }
 

     tprintf(h->avctx,

             "pred_motion (%2d %2d %2d) (%2d %2d %2d) (%2d %2d %2d) -> (%2d %2d %2d) at %2d %2d %d list %d\n",
             top_ref, B[0], B[1], diagonal_ref, C[0], C[1], left_ref,

             A[0], A[1], ref, *mx, *my, h->mb_x, h->mb_y, n, list);

 }
 
 /**

  * Get the directionally predicted 16x8 MV.

  * @param n the block index
  * @param mx the x component of the predicted motion vector
  * @param my the y component of the predicted motion vector
  */

 static av_always_inline void pred_16x8_motion(H264Context *const h,
                                               int n, int list, int ref,
                                               int *const mx, int *const my)
 {
     if (n == 0) {
         const int top_ref      = h->ref_cache[list][scan8[0] - 8];
         const int16_t *const B = h->mv_cache[list][scan8[0] - 8];
 

         tprintf(h->avctx, "pred_16x8: (%2d %2d %2d) at %2d %2d %d list %d\n",
                 top_ref, B[0], B[1], h->mb_x, h->mb_y, n, list);

 
         if (top_ref == ref) {
             *mx = B[0];
             *my = B[1];

             return;
         }

     } else {
         const int left_ref     = h->ref_cache[list][scan8[8] - 1];
         const int16_t *const A = h->mv_cache[list][scan8[8] - 1];

         tprintf(h->avctx, "pred_16x8: (%2d %2d %2d) at %2d %2d %d list %d\n",
                 left_ref, A[0], A[1], h->mb_x, h->mb_y, n, list);

         if (left_ref == ref) {
             *mx = A[0];
             *my = A[1];

             return;
         }
     }
 
     //RARE
     pred_motion(h, n, 4, list, ref, mx, my);
 }
 
 /**

  * Get the directionally predicted 8x16 MV.

  * @param n the block index
  * @param mx the x component of the predicted motion vector
  * @param my the y component of the predicted motion vector
  */

 static av_always_inline void pred_8x16_motion(H264Context *const h,
                                               int n, int list, int ref,
                                               int *const mx, int *const my)
 {
     if (n == 0) {
         const int left_ref     = h->ref_cache[list][scan8[0] - 1];
         const int16_t *const A = h->mv_cache[list][scan8[0] - 1];
 

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

 
         if (left_ref == ref) {
             *mx = A[0];
             *my = A[1];

             return;
         }

     } else {
         const int16_t *C;

         int diagonal_ref;
 

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

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

 #define FIX_MV_MBAFF(type, refn, mvn, idx)      \

     if (FRAME_MBAFF(h)) {                       \

         if (MB_FIELD(h)) {                      \

             if (!IS_INTERLACED(type)) {         \
                 refn <<= 1;                     \
                 AV_COPY32(mvbuf[idx], mvn);     \
                 mvbuf[idx][1] /= 2;             \
                 mvn = mvbuf[idx];               \
             }                                   \
         } else {                                \
             if (IS_INTERLACED(type)) {          \
                 refn >>= 1;                     \
                 AV_COPY32(mvbuf[idx], mvn);     \
                 mvbuf[idx][1] <<= 1;            \
                 mvn = mvbuf[idx];               \
             }                                   \
         }                                       \

     }

 static av_always_inline void pred_pskip_motion(H264Context *const h)
 {
     DECLARE_ALIGNED(4, static const int16_t, zeromv)[2] = { 0 };

     DECLARE_ALIGNED(4, int16_t, mvbuf)[3][2];

     int8_t *ref     = h->cur_pic.ref_index[0];
     int16_t(*mv)[2] = h->cur_pic.motion_val[0];

     int top_ref, left_ref, diagonal_ref, match_count, mx, my;

     const int16_t *A, *B, *C;
     int b_stride = h->b_stride;
 

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

     /* To avoid doing an entire fill_decode_caches, we inline the relevant
      * parts here.
      * FIXME: this is a partial duplicate of the logic in fill_decode_caches,
      * but it's faster this way.  Is there a way to avoid this duplication?

      */

     if (USES_LIST(h->left_type[LTOP], 0)) {
         left_ref = ref[4 * h->left_mb_xy[LTOP] + 1 + (h->left_block[0] & ~1)];
         A = mv[h->mb2b_xy[h->left_mb_xy[LTOP]] + 3 + b_stride * h->left_block[0]];

         FIX_MV_MBAFF(h->left_type[LTOP], left_ref, A, 0);

         if (!(left_ref | AV_RN32A(A)))

             goto zeromv;

     } else if (h->left_type[LTOP]) {

         left_ref = LIST_NOT_USED;

         A        = zeromv;
     } else {

         goto zeromv;

     }

     if (USES_LIST(h->top_type, 0)) {
         top_ref = ref[4 * h->top_mb_xy + 2];
         B       = mv[h->mb2b_xy[h->top_mb_xy] + 3 * b_stride];

         FIX_MV_MBAFF(h->top_type, top_ref, B, 1);

         if (!(top_ref | AV_RN32A(B)))

             goto zeromv;

     } else if (h->top_type) {

         top_ref = LIST_NOT_USED;

         B       = zeromv;
     } else {

         goto zeromv;

     }
 

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

     if (USES_LIST(h->topright_type, 0)) {
         diagonal_ref = ref[4 * h->topright_mb_xy + 2];
         C = mv[h->mb2b_xy[h->topright_mb_xy] + 3 * b_stride];

         FIX_MV_MBAFF(h->topright_type, diagonal_ref, C, 2);

     } else if (h->topright_type) {

         diagonal_ref = LIST_NOT_USED;
         C = zeromv;

     } else {
         if (USES_LIST(h->topleft_type, 0)) {
             diagonal_ref = ref[4 * h->topleft_mb_xy + 1 +
                                (h->topleft_partition & 2)];
             C = mv[h->mb2b_xy[h->topleft_mb_xy] + 3 + b_stride +
                    (h->topleft_partition & 2 * b_stride)];

             FIX_MV_MBAFF(h->topleft_type, diagonal_ref, C, 2);

         } else if (h->topleft_type) {

             diagonal_ref = LIST_NOT_USED;

             C            = zeromv;
         } else {

             diagonal_ref = PART_NOT_AVAILABLE;

             C            = zeromv;

         }

     }
 

     match_count = !diagonal_ref + !top_ref + !left_ref;

     tprintf(h->avctx, "pred_pskip_motion match_count=%d\n", match_count);

     if (match_count > 1) {

         mx = mid_pred(A[0], B[0], C[0]);
         my = mid_pred(A[1], B[1], C[1]);

     } else if (match_count == 1) {
         if (!left_ref) {

             mx = A[0];
             my = A[1];

         } else if (!top_ref) {

             mx = B[0];
             my = B[1];

         } else {

             mx = C[0];
             my = C[1];

         }

     } else {

         mx = mid_pred(A[0], B[0], C[0]);
         my = mid_pred(A[1], B[1], C[1]);

     }

     fill_rectangle(h->mv_cache[0][scan8[0]], 4, 4, 8, pack16to32(mx, my), 4);

     return;

 zeromv:

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

     return;
 }

 static void fill_decode_neighbors(H264Context *h, int mb_type)
 {
     const int mb_xy = h->mb_xy;

     int topleft_xy, top_xy, topright_xy, left_xy[LEFT_MBS];

     static const uint8_t left_block_options[4][32] = {
         { 0, 1, 2, 3, 7, 10, 8, 11, 3 + 0 * 4, 3 + 1 * 4, 3 + 2 * 4, 3 + 3 * 4, 1 + 4 * 4, 1 + 8 * 4, 1 + 5 * 4, 1 + 9 * 4 },
         { 2, 2, 3, 3, 8, 11, 8, 11, 3 + 2 * 4, 3 + 2 * 4, 3 + 3 * 4, 3 + 3 * 4, 1 + 5 * 4, 1 + 9 * 4, 1 + 5 * 4, 1 + 9 * 4 },
         { 0, 0, 1, 1, 7, 10, 7, 10, 3 + 0 * 4, 3 + 0 * 4, 3 + 1 * 4, 3 + 1 * 4, 1 + 4 * 4, 1 + 8 * 4, 1 + 4 * 4, 1 + 8 * 4 },
         { 0, 2, 0, 2, 7, 10, 7, 10, 3 + 0 * 4, 3 + 2 * 4, 3 + 0 * 4, 3 + 2 * 4, 1 + 4 * 4, 1 + 8 * 4, 1 + 4 * 4, 1 + 8 * 4 }

     };
 

     h->topleft_partition = -1;

     top_xy = mb_xy - (h->mb_stride << MB_FIELD(h));

 
     /* Wow, what a mess, why didn't they simplify the interlacing & intra
      * stuff, I can't imagine that these complex rules are worth it. */
 

     topleft_xy    = top_xy - 1;
     topright_xy   = top_xy + 1;
     left_xy[LBOT] = left_xy[LTOP] = mb_xy - 1;

     h->left_block = left_block_options[0];

     if (FRAME_MBAFF(h)) {

         const int left_mb_field_flag = IS_INTERLACED(h->cur_pic.mb_type[mb_xy - 1]);

         const int curr_mb_field_flag = IS_INTERLACED(mb_type);

         if (h->mb_y & 1) {

             if (left_mb_field_flag != curr_mb_field_flag) {

                 left_xy[LBOT] = left_xy[LTOP] = mb_xy - h->mb_stride - 1;

                 if (curr_mb_field_flag) {

                     left_xy[LBOT] += h->mb_stride;

                     h->left_block  = left_block_options[3];

                 } else {

                     topleft_xy += h->mb_stride;

                     /* take top left mv from the middle of the mb, as opposed
                      * to all other modes which use the bottom right partition */

                     h->topleft_partition = 0;

                     h->left_block        = left_block_options[1];

                 }
             }

         } else {
             if (curr_mb_field_flag) {

                 topleft_xy  += h->mb_stride & (((h->cur_pic.mb_type[top_xy - 1] >> 7) & 1) - 1);
                 topright_xy += h->mb_stride & (((h->cur_pic.mb_type[top_xy + 1] >> 7) & 1) - 1);
                 top_xy      += h->mb_stride & (((h->cur_pic.mb_type[top_xy]     >> 7) & 1) - 1);

             }
             if (left_mb_field_flag != curr_mb_field_flag) {
                 if (curr_mb_field_flag) {

                     left_xy[LBOT] += h->mb_stride;

                     h->left_block  = left_block_options[3];

                 } else {
                     h->left_block = left_block_options[2];
                 }
             }
         }
     }
 

     h->topleft_mb_xy    = topleft_xy;
     h->top_mb_xy        = top_xy;
     h->topright_mb_xy   = topright_xy;

     h->left_mb_xy[LTOP] = left_xy[LTOP];
     h->left_mb_xy[LBOT] = left_xy[LBOT];
     //FIXME do we need all in the context?
 

     h->topleft_type    = h->cur_pic.mb_type[topleft_xy];
     h->top_type        = h->cur_pic.mb_type[top_xy];
     h->topright_type   = h->cur_pic.mb_type[topright_xy];
     h->left_type[LTOP] = h->cur_pic.mb_type[left_xy[LTOP]];
     h->left_type[LBOT] = h->cur_pic.mb_type[left_xy[LBOT]];

     if (FMO) {
         if (h->slice_table[topleft_xy] != h->slice_num)
             h->topleft_type = 0;
         if (h->slice_table[top_xy] != h->slice_num)
             h->top_type = 0;
         if (h->slice_table[left_xy[LTOP]] != h->slice_num)
             h->left_type[LTOP] = h->left_type[LBOT] = 0;
     } else {
         if (h->slice_table[topleft_xy] != h->slice_num) {

             h->topleft_type = 0;

             if (h->slice_table[top_xy] != h->slice_num)
                 h->top_type = 0;
             if (h->slice_table[left_xy[LTOP]] != h->slice_num)
                 h->left_type[LTOP] = h->left_type[LBOT] = 0;

         }
     }

     if (h->slice_table[topright_xy] != h->slice_num)
         h->topright_type = 0;

 }
 

 static void fill_decode_caches(H264Context *h, int mb_type)
 {

     int topleft_xy, top_xy, topright_xy, left_xy[LEFT_MBS];
     int topleft_type, top_type, topright_type, left_type[LEFT_MBS];

     const uint8_t *left_block = h->left_block;

     int i;
     uint8_t *nnz;
     uint8_t *nnz_cache;
 

     topleft_xy      = h->topleft_mb_xy;
     top_xy          = h->top_mb_xy;
     topright_xy     = h->topright_mb_xy;
     left_xy[LTOP]   = h->left_mb_xy[LTOP];
     left_xy[LBOT]   = h->left_mb_xy[LBOT];
     topleft_type    = h->topleft_type;
     top_type        = h->top_type;
     topright_type   = h->topright_type;
     left_type[LTOP] = h->left_type[LTOP];
     left_type[LBOT] = h->left_type[LBOT];
 
     if (!IS_SKIP(mb_type)) {
         if (IS_INTRA(mb_type)) {
             int type_mask = h->pps.constrained_intra_pred ? IS_INTRA(-1) : -1;
             h->topleft_samples_available      =
                 h->top_samples_available      =
                     h->left_samples_available = 0xFFFF;
             h->topright_samples_available     = 0xEEEA;
 
             if (!(top_type & type_mask)) {
                 h->topleft_samples_available  = 0xB3FF;
                 h->top_samples_available      = 0x33FF;
                 h->topright_samples_available = 0x26EA;

             }

             if (IS_INTERLACED(mb_type) != IS_INTERLACED(left_type[LTOP])) {
                 if (IS_INTERLACED(mb_type)) {
                     if (!(left_type[LTOP] & type_mask)) {
                         h->topleft_samples_available &= 0xDFFF;
                         h->left_samples_available    &= 0x5FFF;

                     }

                     if (!(left_type[LBOT] & type_mask)) {
                         h->topleft_samples_available &= 0xFF5F;
                         h->left_samples_available    &= 0xFF5F;

                     }

                 } else {

                     int left_typei = h->cur_pic.mb_type[left_xy[LTOP] + h->mb_stride];

                     av_assert2(left_xy[LTOP] == left_xy[LBOT]);

                     if (!((left_typei & type_mask) && (left_type[LTOP] & type_mask))) {
                         h->topleft_samples_available &= 0xDF5F;
                         h->left_samples_available    &= 0x5F5F;

                     }
                 }

             } else {
                 if (!(left_type[LTOP] & type_mask)) {
                     h->topleft_samples_available &= 0xDF5F;
                     h->left_samples_available    &= 0x5F5F;

                 }
             }
 

             if (!(topleft_type & type_mask))
                 h->topleft_samples_available &= 0x7FFF;

             if (!(topright_type & type_mask))
                 h->topright_samples_available &= 0xFBFF;

             if (IS_INTRA4x4(mb_type)) {
                 if (IS_INTRA4x4(top_type)) {
                     AV_COPY32(h->intra4x4_pred_mode_cache + 4 + 8 * 0, h->intra4x4_pred_mode + h->mb2br_xy[top_xy]);
                 } else {
                     h->intra4x4_pred_mode_cache[4 + 8 * 0] =
                     h->intra4x4_pred_mode_cache[5 + 8 * 0] =
                     h->intra4x4_pred_mode_cache[6 + 8 * 0] =
                     h->intra4x4_pred_mode_cache[7 + 8 * 0] = 2 - 3 * !(top_type & type_mask);

                 }

                 for (i = 0; i < 2; i++) {
                     if (IS_INTRA4x4(left_type[LEFT(i)])) {
                         int8_t *mode = h->intra4x4_pred_mode + h->mb2br_xy[left_xy[LEFT(i)]];
                         h->intra4x4_pred_mode_cache[3 + 8 * 1 + 2 * 8 * i] = mode[6 - left_block[0 + 2 * i]];
                         h->intra4x4_pred_mode_cache[3 + 8 * 2 + 2 * 8 * i] = mode[6 - left_block[1 + 2 * i]];
                     } else {
                         h->intra4x4_pred_mode_cache[3 + 8 * 1 + 2 * 8 * i] =
                         h->intra4x4_pred_mode_cache[3 + 8 * 2 + 2 * 8 * i] = 2 - 3 * !(left_type[LEFT(i)] & type_mask);

                     }
                 }
             }
         }
 

         /*
          * 0 . T T. T T T T
          * 1 L . .L . . . .
          * 2 L . .L . . . .
          * 3 . T TL . . . .
          * 4 L . .L . . . .
          * 5 L . .. . . . .
          */
         /* FIXME: constraint_intra_pred & partitioning & nnz
          * (let us hope this is just a typo in the spec) */
         nnz_cache = h->non_zero_count_cache;
         if (top_type) {
             nnz = h->non_zero_count[top_xy];
             AV_COPY32(&nnz_cache[4 + 8 * 0], &nnz[4 * 3]);

             if (!h->chroma_y_shift) {

                 AV_COPY32(&nnz_cache[4 + 8 *  5], &nnz[4 *  7]);
                 AV_COPY32(&nnz_cache[4 + 8 * 10], &nnz[4 * 11]);
             } else {
                 AV_COPY32(&nnz_cache[4 + 8 *  5], &nnz[4 * 5]);
                 AV_COPY32(&nnz_cache[4 + 8 * 10], &nnz[4 * 9]);
             }
         } else {

             uint32_t top_empty = CABAC(h) && !IS_INTRA(mb_type) ? 0 : 0x40404040;

             AV_WN32A(&nnz_cache[4 + 8 *  0], top_empty);
             AV_WN32A(&nnz_cache[4 + 8 *  5], top_empty);
             AV_WN32A(&nnz_cache[4 + 8 * 10], top_empty);

         }
 

         for (i = 0; i < 2; i++) {
             if (left_type[LEFT(i)]) {
                 nnz = h->non_zero_count[left_xy[LEFT(i)]];
                 nnz_cache[3 + 8 * 1 + 2 * 8 * i] = nnz[left_block[8 + 0 + 2 * i]];
                 nnz_cache[3 + 8 * 2 + 2 * 8 * i] = nnz[left_block[8 + 1 + 2 * i]];

                 if (CHROMA444(h)) {

                     nnz_cache[3 + 8 *  6 + 2 * 8 * i] = nnz[left_block[8 + 0 + 2 * i] + 4 * 4];
                     nnz_cache[3 + 8 *  7 + 2 * 8 * i] = nnz[left_block[8 + 1 + 2 * i] + 4 * 4];
                     nnz_cache[3 + 8 * 11 + 2 * 8 * i] = nnz[left_block[8 + 0 + 2 * i] + 8 * 4];
                     nnz_cache[3 + 8 * 12 + 2 * 8 * i] = nnz[left_block[8 + 1 + 2 * i] + 8 * 4];

                 } else if (CHROMA422(h)) {

                     nnz_cache[3 + 8 *  6 + 2 * 8 * i] = nnz[left_block[8 + 0 + 2 * i] - 2 + 4 * 4];
                     nnz_cache[3 + 8 *  7 + 2 * 8 * i] = nnz[left_block[8 + 1 + 2 * i] - 2 + 4 * 4];
                     nnz_cache[3 + 8 * 11 + 2 * 8 * i] = nnz[left_block[8 + 0 + 2 * i] - 2 + 8 * 4];
                     nnz_cache[3 + 8 * 12 + 2 * 8 * i] = nnz[left_block[8 + 1 + 2 * i] - 2 + 8 * 4];
                 } else {
                     nnz_cache[3 + 8 *  6 + 8 * i] = nnz[left_block[8 + 4 + 2 * i]];
                     nnz_cache[3 + 8 * 11 + 8 * i] = nnz[left_block[8 + 5 + 2 * i]];
                 }
             } else {
                 nnz_cache[3 + 8 *  1 + 2 * 8 * i] =
                 nnz_cache[3 + 8 *  2 + 2 * 8 * i] =
                 nnz_cache[3 + 8 *  6 + 2 * 8 * i] =
                 nnz_cache[3 + 8 *  7 + 2 * 8 * i] =
                 nnz_cache[3 + 8 * 11 + 2 * 8 * i] =

                 nnz_cache[3 + 8 * 12 + 2 * 8 * i] = CABAC(h) && !IS_INTRA(mb_type) ? 0 : 64;

             }
         }
 

         if (CABAC(h)) {

             // top_cbp
             if (top_type)
                 h->top_cbp = h->cbp_table[top_xy];
             else
                 h->top_cbp = IS_INTRA(mb_type) ? 0x7CF : 0x00F;
             // left_cbp
             if (left_type[LTOP]) {
                 h->left_cbp =   (h->cbp_table[left_xy[LTOP]] & 0x7F0) |
                                ((h->cbp_table[left_xy[LTOP]] >> (left_block[0] & (~1))) & 2) |
                               (((h->cbp_table[left_xy[LBOT]] >> (left_block[2] & (~1))) & 2) << 2);
             } else {
                 h->left_cbp = IS_INTRA(mb_type) ? 0x7CF : 0x00F;
             }

         }
     }
 

     if (IS_INTER(mb_type) || (IS_DIRECT(mb_type) && h->direct_spatial_mv_pred)) {

         int list;
         int b_stride = h->b_stride;

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

             int8_t *ref_cache = &h->ref_cache[list][scan8[0]];

             int8_t *ref       = h->cur_pic.ref_index[list];

             int16_t(*mv_cache)[2] = &h->mv_cache[list][scan8[0]];

             int16_t(*mv)[2]       = h->cur_pic.motion_val[list];

             if (!USES_LIST(mb_type, list))

                 continue;

             av_assert2(!(IS_DIRECT(mb_type) && !h->direct_spatial_mv_pred));

             if (USES_LIST(top_type, list)) {
                 const int b_xy = h->mb2b_xy[top_xy] + 3 * b_stride;
                 AV_COPY128(mv_cache[0 - 1 * 8], mv[b_xy + 0]);
                 ref_cache[0 - 1 * 8] =
                 ref_cache[1 - 1 * 8] = ref[4 * top_xy + 2];
                 ref_cache[2 - 1 * 8] =
                 ref_cache[3 - 1 * 8] = ref[4 * top_xy + 3];
             } else {
                 AV_ZERO128(mv_cache[0 - 1 * 8]);
                 AV_WN32A(&ref_cache[0 - 1 * 8],
                          ((top_type ? LIST_NOT_USED : PART_NOT_AVAILABLE) & 0xFF) * 0x01010101u);

             }
 

             if (mb_type & (MB_TYPE_16x8 | MB_TYPE_8x8)) {
                 for (i = 0; i < 2; i++) {
                     int cache_idx = -1 + i * 2 * 8;
                     if (USES_LIST(left_type[LEFT(i)], list)) {
                         const int b_xy  = h->mb2b_xy[left_xy[LEFT(i)]] + 3;
                         const int b8_xy = 4 * left_xy[LEFT(i)] + 1;
                         AV_COPY32(mv_cache[cache_idx],
                                   mv[b_xy + b_stride * left_block[0 + i * 2]]);
                         AV_COPY32(mv_cache[cache_idx + 8],
                                   mv[b_xy + b_stride * left_block[1 + i * 2]]);
                         ref_cache[cache_idx]     = ref[b8_xy + (left_block[0 + i * 2] & ~1)];
                         ref_cache[cache_idx + 8] = ref[b8_xy + (left_block[1 + i * 2] & ~1)];
                     } else {
                         AV_ZERO32(mv_cache[cache_idx]);
                         AV_ZERO32(mv_cache[cache_idx + 8]);
                         ref_cache[cache_idx]     =
                         ref_cache[cache_idx + 8] = (left_type[LEFT(i)]) ? LIST_NOT_USED
                                                                         : PART_NOT_AVAILABLE;
                     }

                 }

             } else {
                 if (USES_LIST(left_type[LTOP], list)) {
                     const int b_xy  = h->mb2b_xy[left_xy[LTOP]] + 3;
                     const int b8_xy = 4 * left_xy[LTOP] + 1;
                     AV_COPY32(mv_cache[-1], mv[b_xy + b_stride * left_block[0]]);
                     ref_cache[-1] = ref[b8_xy + (left_block[0] & ~1)];
                 } else {

                     AV_ZERO32(mv_cache[-1]);

                     ref_cache[-1] = left_type[LTOP] ? LIST_NOT_USED
                                                     : PART_NOT_AVAILABLE;

                 }
             }
 

             if (USES_LIST(topright_type, list)) {
                 const int b_xy = h->mb2b_xy[topright_xy] + 3 * b_stride;
                 AV_COPY32(mv_cache[4 - 1 * 8], mv[b_xy]);
                 ref_cache[4 - 1 * 8] = ref[4 * topright_xy + 2];
             } else {
                 AV_ZERO32(mv_cache[4 - 1 * 8]);
                 ref_cache[4 - 1 * 8] = topright_type ? LIST_NOT_USED
                                                      : PART_NOT_AVAILABLE;

             }

             if(ref_cache[2 - 1*8] < 0 || ref_cache[4 - 1*8] < 0){

                 if (USES_LIST(topleft_type, list)) {
                     const int b_xy  = h->mb2b_xy[topleft_xy] + 3 + b_stride +
                                       (h->topleft_partition & 2 * b_stride);
                     const int b8_xy = 4 * topleft_xy + 1 + (h->topleft_partition & 2);
                     AV_COPY32(mv_cache[-1 - 1 * 8], mv[b_xy]);
                     ref_cache[-1 - 1 * 8] = ref[b8_xy];
                 } else {
                     AV_ZERO32(mv_cache[-1 - 1 * 8]);
                     ref_cache[-1 - 1 * 8] = topleft_type ? LIST_NOT_USED
                                                          : PART_NOT_AVAILABLE;

                 }
             }
 

             if ((mb_type & (MB_TYPE_SKIP | MB_TYPE_DIRECT2)) && !FRAME_MBAFF(h))

                 continue;
 

             if (!(mb_type & (MB_TYPE_SKIP | MB_TYPE_DIRECT2))) {
                 uint8_t(*mvd_cache)[2]   = &h->mvd_cache[list][scan8[0]];
                 uint8_t(*mvd)[2]         = h->mvd_table[list];
                 ref_cache[2 + 8 * 0] =
                 ref_cache[2 + 8 * 2] = PART_NOT_AVAILABLE;
                 AV_ZERO32(mv_cache[2 + 8 * 0]);
                 AV_ZERO32(mv_cache[2 + 8 * 2]);
 

                 if (CABAC(h)) {

                     if (USES_LIST(top_type, list)) {
                         const int b_xy = h->mb2br_xy[top_xy];
                         AV_COPY64(mvd_cache[0 - 1 * 8], mvd[b_xy + 0]);
                     } else {
                         AV_ZERO64(mvd_cache[0 - 1 * 8]);

                     }

                     if (USES_LIST(left_type[LTOP], list)) {
                         const int b_xy = h->mb2br_xy[left_xy[LTOP]] + 6;
                         AV_COPY16(mvd_cache[-1 + 0 * 8], mvd[b_xy - left_block[0]]);
                         AV_COPY16(mvd_cache[-1 + 1 * 8], mvd[b_xy - left_block[1]]);
                     } else {
                         AV_ZERO16(mvd_cache[-1 + 0 * 8]);
                         AV_ZERO16(mvd_cache[-1 + 1 * 8]);

                     }

                     if (USES_LIST(left_type[LBOT], list)) {
                         const int b_xy = h->mb2br_xy[left_xy[LBOT]] + 6;
                         AV_COPY16(mvd_cache[-1 + 2 * 8], mvd[b_xy - left_block[2]]);
                         AV_COPY16(mvd_cache[-1 + 3 * 8], mvd[b_xy - left_block[3]]);
                     } else {
                         AV_ZERO16(mvd_cache[-1 + 2 * 8]);
                         AV_ZERO16(mvd_cache[-1 + 3 * 8]);

                     }

                     AV_ZERO16(mvd_cache[2 + 8 * 0]);
                     AV_ZERO16(mvd_cache[2 + 8 * 2]);
                     if (h->slice_type_nos == AV_PICTURE_TYPE_B) {

                         uint8_t *direct_cache = &h->direct_cache[scan8[0]];
                         uint8_t *direct_table = h->direct_table;

                         fill_rectangle(direct_cache, 4, 4, 8, MB_TYPE_16x16 >> 1, 1);
 
                         if (IS_DIRECT(top_type)) {
                             AV_WN32A(&direct_cache[-1 * 8],
                                      0x01010101u * (MB_TYPE_DIRECT2 >> 1));
                         } else if (IS_8X8(top_type)) {
                             int b8_xy = 4 * top_xy;
                             direct_cache[0 - 1 * 8] = direct_table[b8_xy + 2];
                             direct_cache[2 - 1 * 8] = direct_table[b8_xy + 3];
                         } else {
                             AV_WN32A(&direct_cache[-1 * 8],
                                      0x01010101 * (MB_TYPE_16x16 >> 1));

                         }
 

                         if (IS_DIRECT(left_type[LTOP]))
                             direct_cache[-1 + 0 * 8] = MB_TYPE_DIRECT2 >> 1;
                         else if (IS_8X8(left_type[LTOP]))
                             direct_cache[-1 + 0 * 8] = direct_table[4 * left_xy[LTOP] + 1 + (left_block[0] & ~1)];

                         else

                             direct_cache[-1 + 0 * 8] = MB_TYPE_16x16 >> 1;

                         if (IS_DIRECT(left_type[LBOT]))
                             direct_cache[-1 + 2 * 8] = MB_TYPE_DIRECT2 >> 1;
                         else if (IS_8X8(left_type[LBOT]))
                             direct_cache[-1 + 2 * 8] = direct_table[4 * left_xy[LBOT] + 1 + (left_block[2] & ~1)];

                         else

                             direct_cache[-1 + 2 * 8] = MB_TYPE_16x16 >> 1;

                     }
                 }
             }

 
 #define MAP_MVS                                                         \
     MAP_F2F(scan8[0] - 1 - 1 * 8, topleft_type)                         \
     MAP_F2F(scan8[0] + 0 - 1 * 8, top_type)                             \
     MAP_F2F(scan8[0] + 1 - 1 * 8, top_type)                             \
     MAP_F2F(scan8[0] + 2 - 1 * 8, top_type)                             \
     MAP_F2F(scan8[0] + 3 - 1 * 8, top_type)                             \
     MAP_F2F(scan8[0] + 4 - 1 * 8, topright_type)                        \
     MAP_F2F(scan8[0] - 1 + 0 * 8, left_type[LTOP])                      \
     MAP_F2F(scan8[0] - 1 + 1 * 8, left_type[LTOP])                      \
     MAP_F2F(scan8[0] - 1 + 2 * 8, left_type[LBOT])                      \
     MAP_F2F(scan8[0] - 1 + 3 * 8, left_type[LBOT])
 

             if (FRAME_MBAFF(h)) {

                 if (MB_FIELD(h)) {

 
 #define MAP_F2F(idx, mb_type)                                           \
     if (!IS_INTERLACED(mb_type) && h->ref_cache[list][idx] >= 0) {      \
         h->ref_cache[list][idx]    <<= 1;                               \
         h->mv_cache[list][idx][1]   /= 2;                               \
         h->mvd_cache[list][idx][1] >>= 1;                               \
     }
 

                     MAP_MVS

                 } else {
 

 #undef MAP_F2F

 #define MAP_F2F(idx, mb_type)                                           \
     if (IS_INTERLACED(mb_type) && h->ref_cache[list][idx] >= 0) {       \
         h->ref_cache[list][idx]    >>= 1;                               \
         h->mv_cache[list][idx][1]  <<= 1;                               \
         h->mvd_cache[list][idx][1] <<= 1;                               \
     }
 

                     MAP_MVS
 #undef MAP_F2F
                 }
             }
         }
     }
 

     h->neighbor_transform_size = !!IS_8x8DCT(top_type) + !!IS_8x8DCT(left_type[LTOP]);

 }
 

 /**
  * decodes a P_SKIP or B_SKIP macroblock
  */

 static void av_unused decode_mb_skip(H264Context *h)
 {
     const int mb_xy = h->mb_xy;
     int mb_type     = 0;

 
     memset(h->non_zero_count[mb_xy], 0, 48);
 

     if (MB_FIELD(h))

         mb_type |= MB_TYPE_INTERLACED;

     if (h->slice_type_nos == AV_PICTURE_TYPE_B) {

         // just for fill_caches. pred_direct_motion will set the real mb_type

         mb_type |= MB_TYPE_L0L1 | MB_TYPE_DIRECT2 | MB_TYPE_SKIP;
         if (h->direct_spatial_mv_pred) {

             fill_decode_neighbors(h, mb_type);

             fill_decode_caches(h, mb_type); //FIXME check what is needed and what not ...

         }
         ff_h264_pred_direct_motion(h, &mb_type);

         mb_type |= MB_TYPE_SKIP;
     } else {
         mb_type |= MB_TYPE_16x16 | MB_TYPE_P0L0 | MB_TYPE_P1L0 | MB_TYPE_SKIP;

 
         fill_decode_neighbors(h, mb_type);
         pred_pskip_motion(h);
     }
 
     write_back_motion(h, mb_type);

     h->cur_pic.mb_type[mb_xy]      = mb_type;
     h->cur_pic.qscale_table[mb_xy] = h->qscale;

     h->slice_table[mb_xy]            = h->slice_num;
     h->prev_mb_skipped               = 1;

 }
 

 #endif /* AVCODEC_H264_MVPRED_H */