| /* | 
 |  * Copyright (c) 2016, Alliance for Open Media. All rights reserved. | 
 |  * | 
 |  * This source code is subject to the terms of the BSD 2 Clause License and | 
 |  * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License | 
 |  * was not distributed with this source code in the LICENSE file, you can | 
 |  * obtain it at www.aomedia.org/license/software. If the Alliance for Open | 
 |  * Media Patent License 1.0 was not distributed with this source code in the | 
 |  * PATENTS file, you can obtain it at www.aomedia.org/license/patent. | 
 |  */ | 
 |  | 
 | #include <stdlib.h> | 
 |  | 
 | #include "av1/common/mvref_common.h" | 
 | #include "av1/common/warped_motion.h" | 
 |  | 
 | // Although we assign 32 bit integers, all the values are strictly under 14 | 
 | // bits. | 
 | static const int div_mult[32] = { 0,    16384, 8192, 5461, 4096, 3276, 2730, | 
 |                                   2340, 2048,  1820, 1638, 1489, 1365, 1260, | 
 |                                   1170, 1092,  1024, 963,  910,  862,  819, | 
 |                                   780,  744,   712,  682,  655,  630,  606, | 
 |                                   585,  564,   546,  528 }; | 
 |  | 
 | // TODO(jingning): Consider the use of lookup table for (num / den) | 
 | // altogether. | 
 | void av1_get_mv_projection(MV *output, MV ref, int num, int den) { | 
 |   den = AOMMIN(den, MAX_FRAME_DISTANCE); | 
 |   num = num > 0 ? AOMMIN(num, MAX_FRAME_DISTANCE) | 
 |                 : AOMMAX(num, -MAX_FRAME_DISTANCE); | 
 |   const int mv_row = | 
 |       ROUND_POWER_OF_TWO_SIGNED(ref.row * num * div_mult[den], 14); | 
 |   const int mv_col = | 
 |       ROUND_POWER_OF_TWO_SIGNED(ref.col * num * div_mult[den], 14); | 
 |   const int clamp_max = MV_UPP - 1; | 
 |   const int clamp_min = MV_LOW + 1; | 
 |   output->row = (int16_t)clamp(mv_row, clamp_min, clamp_max); | 
 |   output->col = (int16_t)clamp(mv_col, clamp_min, clamp_max); | 
 | } | 
 |  | 
 | void av1_copy_frame_mvs(const AV1_COMMON *const cm, | 
 |                         const MB_MODE_INFO *const mi, int mi_row, int mi_col, | 
 |                         int x_mis, int y_mis) { | 
 |   const int frame_mvs_stride = ROUND_POWER_OF_TWO(cm->mi_params.mi_cols, 1); | 
 |   MV_REF *frame_mvs = | 
 |       cm->cur_frame->mvs + (mi_row >> 1) * frame_mvs_stride + (mi_col >> 1); | 
 |   x_mis = ROUND_POWER_OF_TWO(x_mis, 1); | 
 |   y_mis = ROUND_POWER_OF_TWO(y_mis, 1); | 
 |   int w, h; | 
 |  | 
 |   for (h = 0; h < y_mis; h++) { | 
 |     MV_REF *mv = frame_mvs; | 
 |     for (w = 0; w < x_mis; w++) { | 
 |       mv->ref_frame = NONE_FRAME; | 
 |       mv->mv.as_int = 0; | 
 |  | 
 |       for (int idx = 0; idx < 2; ++idx) { | 
 |         MV_REFERENCE_FRAME ref_frame = mi->ref_frame[idx]; | 
 |         if (ref_frame > INTRA_FRAME) { | 
 |           int8_t ref_idx = cm->ref_frame_side[ref_frame]; | 
 |           if (ref_idx) continue; | 
 |           if ((abs(mi->mv[idx].as_mv.row) > REFMVS_LIMIT) || | 
 |               (abs(mi->mv[idx].as_mv.col) > REFMVS_LIMIT)) | 
 |             continue; | 
 |           mv->ref_frame = ref_frame; | 
 |           mv->mv.as_int = mi->mv[idx].as_int; | 
 |         } | 
 |       } | 
 |       mv++; | 
 |     } | 
 |     frame_mvs += frame_mvs_stride; | 
 |   } | 
 | } | 
 |  | 
 | static inline void add_ref_mv_candidate( | 
 |     const MB_MODE_INFO *const candidate, const MV_REFERENCE_FRAME rf[2], | 
 |     uint8_t *refmv_count, uint8_t *ref_match_count, uint8_t *newmv_count, | 
 |     CANDIDATE_MV *ref_mv_stack, uint16_t *ref_mv_weight, | 
 |     int_mv *gm_mv_candidates, const WarpedMotionParams *gm_params, | 
 |     uint16_t weight) { | 
 |   if (!is_inter_block(candidate)) return; | 
 |   assert(weight % 2 == 0); | 
 |   int index, ref; | 
 |  | 
 |   if (rf[1] == NONE_FRAME) { | 
 |     // single reference frame | 
 |     for (ref = 0; ref < 2; ++ref) { | 
 |       if (candidate->ref_frame[ref] == rf[0]) { | 
 |         const int is_gm_block = | 
 |             is_global_mv_block(candidate, gm_params[rf[0]].wmtype); | 
 |         const int_mv this_refmv = | 
 |             is_gm_block ? gm_mv_candidates[0] : get_block_mv(candidate, ref); | 
 |         for (index = 0; index < *refmv_count; ++index) { | 
 |           if (ref_mv_stack[index].this_mv.as_int == this_refmv.as_int) { | 
 |             ref_mv_weight[index] += weight; | 
 |             break; | 
 |           } | 
 |         } | 
 |  | 
 |         // Add a new item to the list. | 
 |         if (index == *refmv_count && *refmv_count < MAX_REF_MV_STACK_SIZE) { | 
 |           ref_mv_stack[index].this_mv = this_refmv; | 
 |           ref_mv_weight[index] = weight; | 
 |           ++(*refmv_count); | 
 |         } | 
 |         if (have_newmv_in_inter_mode(candidate->mode)) ++*newmv_count; | 
 |         ++*ref_match_count; | 
 |       } | 
 |     } | 
 |   } else { | 
 |     // compound reference frame | 
 |     if (candidate->ref_frame[0] == rf[0] && candidate->ref_frame[1] == rf[1]) { | 
 |       int_mv this_refmv[2]; | 
 |  | 
 |       for (ref = 0; ref < 2; ++ref) { | 
 |         if (is_global_mv_block(candidate, gm_params[rf[ref]].wmtype)) | 
 |           this_refmv[ref] = gm_mv_candidates[ref]; | 
 |         else | 
 |           this_refmv[ref] = get_block_mv(candidate, ref); | 
 |       } | 
 |  | 
 |       for (index = 0; index < *refmv_count; ++index) { | 
 |         if ((ref_mv_stack[index].this_mv.as_int == this_refmv[0].as_int) && | 
 |             (ref_mv_stack[index].comp_mv.as_int == this_refmv[1].as_int)) { | 
 |           ref_mv_weight[index] += weight; | 
 |           break; | 
 |         } | 
 |       } | 
 |  | 
 |       // Add a new item to the list. | 
 |       if (index == *refmv_count && *refmv_count < MAX_REF_MV_STACK_SIZE) { | 
 |         ref_mv_stack[index].this_mv = this_refmv[0]; | 
 |         ref_mv_stack[index].comp_mv = this_refmv[1]; | 
 |         ref_mv_weight[index] = weight; | 
 |         ++(*refmv_count); | 
 |       } | 
 |       if (have_newmv_in_inter_mode(candidate->mode)) ++*newmv_count; | 
 |       ++*ref_match_count; | 
 |     } | 
 |   } | 
 | } | 
 |  | 
 | static inline void scan_row_mbmi(const AV1_COMMON *cm, const MACROBLOCKD *xd, | 
 |                                  int mi_col, const MV_REFERENCE_FRAME rf[2], | 
 |                                  int row_offset, CANDIDATE_MV *ref_mv_stack, | 
 |                                  uint16_t *ref_mv_weight, uint8_t *refmv_count, | 
 |                                  uint8_t *ref_match_count, uint8_t *newmv_count, | 
 |                                  int_mv *gm_mv_candidates, int max_row_offset, | 
 |                                  int *processed_rows) { | 
 |   int end_mi = AOMMIN(xd->width, cm->mi_params.mi_cols - mi_col); | 
 |   end_mi = AOMMIN(end_mi, mi_size_wide[BLOCK_64X64]); | 
 |   const int width_8x8 = mi_size_wide[BLOCK_8X8]; | 
 |   const int width_16x16 = mi_size_wide[BLOCK_16X16]; | 
 |   int col_offset = 0; | 
 |   // TODO(jingning): Revisit this part after cb4x4 is stable. | 
 |   if (abs(row_offset) > 1) { | 
 |     col_offset = 1; | 
 |     if ((mi_col & 0x01) && xd->width < width_8x8) --col_offset; | 
 |   } | 
 |   const int use_step_16 = (xd->width >= 16); | 
 |   MB_MODE_INFO **const candidate_mi0 = xd->mi + row_offset * xd->mi_stride; | 
 |  | 
 |   for (int i = 0; i < end_mi;) { | 
 |     const MB_MODE_INFO *const candidate = candidate_mi0[col_offset + i]; | 
 |     const int candidate_bsize = candidate->bsize; | 
 |     const int n4_w = mi_size_wide[candidate_bsize]; | 
 |     int len = AOMMIN(xd->width, n4_w); | 
 |     if (use_step_16) | 
 |       len = AOMMAX(width_16x16, len); | 
 |     else if (abs(row_offset) > 1) | 
 |       len = AOMMAX(len, width_8x8); | 
 |  | 
 |     uint16_t weight = 2; | 
 |     if (xd->width >= width_8x8 && xd->width <= n4_w) { | 
 |       uint16_t inc = AOMMIN(-max_row_offset + row_offset + 1, | 
 |                             mi_size_high[candidate_bsize]); | 
 |       // Obtain range used in weight calculation. | 
 |       weight = AOMMAX(weight, inc); | 
 |       // Update processed rows. | 
 |       *processed_rows = inc - row_offset - 1; | 
 |     } | 
 |  | 
 |     add_ref_mv_candidate(candidate, rf, refmv_count, ref_match_count, | 
 |                          newmv_count, ref_mv_stack, ref_mv_weight, | 
 |                          gm_mv_candidates, cm->global_motion, len * weight); | 
 |  | 
 |     i += len; | 
 |   } | 
 | } | 
 |  | 
 | static inline void scan_col_mbmi(const AV1_COMMON *cm, const MACROBLOCKD *xd, | 
 |                                  int mi_row, const MV_REFERENCE_FRAME rf[2], | 
 |                                  int col_offset, CANDIDATE_MV *ref_mv_stack, | 
 |                                  uint16_t *ref_mv_weight, uint8_t *refmv_count, | 
 |                                  uint8_t *ref_match_count, uint8_t *newmv_count, | 
 |                                  int_mv *gm_mv_candidates, int max_col_offset, | 
 |                                  int *processed_cols) { | 
 |   int end_mi = AOMMIN(xd->height, cm->mi_params.mi_rows - mi_row); | 
 |   end_mi = AOMMIN(end_mi, mi_size_high[BLOCK_64X64]); | 
 |   const int n8_h_8 = mi_size_high[BLOCK_8X8]; | 
 |   const int n8_h_16 = mi_size_high[BLOCK_16X16]; | 
 |   int i; | 
 |   int row_offset = 0; | 
 |   if (abs(col_offset) > 1) { | 
 |     row_offset = 1; | 
 |     if ((mi_row & 0x01) && xd->height < n8_h_8) --row_offset; | 
 |   } | 
 |   const int use_step_16 = (xd->height >= 16); | 
 |  | 
 |   for (i = 0; i < end_mi;) { | 
 |     const MB_MODE_INFO *const candidate = | 
 |         xd->mi[(row_offset + i) * xd->mi_stride + col_offset]; | 
 |     const int candidate_bsize = candidate->bsize; | 
 |     const int n4_h = mi_size_high[candidate_bsize]; | 
 |     int len = AOMMIN(xd->height, n4_h); | 
 |     if (use_step_16) | 
 |       len = AOMMAX(n8_h_16, len); | 
 |     else if (abs(col_offset) > 1) | 
 |       len = AOMMAX(len, n8_h_8); | 
 |  | 
 |     int weight = 2; | 
 |     if (xd->height >= n8_h_8 && xd->height <= n4_h) { | 
 |       int inc = AOMMIN(-max_col_offset + col_offset + 1, | 
 |                        mi_size_wide[candidate_bsize]); | 
 |       // Obtain range used in weight calculation. | 
 |       weight = AOMMAX(weight, inc); | 
 |       // Update processed cols. | 
 |       *processed_cols = inc - col_offset - 1; | 
 |     } | 
 |  | 
 |     add_ref_mv_candidate(candidate, rf, refmv_count, ref_match_count, | 
 |                          newmv_count, ref_mv_stack, ref_mv_weight, | 
 |                          gm_mv_candidates, cm->global_motion, len * weight); | 
 |  | 
 |     i += len; | 
 |   } | 
 | } | 
 |  | 
 | static inline void scan_blk_mbmi(const AV1_COMMON *cm, const MACROBLOCKD *xd, | 
 |                                  const int mi_row, const int mi_col, | 
 |                                  const MV_REFERENCE_FRAME rf[2], int row_offset, | 
 |                                  int col_offset, CANDIDATE_MV *ref_mv_stack, | 
 |                                  uint16_t *ref_mv_weight, | 
 |                                  uint8_t *ref_match_count, uint8_t *newmv_count, | 
 |                                  int_mv *gm_mv_candidates, | 
 |                                  uint8_t *refmv_count) { | 
 |   const TileInfo *const tile = &xd->tile; | 
 |   POSITION mi_pos; | 
 |  | 
 |   mi_pos.row = row_offset; | 
 |   mi_pos.col = col_offset; | 
 |  | 
 |   if (is_inside(tile, mi_col, mi_row, &mi_pos)) { | 
 |     const MB_MODE_INFO *const candidate = | 
 |         xd->mi[mi_pos.row * xd->mi_stride + mi_pos.col]; | 
 |     const int len = mi_size_wide[BLOCK_8X8]; | 
 |  | 
 |     add_ref_mv_candidate(candidate, rf, refmv_count, ref_match_count, | 
 |                          newmv_count, ref_mv_stack, ref_mv_weight, | 
 |                          gm_mv_candidates, cm->global_motion, 2 * len); | 
 |   }  // Analyze a single 8x8 block motion information. | 
 | } | 
 |  | 
 | static int has_top_right(const AV1_COMMON *cm, const MACROBLOCKD *xd, | 
 |                          int mi_row, int mi_col, int bs) { | 
 |   const int sb_mi_size = mi_size_wide[cm->seq_params->sb_size]; | 
 |   const int mask_row = mi_row & (sb_mi_size - 1); | 
 |   const int mask_col = mi_col & (sb_mi_size - 1); | 
 |  | 
 |   if (bs > mi_size_wide[BLOCK_64X64]) return 0; | 
 |  | 
 |   // In a split partition all apart from the bottom right has a top right | 
 |   int has_tr = !((mask_row & bs) && (mask_col & bs)); | 
 |  | 
 |   // bs > 0 and bs is a power of 2 | 
 |   assert(bs > 0 && !(bs & (bs - 1))); | 
 |  | 
 |   // For each 4x4 group of blocks, when the bottom right is decoded the blocks | 
 |   // to the right have not been decoded therefore the bottom right does | 
 |   // not have a top right | 
 |   while (bs < sb_mi_size) { | 
 |     if (mask_col & bs) { | 
 |       if ((mask_col & (2 * bs)) && (mask_row & (2 * bs))) { | 
 |         has_tr = 0; | 
 |         break; | 
 |       } | 
 |     } else { | 
 |       break; | 
 |     } | 
 |     bs <<= 1; | 
 |   } | 
 |  | 
 |   // In a VERTICAL or VERTICAL_4 partition, all partition before the last one | 
 |   // always have a top right (as the block above will have been decoded). | 
 |   if (xd->width < xd->height) { | 
 |     if (!xd->is_last_vertical_rect) has_tr = 1; | 
 |   } | 
 |  | 
 |   // In a HORIZONTAL or HORIZONTAL_4 partition, partitions after the first one | 
 |   // never have a top right (as the block to the right won't have been decoded). | 
 |   if (xd->width > xd->height) { | 
 |     if (!xd->is_first_horizontal_rect) has_tr = 0; | 
 |   } | 
 |  | 
 |   // The bottom left square of a Vertical A (in the old format) does | 
 |   // not have a top right as it is decoded before the right hand | 
 |   // rectangle of the partition | 
 |   if (xd->mi[0]->partition == PARTITION_VERT_A) { | 
 |     if (xd->width == xd->height) | 
 |       if (mask_row & bs) has_tr = 0; | 
 |   } | 
 |  | 
 |   return has_tr; | 
 | } | 
 |  | 
 | static int check_sb_border(const int mi_row, const int mi_col, | 
 |                            const int row_offset, const int col_offset) { | 
 |   const int sb_mi_size = mi_size_wide[BLOCK_64X64]; | 
 |   const int row = mi_row & (sb_mi_size - 1); | 
 |   const int col = mi_col & (sb_mi_size - 1); | 
 |  | 
 |   if (row + row_offset < 0 || row + row_offset >= sb_mi_size || | 
 |       col + col_offset < 0 || col + col_offset >= sb_mi_size) | 
 |     return 0; | 
 |  | 
 |   return 1; | 
 | } | 
 |  | 
 | static int add_tpl_ref_mv(const AV1_COMMON *cm, const MACROBLOCKD *xd, | 
 |                           int mi_row, int mi_col, MV_REFERENCE_FRAME ref_frame, | 
 |                           int blk_row, int blk_col, int_mv *gm_mv_candidates, | 
 |                           uint8_t *const refmv_count, | 
 |                           CANDIDATE_MV ref_mv_stack[MAX_REF_MV_STACK_SIZE], | 
 |                           uint16_t ref_mv_weight[MAX_REF_MV_STACK_SIZE], | 
 |                           int16_t *mode_context) { | 
 |   POSITION mi_pos; | 
 |   mi_pos.row = (mi_row & 0x01) ? blk_row : blk_row + 1; | 
 |   mi_pos.col = (mi_col & 0x01) ? blk_col : blk_col + 1; | 
 |  | 
 |   if (!is_inside(&xd->tile, mi_col, mi_row, &mi_pos)) return 0; | 
 |  | 
 |   const TPL_MV_REF *prev_frame_mvs = | 
 |       cm->tpl_mvs + | 
 |       ((mi_row + mi_pos.row) >> 1) * (cm->mi_params.mi_stride >> 1) + | 
 |       ((mi_col + mi_pos.col) >> 1); | 
 |   if (prev_frame_mvs->mfmv0.as_int == INVALID_MV) return 0; | 
 |  | 
 |   MV_REFERENCE_FRAME rf[2]; | 
 |   av1_set_ref_frame(rf, ref_frame); | 
 |  | 
 |   const uint16_t weight_unit = 1;  // mi_size_wide[BLOCK_8X8]; | 
 |   const int cur_frame_index = cm->cur_frame->order_hint; | 
 |   const RefCntBuffer *const buf_0 = get_ref_frame_buf(cm, rf[0]); | 
 |   const int frame0_index = buf_0->order_hint; | 
 |   const int cur_offset_0 = get_relative_dist(&cm->seq_params->order_hint_info, | 
 |                                              cur_frame_index, frame0_index); | 
 |   int idx; | 
 |   const int allow_high_precision_mv = cm->features.allow_high_precision_mv; | 
 |   const int force_integer_mv = cm->features.cur_frame_force_integer_mv; | 
 |  | 
 |   int_mv this_refmv; | 
 |   av1_get_mv_projection(&this_refmv.as_mv, prev_frame_mvs->mfmv0.as_mv, | 
 |                         cur_offset_0, prev_frame_mvs->ref_frame_offset); | 
 |   lower_mv_precision(&this_refmv.as_mv, allow_high_precision_mv, | 
 |                      force_integer_mv); | 
 |  | 
 |   if (rf[1] == NONE_FRAME) { | 
 |     if (blk_row == 0 && blk_col == 0) { | 
 |       if (abs(this_refmv.as_mv.row - gm_mv_candidates[0].as_mv.row) >= 16 || | 
 |           abs(this_refmv.as_mv.col - gm_mv_candidates[0].as_mv.col) >= 16) | 
 |         mode_context[ref_frame] |= (1 << GLOBALMV_OFFSET); | 
 |     } | 
 |  | 
 |     for (idx = 0; idx < *refmv_count; ++idx) | 
 |       if (this_refmv.as_int == ref_mv_stack[idx].this_mv.as_int) break; | 
 |  | 
 |     if (idx < *refmv_count) ref_mv_weight[idx] += 2 * weight_unit; | 
 |  | 
 |     if (idx == *refmv_count && *refmv_count < MAX_REF_MV_STACK_SIZE) { | 
 |       ref_mv_stack[idx].this_mv.as_int = this_refmv.as_int; | 
 |       ref_mv_weight[idx] = 2 * weight_unit; | 
 |       ++(*refmv_count); | 
 |     } | 
 |   } else { | 
 |     // Process compound inter mode | 
 |     const RefCntBuffer *const buf_1 = get_ref_frame_buf(cm, rf[1]); | 
 |     const int frame1_index = buf_1->order_hint; | 
 |     const int cur_offset_1 = get_relative_dist(&cm->seq_params->order_hint_info, | 
 |                                                cur_frame_index, frame1_index); | 
 |     int_mv comp_refmv; | 
 |     av1_get_mv_projection(&comp_refmv.as_mv, prev_frame_mvs->mfmv0.as_mv, | 
 |                           cur_offset_1, prev_frame_mvs->ref_frame_offset); | 
 |     lower_mv_precision(&comp_refmv.as_mv, allow_high_precision_mv, | 
 |                        force_integer_mv); | 
 |  | 
 |     if (blk_row == 0 && blk_col == 0) { | 
 |       if (abs(this_refmv.as_mv.row - gm_mv_candidates[0].as_mv.row) >= 16 || | 
 |           abs(this_refmv.as_mv.col - gm_mv_candidates[0].as_mv.col) >= 16 || | 
 |           abs(comp_refmv.as_mv.row - gm_mv_candidates[1].as_mv.row) >= 16 || | 
 |           abs(comp_refmv.as_mv.col - gm_mv_candidates[1].as_mv.col) >= 16) | 
 |         mode_context[ref_frame] |= (1 << GLOBALMV_OFFSET); | 
 |     } | 
 |  | 
 |     for (idx = 0; idx < *refmv_count; ++idx) { | 
 |       if (this_refmv.as_int == ref_mv_stack[idx].this_mv.as_int && | 
 |           comp_refmv.as_int == ref_mv_stack[idx].comp_mv.as_int) | 
 |         break; | 
 |     } | 
 |  | 
 |     if (idx < *refmv_count) ref_mv_weight[idx] += 2 * weight_unit; | 
 |  | 
 |     if (idx == *refmv_count && *refmv_count < MAX_REF_MV_STACK_SIZE) { | 
 |       ref_mv_stack[idx].this_mv.as_int = this_refmv.as_int; | 
 |       ref_mv_stack[idx].comp_mv.as_int = comp_refmv.as_int; | 
 |       ref_mv_weight[idx] = 2 * weight_unit; | 
 |       ++(*refmv_count); | 
 |     } | 
 |   } | 
 |  | 
 |   return 1; | 
 | } | 
 |  | 
 | static inline void process_compound_ref_mv_candidate( | 
 |     const MB_MODE_INFO *const candidate, const AV1_COMMON *const cm, | 
 |     const MV_REFERENCE_FRAME *const rf, int_mv ref_id[2][2], | 
 |     int ref_id_count[2], int_mv ref_diff[2][2], int ref_diff_count[2]) { | 
 |   for (int rf_idx = 0; rf_idx < 2; ++rf_idx) { | 
 |     MV_REFERENCE_FRAME can_rf = candidate->ref_frame[rf_idx]; | 
 |  | 
 |     for (int cmp_idx = 0; cmp_idx < 2; ++cmp_idx) { | 
 |       if (can_rf == rf[cmp_idx] && ref_id_count[cmp_idx] < 2) { | 
 |         ref_id[cmp_idx][ref_id_count[cmp_idx]] = candidate->mv[rf_idx]; | 
 |         ++ref_id_count[cmp_idx]; | 
 |       } else if (can_rf > INTRA_FRAME && ref_diff_count[cmp_idx] < 2) { | 
 |         int_mv this_mv = candidate->mv[rf_idx]; | 
 |         if (cm->ref_frame_sign_bias[can_rf] != | 
 |             cm->ref_frame_sign_bias[rf[cmp_idx]]) { | 
 |           this_mv.as_mv.row = -this_mv.as_mv.row; | 
 |           this_mv.as_mv.col = -this_mv.as_mv.col; | 
 |         } | 
 |         ref_diff[cmp_idx][ref_diff_count[cmp_idx]] = this_mv; | 
 |         ++ref_diff_count[cmp_idx]; | 
 |       } | 
 |     } | 
 |   } | 
 | } | 
 |  | 
 | static inline void process_single_ref_mv_candidate( | 
 |     const MB_MODE_INFO *const candidate, const AV1_COMMON *const cm, | 
 |     MV_REFERENCE_FRAME ref_frame, uint8_t *const refmv_count, | 
 |     CANDIDATE_MV ref_mv_stack[MAX_REF_MV_STACK_SIZE], | 
 |     uint16_t ref_mv_weight[MAX_REF_MV_STACK_SIZE]) { | 
 |   for (int rf_idx = 0; rf_idx < 2; ++rf_idx) { | 
 |     if (candidate->ref_frame[rf_idx] > INTRA_FRAME) { | 
 |       int_mv this_mv = candidate->mv[rf_idx]; | 
 |       if (cm->ref_frame_sign_bias[candidate->ref_frame[rf_idx]] != | 
 |           cm->ref_frame_sign_bias[ref_frame]) { | 
 |         this_mv.as_mv.row = -this_mv.as_mv.row; | 
 |         this_mv.as_mv.col = -this_mv.as_mv.col; | 
 |       } | 
 |       int stack_idx; | 
 |       for (stack_idx = 0; stack_idx < *refmv_count; ++stack_idx) { | 
 |         const int_mv stack_mv = ref_mv_stack[stack_idx].this_mv; | 
 |         if (this_mv.as_int == stack_mv.as_int) break; | 
 |       } | 
 |  | 
 |       if (stack_idx == *refmv_count) { | 
 |         ref_mv_stack[stack_idx].this_mv = this_mv; | 
 |  | 
 |         // TODO(jingning): Set an arbitrary small number here. The weight | 
 |         // doesn't matter as long as it is properly initialized. | 
 |         ref_mv_weight[stack_idx] = 2; | 
 |         ++(*refmv_count); | 
 |       } | 
 |     } | 
 |   } | 
 | } | 
 |  | 
 | static inline void setup_ref_mv_list( | 
 |     const AV1_COMMON *cm, const MACROBLOCKD *xd, MV_REFERENCE_FRAME ref_frame, | 
 |     uint8_t *const refmv_count, | 
 |     CANDIDATE_MV ref_mv_stack[MAX_REF_MV_STACK_SIZE], | 
 |     uint16_t ref_mv_weight[MAX_REF_MV_STACK_SIZE], | 
 |     int_mv mv_ref_list[MAX_MV_REF_CANDIDATES], int_mv *gm_mv_candidates, | 
 |     int mi_row, int mi_col, int16_t *mode_context) { | 
 |   const int bs = AOMMAX(xd->width, xd->height); | 
 |   const int has_tr = has_top_right(cm, xd, mi_row, mi_col, bs); | 
 |   MV_REFERENCE_FRAME rf[2]; | 
 |  | 
 |   const TileInfo *const tile = &xd->tile; | 
 |   int max_row_offset = 0, max_col_offset = 0; | 
 |   const int row_adj = (xd->height < mi_size_high[BLOCK_8X8]) && (mi_row & 0x01); | 
 |   const int col_adj = (xd->width < mi_size_wide[BLOCK_8X8]) && (mi_col & 0x01); | 
 |   int processed_rows = 0; | 
 |   int processed_cols = 0; | 
 |  | 
 |   av1_set_ref_frame(rf, ref_frame); | 
 |   mode_context[ref_frame] = 0; | 
 |   *refmv_count = 0; | 
 |  | 
 |   // Find valid maximum row/col offset. | 
 |   if (xd->up_available) { | 
 |     max_row_offset = -(MVREF_ROW_COLS << 1) + row_adj; | 
 |  | 
 |     if (xd->height < mi_size_high[BLOCK_8X8]) | 
 |       max_row_offset = -(2 << 1) + row_adj; | 
 |  | 
 |     max_row_offset = find_valid_row_offset(tile, mi_row, max_row_offset); | 
 |   } | 
 |  | 
 |   if (xd->left_available) { | 
 |     max_col_offset = -(MVREF_ROW_COLS << 1) + col_adj; | 
 |  | 
 |     if (xd->width < mi_size_wide[BLOCK_8X8]) | 
 |       max_col_offset = -(2 << 1) + col_adj; | 
 |  | 
 |     max_col_offset = find_valid_col_offset(tile, mi_col, max_col_offset); | 
 |   } | 
 |  | 
 |   uint8_t col_match_count = 0; | 
 |   uint8_t row_match_count = 0; | 
 |   uint8_t newmv_count = 0; | 
 |  | 
 |   // Scan the first above row mode info. row_offset = -1; | 
 |   if (abs(max_row_offset) >= 1) | 
 |     scan_row_mbmi(cm, xd, mi_col, rf, -1, ref_mv_stack, ref_mv_weight, | 
 |                   refmv_count, &row_match_count, &newmv_count, gm_mv_candidates, | 
 |                   max_row_offset, &processed_rows); | 
 |   // Scan the first left column mode info. col_offset = -1; | 
 |   if (abs(max_col_offset) >= 1) | 
 |     scan_col_mbmi(cm, xd, mi_row, rf, -1, ref_mv_stack, ref_mv_weight, | 
 |                   refmv_count, &col_match_count, &newmv_count, gm_mv_candidates, | 
 |                   max_col_offset, &processed_cols); | 
 |   // Check top-right boundary | 
 |   if (has_tr) | 
 |     scan_blk_mbmi(cm, xd, mi_row, mi_col, rf, -1, xd->width, ref_mv_stack, | 
 |                   ref_mv_weight, &row_match_count, &newmv_count, | 
 |                   gm_mv_candidates, refmv_count); | 
 |  | 
 |   const uint8_t nearest_match = (row_match_count > 0) + (col_match_count > 0); | 
 |   const uint8_t nearest_refmv_count = *refmv_count; | 
 |  | 
 |   // TODO(yunqing): for comp_search, do it for all 3 cases. | 
 |   for (int idx = 0; idx < nearest_refmv_count; ++idx) | 
 |     ref_mv_weight[idx] += REF_CAT_LEVEL; | 
 |  | 
 |   if (cm->features.allow_ref_frame_mvs) { | 
 |     int is_available = 0; | 
 |     const int voffset = AOMMAX(mi_size_high[BLOCK_8X8], xd->height); | 
 |     const int hoffset = AOMMAX(mi_size_wide[BLOCK_8X8], xd->width); | 
 |     const int blk_row_end = AOMMIN(xd->height, mi_size_high[BLOCK_64X64]); | 
 |     const int blk_col_end = AOMMIN(xd->width, mi_size_wide[BLOCK_64X64]); | 
 |  | 
 |     const int tpl_sample_pos[3][2] = { | 
 |       { voffset, -2 }, | 
 |       { voffset, hoffset }, | 
 |       { voffset - 2, hoffset }, | 
 |     }; | 
 |     const int allow_extension = (xd->height >= mi_size_high[BLOCK_8X8]) && | 
 |                                 (xd->height < mi_size_high[BLOCK_64X64]) && | 
 |                                 (xd->width >= mi_size_wide[BLOCK_8X8]) && | 
 |                                 (xd->width < mi_size_wide[BLOCK_64X64]); | 
 |  | 
 |     const int step_h = (xd->height >= mi_size_high[BLOCK_64X64]) | 
 |                            ? mi_size_high[BLOCK_16X16] | 
 |                            : mi_size_high[BLOCK_8X8]; | 
 |     const int step_w = (xd->width >= mi_size_wide[BLOCK_64X64]) | 
 |                            ? mi_size_wide[BLOCK_16X16] | 
 |                            : mi_size_wide[BLOCK_8X8]; | 
 |  | 
 |     for (int blk_row = 0; blk_row < blk_row_end; blk_row += step_h) { | 
 |       for (int blk_col = 0; blk_col < blk_col_end; blk_col += step_w) { | 
 |         int ret = add_tpl_ref_mv(cm, xd, mi_row, mi_col, ref_frame, blk_row, | 
 |                                  blk_col, gm_mv_candidates, refmv_count, | 
 |                                  ref_mv_stack, ref_mv_weight, mode_context); | 
 |         if (blk_row == 0 && blk_col == 0) is_available = ret; | 
 |       } | 
 |     } | 
 |  | 
 |     if (is_available == 0) mode_context[ref_frame] |= (1 << GLOBALMV_OFFSET); | 
 |  | 
 |     for (int i = 0; i < 3 && allow_extension; ++i) { | 
 |       const int blk_row = tpl_sample_pos[i][0]; | 
 |       const int blk_col = tpl_sample_pos[i][1]; | 
 |  | 
 |       if (!check_sb_border(mi_row, mi_col, blk_row, blk_col)) continue; | 
 |       add_tpl_ref_mv(cm, xd, mi_row, mi_col, ref_frame, blk_row, blk_col, | 
 |                      gm_mv_candidates, refmv_count, ref_mv_stack, ref_mv_weight, | 
 |                      mode_context); | 
 |     } | 
 |   } | 
 |  | 
 |   uint8_t dummy_newmv_count = 0; | 
 |  | 
 |   // Scan the second outer area. | 
 |   scan_blk_mbmi(cm, xd, mi_row, mi_col, rf, -1, -1, ref_mv_stack, ref_mv_weight, | 
 |                 &row_match_count, &dummy_newmv_count, gm_mv_candidates, | 
 |                 refmv_count); | 
 |  | 
 |   for (int idx = 2; idx <= MVREF_ROW_COLS; ++idx) { | 
 |     const int row_offset = -(idx << 1) + 1 + row_adj; | 
 |     const int col_offset = -(idx << 1) + 1 + col_adj; | 
 |  | 
 |     if (abs(row_offset) <= abs(max_row_offset) && | 
 |         abs(row_offset) > processed_rows) | 
 |       scan_row_mbmi(cm, xd, mi_col, rf, row_offset, ref_mv_stack, ref_mv_weight, | 
 |                     refmv_count, &row_match_count, &dummy_newmv_count, | 
 |                     gm_mv_candidates, max_row_offset, &processed_rows); | 
 |  | 
 |     if (abs(col_offset) <= abs(max_col_offset) && | 
 |         abs(col_offset) > processed_cols) | 
 |       scan_col_mbmi(cm, xd, mi_row, rf, col_offset, ref_mv_stack, ref_mv_weight, | 
 |                     refmv_count, &col_match_count, &dummy_newmv_count, | 
 |                     gm_mv_candidates, max_col_offset, &processed_cols); | 
 |   } | 
 |  | 
 |   const uint8_t ref_match_count = (row_match_count > 0) + (col_match_count > 0); | 
 |  | 
 |   switch (nearest_match) { | 
 |     case 0: | 
 |       if (ref_match_count >= 1) mode_context[ref_frame] |= 1; | 
 |       if (ref_match_count == 1) | 
 |         mode_context[ref_frame] |= (1 << REFMV_OFFSET); | 
 |       else if (ref_match_count >= 2) | 
 |         mode_context[ref_frame] |= (2 << REFMV_OFFSET); | 
 |       break; | 
 |     case 1: | 
 |       mode_context[ref_frame] |= (newmv_count > 0) ? 2 : 3; | 
 |       if (ref_match_count == 1) | 
 |         mode_context[ref_frame] |= (3 << REFMV_OFFSET); | 
 |       else if (ref_match_count >= 2) | 
 |         mode_context[ref_frame] |= (4 << REFMV_OFFSET); | 
 |       break; | 
 |     case 2: | 
 |     default: | 
 |       if (newmv_count >= 1) | 
 |         mode_context[ref_frame] |= 4; | 
 |       else | 
 |         mode_context[ref_frame] |= 5; | 
 |  | 
 |       mode_context[ref_frame] |= (5 << REFMV_OFFSET); | 
 |       break; | 
 |   } | 
 |  | 
 |   // Rank the likelihood and assign nearest and near mvs. | 
 |   int len = nearest_refmv_count; | 
 |   while (len > 0) { | 
 |     int nr_len = 0; | 
 |     for (int idx = 1; idx < len; ++idx) { | 
 |       if (ref_mv_weight[idx - 1] < ref_mv_weight[idx]) { | 
 |         const CANDIDATE_MV tmp_mv = ref_mv_stack[idx - 1]; | 
 |         const uint16_t tmp_ref_mv_weight = ref_mv_weight[idx - 1]; | 
 |         ref_mv_stack[idx - 1] = ref_mv_stack[idx]; | 
 |         ref_mv_stack[idx] = tmp_mv; | 
 |         ref_mv_weight[idx - 1] = ref_mv_weight[idx]; | 
 |         ref_mv_weight[idx] = tmp_ref_mv_weight; | 
 |         nr_len = idx; | 
 |       } | 
 |     } | 
 |     len = nr_len; | 
 |   } | 
 |  | 
 |   len = *refmv_count; | 
 |   while (len > nearest_refmv_count) { | 
 |     int nr_len = nearest_refmv_count; | 
 |     for (int idx = nearest_refmv_count + 1; idx < len; ++idx) { | 
 |       if (ref_mv_weight[idx - 1] < ref_mv_weight[idx]) { | 
 |         const CANDIDATE_MV tmp_mv = ref_mv_stack[idx - 1]; | 
 |         const uint16_t tmp_ref_mv_weight = ref_mv_weight[idx - 1]; | 
 |         ref_mv_stack[idx - 1] = ref_mv_stack[idx]; | 
 |         ref_mv_stack[idx] = tmp_mv; | 
 |         ref_mv_weight[idx - 1] = ref_mv_weight[idx]; | 
 |         ref_mv_weight[idx] = tmp_ref_mv_weight; | 
 |         nr_len = idx; | 
 |       } | 
 |     } | 
 |     len = nr_len; | 
 |   } | 
 |  | 
 |   int mi_width = AOMMIN(mi_size_wide[BLOCK_64X64], xd->width); | 
 |   mi_width = AOMMIN(mi_width, cm->mi_params.mi_cols - mi_col); | 
 |   int mi_height = AOMMIN(mi_size_high[BLOCK_64X64], xd->height); | 
 |   mi_height = AOMMIN(mi_height, cm->mi_params.mi_rows - mi_row); | 
 |   const int mi_size = AOMMIN(mi_width, mi_height); | 
 |   if (rf[1] > NONE_FRAME) { | 
 |     // TODO(jingning, yunqing): Refactor and consolidate the compound and | 
 |     // single reference frame modes. Reduce unnecessary redundancy. | 
 |     if (*refmv_count < MAX_MV_REF_CANDIDATES) { | 
 |       int_mv ref_id[2][2], ref_diff[2][2]; | 
 |       int ref_id_count[2] = { 0 }, ref_diff_count[2] = { 0 }; | 
 |  | 
 |       for (int idx = 0; abs(max_row_offset) >= 1 && idx < mi_size;) { | 
 |         const MB_MODE_INFO *const candidate = xd->mi[-xd->mi_stride + idx]; | 
 |         process_compound_ref_mv_candidate( | 
 |             candidate, cm, rf, ref_id, ref_id_count, ref_diff, ref_diff_count); | 
 |         idx += mi_size_wide[candidate->bsize]; | 
 |       } | 
 |  | 
 |       for (int idx = 0; abs(max_col_offset) >= 1 && idx < mi_size;) { | 
 |         const MB_MODE_INFO *const candidate = xd->mi[idx * xd->mi_stride - 1]; | 
 |         process_compound_ref_mv_candidate( | 
 |             candidate, cm, rf, ref_id, ref_id_count, ref_diff, ref_diff_count); | 
 |         idx += mi_size_high[candidate->bsize]; | 
 |       } | 
 |  | 
 |       // Build up the compound mv predictor | 
 |       int_mv comp_list[MAX_MV_REF_CANDIDATES][2]; | 
 |  | 
 |       for (int idx = 0; idx < 2; ++idx) { | 
 |         int comp_idx = 0; | 
 |         for (int list_idx = 0; | 
 |              list_idx < ref_id_count[idx] && comp_idx < MAX_MV_REF_CANDIDATES; | 
 |              ++list_idx, ++comp_idx) | 
 |           comp_list[comp_idx][idx] = ref_id[idx][list_idx]; | 
 |         for (int list_idx = 0; | 
 |              list_idx < ref_diff_count[idx] && comp_idx < MAX_MV_REF_CANDIDATES; | 
 |              ++list_idx, ++comp_idx) | 
 |           comp_list[comp_idx][idx] = ref_diff[idx][list_idx]; | 
 |         for (; comp_idx < MAX_MV_REF_CANDIDATES; ++comp_idx) | 
 |           comp_list[comp_idx][idx] = gm_mv_candidates[idx]; | 
 |       } | 
 |  | 
 |       if (*refmv_count) { | 
 |         assert(*refmv_count == 1); | 
 |         if (comp_list[0][0].as_int == ref_mv_stack[0].this_mv.as_int && | 
 |             comp_list[0][1].as_int == ref_mv_stack[0].comp_mv.as_int) { | 
 |           ref_mv_stack[*refmv_count].this_mv = comp_list[1][0]; | 
 |           ref_mv_stack[*refmv_count].comp_mv = comp_list[1][1]; | 
 |         } else { | 
 |           ref_mv_stack[*refmv_count].this_mv = comp_list[0][0]; | 
 |           ref_mv_stack[*refmv_count].comp_mv = comp_list[0][1]; | 
 |         } | 
 |         ref_mv_weight[*refmv_count] = 2; | 
 |         ++*refmv_count; | 
 |       } else { | 
 |         for (int idx = 0; idx < MAX_MV_REF_CANDIDATES; ++idx) { | 
 |           ref_mv_stack[*refmv_count].this_mv = comp_list[idx][0]; | 
 |           ref_mv_stack[*refmv_count].comp_mv = comp_list[idx][1]; | 
 |           ref_mv_weight[*refmv_count] = 2; | 
 |           ++*refmv_count; | 
 |         } | 
 |       } | 
 |     } | 
 |  | 
 |     assert(*refmv_count >= 2); | 
 |  | 
 |     for (int idx = 0; idx < *refmv_count; ++idx) { | 
 |       clamp_mv_ref(&ref_mv_stack[idx].this_mv.as_mv, xd->width << MI_SIZE_LOG2, | 
 |                    xd->height << MI_SIZE_LOG2, xd); | 
 |       clamp_mv_ref(&ref_mv_stack[idx].comp_mv.as_mv, xd->width << MI_SIZE_LOG2, | 
 |                    xd->height << MI_SIZE_LOG2, xd); | 
 |     } | 
 |   } else { | 
 |     // Handle single reference frame extension | 
 |     for (int idx = 0; abs(max_row_offset) >= 1 && idx < mi_size && | 
 |                       *refmv_count < MAX_MV_REF_CANDIDATES;) { | 
 |       const MB_MODE_INFO *const candidate = xd->mi[-xd->mi_stride + idx]; | 
 |       process_single_ref_mv_candidate(candidate, cm, ref_frame, refmv_count, | 
 |                                       ref_mv_stack, ref_mv_weight); | 
 |       idx += mi_size_wide[candidate->bsize]; | 
 |     } | 
 |  | 
 |     for (int idx = 0; abs(max_col_offset) >= 1 && idx < mi_size && | 
 |                       *refmv_count < MAX_MV_REF_CANDIDATES;) { | 
 |       const MB_MODE_INFO *const candidate = xd->mi[idx * xd->mi_stride - 1]; | 
 |       process_single_ref_mv_candidate(candidate, cm, ref_frame, refmv_count, | 
 |                                       ref_mv_stack, ref_mv_weight); | 
 |       idx += mi_size_high[candidate->bsize]; | 
 |     } | 
 |  | 
 |     for (int idx = 0; idx < *refmv_count; ++idx) { | 
 |       clamp_mv_ref(&ref_mv_stack[idx].this_mv.as_mv, xd->width << MI_SIZE_LOG2, | 
 |                    xd->height << MI_SIZE_LOG2, xd); | 
 |     } | 
 |  | 
 |     if (mv_ref_list != NULL) { | 
 |       for (int idx = *refmv_count; idx < MAX_MV_REF_CANDIDATES; ++idx) | 
 |         mv_ref_list[idx].as_int = gm_mv_candidates[0].as_int; | 
 |  | 
 |       for (int idx = 0; idx < AOMMIN(MAX_MV_REF_CANDIDATES, *refmv_count); | 
 |            ++idx) { | 
 |         mv_ref_list[idx].as_int = ref_mv_stack[idx].this_mv.as_int; | 
 |       } | 
 |     } | 
 |   } | 
 | } | 
 |  | 
 | void av1_find_mv_refs(const AV1_COMMON *cm, const MACROBLOCKD *xd, | 
 |                       MB_MODE_INFO *mi, MV_REFERENCE_FRAME ref_frame, | 
 |                       uint8_t ref_mv_count[MODE_CTX_REF_FRAMES], | 
 |                       CANDIDATE_MV ref_mv_stack[][MAX_REF_MV_STACK_SIZE], | 
 |                       uint16_t ref_mv_weight[][MAX_REF_MV_STACK_SIZE], | 
 |                       int_mv mv_ref_list[][MAX_MV_REF_CANDIDATES], | 
 |                       int_mv *global_mvs, int16_t *mode_context) { | 
 |   const int mi_row = xd->mi_row; | 
 |   const int mi_col = xd->mi_col; | 
 |   int_mv gm_mv[2]; | 
 |  | 
 |   if (ref_frame == INTRA_FRAME) { | 
 |     gm_mv[0].as_int = gm_mv[1].as_int = 0; | 
 |     if (global_mvs != NULL) { | 
 |       global_mvs[ref_frame].as_int = INVALID_MV; | 
 |     } | 
 |   } else { | 
 |     const BLOCK_SIZE bsize = mi->bsize; | 
 |     const int allow_high_precision_mv = cm->features.allow_high_precision_mv; | 
 |     const int force_integer_mv = cm->features.cur_frame_force_integer_mv; | 
 |     if (ref_frame < REF_FRAMES) { | 
 |       gm_mv[0] = gm_get_motion_vector(&cm->global_motion[ref_frame], | 
 |                                       allow_high_precision_mv, bsize, mi_col, | 
 |                                       mi_row, force_integer_mv); | 
 |       gm_mv[1].as_int = 0; | 
 |       if (global_mvs != NULL) global_mvs[ref_frame] = gm_mv[0]; | 
 |     } else { | 
 |       MV_REFERENCE_FRAME rf[2]; | 
 |       av1_set_ref_frame(rf, ref_frame); | 
 |       gm_mv[0] = gm_get_motion_vector(&cm->global_motion[rf[0]], | 
 |                                       allow_high_precision_mv, bsize, mi_col, | 
 |                                       mi_row, force_integer_mv); | 
 |       gm_mv[1] = gm_get_motion_vector(&cm->global_motion[rf[1]], | 
 |                                       allow_high_precision_mv, bsize, mi_col, | 
 |                                       mi_row, force_integer_mv); | 
 |     } | 
 |   } | 
 |  | 
 |   setup_ref_mv_list(cm, xd, ref_frame, &ref_mv_count[ref_frame], | 
 |                     ref_mv_stack[ref_frame], ref_mv_weight[ref_frame], | 
 |                     mv_ref_list ? mv_ref_list[ref_frame] : NULL, gm_mv, mi_row, | 
 |                     mi_col, mode_context); | 
 | } | 
 |  | 
 | void av1_find_best_ref_mvs(int allow_hp, int_mv *mvlist, int_mv *nearest_mv, | 
 |                            int_mv *near_mv, int is_integer) { | 
 |   int i; | 
 |   // Make sure all the candidates are properly clamped etc | 
 |   for (i = 0; i < MAX_MV_REF_CANDIDATES; ++i) { | 
 |     lower_mv_precision(&mvlist[i].as_mv, allow_hp, is_integer); | 
 |   } | 
 |   *nearest_mv = mvlist[0]; | 
 |   *near_mv = mvlist[1]; | 
 | } | 
 |  | 
 | void av1_setup_frame_buf_refs(AV1_COMMON *cm) { | 
 |   cm->cur_frame->order_hint = cm->current_frame.order_hint; | 
 |   cm->cur_frame->display_order_hint = cm->current_frame.display_order_hint; | 
 |   cm->cur_frame->pyramid_level = cm->current_frame.pyramid_level; | 
 |   cm->cur_frame->filter_level[0] = -1; | 
 |   cm->cur_frame->filter_level[1] = -1; | 
 |   MV_REFERENCE_FRAME ref_frame; | 
 |   for (ref_frame = LAST_FRAME; ref_frame <= ALTREF_FRAME; ++ref_frame) { | 
 |     const RefCntBuffer *const buf = get_ref_frame_buf(cm, ref_frame); | 
 |     if (buf != NULL) { | 
 |       cm->cur_frame->ref_order_hints[ref_frame - LAST_FRAME] = buf->order_hint; | 
 |       cm->cur_frame->ref_display_order_hint[ref_frame - LAST_FRAME] = | 
 |           buf->display_order_hint; | 
 |     } | 
 |   } | 
 | } | 
 |  | 
 | void av1_setup_frame_sign_bias(AV1_COMMON *cm) { | 
 |   MV_REFERENCE_FRAME ref_frame; | 
 |   for (ref_frame = LAST_FRAME; ref_frame <= ALTREF_FRAME; ++ref_frame) { | 
 |     const RefCntBuffer *const buf = get_ref_frame_buf(cm, ref_frame); | 
 |     if (cm->seq_params->order_hint_info.enable_order_hint && buf != NULL) { | 
 |       const int ref_order_hint = buf->order_hint; | 
 |       cm->ref_frame_sign_bias[ref_frame] = | 
 |           (get_relative_dist(&cm->seq_params->order_hint_info, ref_order_hint, | 
 |                              (int)cm->current_frame.order_hint) <= 0) | 
 |               ? 0 | 
 |               : 1; | 
 |     } else { | 
 |       cm->ref_frame_sign_bias[ref_frame] = 0; | 
 |     } | 
 |   } | 
 | } | 
 |  | 
 | #define MAX_OFFSET_WIDTH 64 | 
 | #define MAX_OFFSET_HEIGHT 0 | 
 |  | 
 | static int get_block_position(AV1_COMMON *cm, int *mi_r, int *mi_c, int blk_row, | 
 |                               int blk_col, MV mv, int sign_bias) { | 
 |   const int base_blk_row = (blk_row >> 3) << 3; | 
 |   const int base_blk_col = (blk_col >> 3) << 3; | 
 |  | 
 |   const int row_offset = (mv.row >= 0) ? (mv.row >> (4 + MI_SIZE_LOG2)) | 
 |                                        : -((-mv.row) >> (4 + MI_SIZE_LOG2)); | 
 |  | 
 |   const int col_offset = (mv.col >= 0) ? (mv.col >> (4 + MI_SIZE_LOG2)) | 
 |                                        : -((-mv.col) >> (4 + MI_SIZE_LOG2)); | 
 |  | 
 |   const int row = | 
 |       (sign_bias == 1) ? blk_row - row_offset : blk_row + row_offset; | 
 |   const int col = | 
 |       (sign_bias == 1) ? blk_col - col_offset : blk_col + col_offset; | 
 |  | 
 |   if (row < 0 || row >= (cm->mi_params.mi_rows >> 1) || col < 0 || | 
 |       col >= (cm->mi_params.mi_cols >> 1)) | 
 |     return 0; | 
 |  | 
 |   if (row < base_blk_row - (MAX_OFFSET_HEIGHT >> 3) || | 
 |       row >= base_blk_row + 8 + (MAX_OFFSET_HEIGHT >> 3) || | 
 |       col < base_blk_col - (MAX_OFFSET_WIDTH >> 3) || | 
 |       col >= base_blk_col + 8 + (MAX_OFFSET_WIDTH >> 3)) | 
 |     return 0; | 
 |  | 
 |   *mi_r = row; | 
 |   *mi_c = col; | 
 |  | 
 |   return 1; | 
 | } | 
 |  | 
 | // Note: motion_filed_projection finds motion vectors of current frame's | 
 | // reference frame, and projects them to current frame. To make it clear, | 
 | // let's call current frame's reference frame as start frame. | 
 | // Call Start frame's reference frames as reference frames. | 
 | // Call ref_offset as frame distances between start frame and its reference | 
 | // frames. | 
 | static int motion_field_projection(AV1_COMMON *cm, | 
 |                                    MV_REFERENCE_FRAME start_frame, int dir) { | 
 |   TPL_MV_REF *tpl_mvs_base = cm->tpl_mvs; | 
 |   int ref_offset[REF_FRAMES] = { 0 }; | 
 |  | 
 |   const RefCntBuffer *const start_frame_buf = | 
 |       get_ref_frame_buf(cm, start_frame); | 
 |   if (start_frame_buf == NULL) return 0; | 
 |  | 
 |   if (start_frame_buf->frame_type == KEY_FRAME || | 
 |       start_frame_buf->frame_type == INTRA_ONLY_FRAME) | 
 |     return 0; | 
 |  | 
 |   if (start_frame_buf->mi_rows != cm->mi_params.mi_rows || | 
 |       start_frame_buf->mi_cols != cm->mi_params.mi_cols) | 
 |     return 0; | 
 |  | 
 |   const int start_frame_order_hint = start_frame_buf->order_hint; | 
 |   const unsigned int *const ref_order_hints = | 
 |       &start_frame_buf->ref_order_hints[0]; | 
 |   const int cur_order_hint = cm->cur_frame->order_hint; | 
 |   int start_to_current_frame_offset = get_relative_dist( | 
 |       &cm->seq_params->order_hint_info, start_frame_order_hint, cur_order_hint); | 
 |  | 
 |   for (MV_REFERENCE_FRAME rf = LAST_FRAME; rf <= INTER_REFS_PER_FRAME; ++rf) { | 
 |     ref_offset[rf] = get_relative_dist(&cm->seq_params->order_hint_info, | 
 |                                        start_frame_order_hint, | 
 |                                        ref_order_hints[rf - LAST_FRAME]); | 
 |   } | 
 |  | 
 |   if (dir == 2) start_to_current_frame_offset = -start_to_current_frame_offset; | 
 |  | 
 |   MV_REF *mv_ref_base = start_frame_buf->mvs; | 
 |   const int mvs_rows = (cm->mi_params.mi_rows + 1) >> 1; | 
 |   const int mvs_cols = (cm->mi_params.mi_cols + 1) >> 1; | 
 |  | 
 |   for (int blk_row = 0; blk_row < mvs_rows; ++blk_row) { | 
 |     for (int blk_col = 0; blk_col < mvs_cols; ++blk_col) { | 
 |       MV_REF *mv_ref = &mv_ref_base[blk_row * mvs_cols + blk_col]; | 
 |       MV fwd_mv = mv_ref->mv.as_mv; | 
 |  | 
 |       if (mv_ref->ref_frame > INTRA_FRAME) { | 
 |         int_mv this_mv; | 
 |         int mi_r, mi_c; | 
 |         const int ref_frame_offset = ref_offset[mv_ref->ref_frame]; | 
 |  | 
 |         int pos_valid = | 
 |             abs(ref_frame_offset) <= MAX_FRAME_DISTANCE && | 
 |             ref_frame_offset > 0 && | 
 |             abs(start_to_current_frame_offset) <= MAX_FRAME_DISTANCE; | 
 |  | 
 |         if (pos_valid) { | 
 |           av1_get_mv_projection(&this_mv.as_mv, fwd_mv, | 
 |                                 start_to_current_frame_offset, | 
 |                                 ref_frame_offset); | 
 |           pos_valid = get_block_position(cm, &mi_r, &mi_c, blk_row, blk_col, | 
 |                                          this_mv.as_mv, dir >> 1); | 
 |         } | 
 |  | 
 |         if (pos_valid) { | 
 |           const int mi_offset = mi_r * (cm->mi_params.mi_stride >> 1) + mi_c; | 
 |  | 
 |           tpl_mvs_base[mi_offset].mfmv0.as_mv.row = fwd_mv.row; | 
 |           tpl_mvs_base[mi_offset].mfmv0.as_mv.col = fwd_mv.col; | 
 |           tpl_mvs_base[mi_offset].ref_frame_offset = ref_frame_offset; | 
 |         } | 
 |       } | 
 |     } | 
 |   } | 
 |  | 
 |   return 1; | 
 | } | 
 |  | 
 | // cm->ref_frame_side is calculated here, and will be used in | 
 | // av1_copy_frame_mvs() to affect how mvs are copied. | 
 | void av1_calculate_ref_frame_side(AV1_COMMON *cm) { | 
 |   const OrderHintInfo *const order_hint_info = &cm->seq_params->order_hint_info; | 
 |  | 
 |   memset(cm->ref_frame_side, 0, sizeof(cm->ref_frame_side)); | 
 |   if (!order_hint_info->enable_order_hint) return; | 
 |  | 
 |   const int cur_order_hint = cm->cur_frame->order_hint; | 
 |  | 
 |   for (int ref_frame = LAST_FRAME; ref_frame <= ALTREF_FRAME; ref_frame++) { | 
 |     const RefCntBuffer *const buf = get_ref_frame_buf(cm, ref_frame); | 
 |     int order_hint = 0; | 
 |  | 
 |     if (buf != NULL) order_hint = buf->order_hint; | 
 |  | 
 |     if (get_relative_dist(order_hint_info, order_hint, cur_order_hint) > 0) | 
 |       cm->ref_frame_side[ref_frame] = 1; | 
 |     else if (order_hint == cur_order_hint) | 
 |       cm->ref_frame_side[ref_frame] = -1; | 
 |   } | 
 | } | 
 |  | 
 | void av1_setup_motion_field(AV1_COMMON *cm) { | 
 |   const OrderHintInfo *const order_hint_info = &cm->seq_params->order_hint_info; | 
 |  | 
 |   if (!order_hint_info->enable_order_hint) return; | 
 |  | 
 |   TPL_MV_REF *tpl_mvs_base = cm->tpl_mvs; | 
 |   int size = ((cm->mi_params.mi_rows + MAX_MIB_SIZE) >> 1) * | 
 |              (cm->mi_params.mi_stride >> 1); | 
 |   for (int idx = 0; idx < size; ++idx) { | 
 |     tpl_mvs_base[idx].mfmv0.as_int = INVALID_MV; | 
 |     tpl_mvs_base[idx].ref_frame_offset = 0; | 
 |   } | 
 |  | 
 |   const int cur_order_hint = cm->cur_frame->order_hint; | 
 |   const RefCntBuffer *ref_buf[INTER_REFS_PER_FRAME]; | 
 |   int ref_order_hint[INTER_REFS_PER_FRAME]; | 
 |  | 
 |   for (int ref_frame = LAST_FRAME; ref_frame <= ALTREF_FRAME; ref_frame++) { | 
 |     const int ref_idx = ref_frame - LAST_FRAME; | 
 |     const RefCntBuffer *const buf = get_ref_frame_buf(cm, ref_frame); | 
 |     int order_hint = 0; | 
 |  | 
 |     if (buf != NULL) order_hint = buf->order_hint; | 
 |  | 
 |     ref_buf[ref_idx] = buf; | 
 |     ref_order_hint[ref_idx] = order_hint; | 
 |   } | 
 |  | 
 |   int ref_stamp = MFMV_STACK_SIZE - 1; | 
 |  | 
 |   if (ref_buf[LAST_FRAME - LAST_FRAME] != NULL) { | 
 |     const int alt_of_lst_order_hint = | 
 |         ref_buf[LAST_FRAME - LAST_FRAME] | 
 |             ->ref_order_hints[ALTREF_FRAME - LAST_FRAME]; | 
 |  | 
 |     const int is_lst_overlay = | 
 |         (alt_of_lst_order_hint == ref_order_hint[GOLDEN_FRAME - LAST_FRAME]); | 
 |     if (!is_lst_overlay) motion_field_projection(cm, LAST_FRAME, 2); | 
 |     --ref_stamp; | 
 |   } | 
 |  | 
 |   if (get_relative_dist(order_hint_info, | 
 |                         ref_order_hint[BWDREF_FRAME - LAST_FRAME], | 
 |                         cur_order_hint) > 0) { | 
 |     if (motion_field_projection(cm, BWDREF_FRAME, 0)) --ref_stamp; | 
 |   } | 
 |  | 
 |   if (get_relative_dist(order_hint_info, | 
 |                         ref_order_hint[ALTREF2_FRAME - LAST_FRAME], | 
 |                         cur_order_hint) > 0) { | 
 |     if (motion_field_projection(cm, ALTREF2_FRAME, 0)) --ref_stamp; | 
 |   } | 
 |  | 
 |   if (get_relative_dist(order_hint_info, | 
 |                         ref_order_hint[ALTREF_FRAME - LAST_FRAME], | 
 |                         cur_order_hint) > 0 && | 
 |       ref_stamp >= 0) | 
 |     if (motion_field_projection(cm, ALTREF_FRAME, 0)) --ref_stamp; | 
 |  | 
 |   if (ref_stamp >= 0) motion_field_projection(cm, LAST2_FRAME, 2); | 
 | } | 
 |  | 
 | static inline void record_samples(const MB_MODE_INFO *mbmi, int *pts, | 
 |                                   int *pts_inref, int row_offset, int sign_r, | 
 |                                   int col_offset, int sign_c) { | 
 |   const int bw = block_size_wide[mbmi->bsize]; | 
 |   const int bh = block_size_high[mbmi->bsize]; | 
 |   const int x = col_offset * MI_SIZE + sign_c * bw / 2 - 1; | 
 |   const int y = row_offset * MI_SIZE + sign_r * bh / 2 - 1; | 
 |  | 
 |   pts[0] = GET_MV_SUBPEL(x); | 
 |   pts[1] = GET_MV_SUBPEL(y); | 
 |   pts_inref[0] = pts[0] + mbmi->mv[0].as_mv.col; | 
 |   pts_inref[1] = pts[1] + mbmi->mv[0].as_mv.row; | 
 | } | 
 |  | 
 | // Select samples according to the motion vector difference. | 
 | uint8_t av1_selectSamples(MV *mv, int *pts, int *pts_inref, int len, | 
 |                           BLOCK_SIZE bsize) { | 
 |   const int bw = block_size_wide[bsize]; | 
 |   const int bh = block_size_high[bsize]; | 
 |   const int thresh = clamp(AOMMAX(bw, bh), 16, 112); | 
 |   uint8_t ret = 0; | 
 |   assert(len <= LEAST_SQUARES_SAMPLES_MAX); | 
 |  | 
 |   // Only keep the samples with MV differences within threshold. | 
 |   for (int i = 0; i < len; ++i) { | 
 |     const int diff = abs(pts_inref[2 * i] - pts[2 * i] - mv->col) + | 
 |                      abs(pts_inref[2 * i + 1] - pts[2 * i + 1] - mv->row); | 
 |     if (diff > thresh) continue; | 
 |     if (ret != i) { | 
 |       memcpy(pts + 2 * ret, pts + 2 * i, 2 * sizeof(pts[0])); | 
 |       memcpy(pts_inref + 2 * ret, pts_inref + 2 * i, 2 * sizeof(pts_inref[0])); | 
 |     } | 
 |     ++ret; | 
 |   } | 
 |   // Keep at least 1 sample. | 
 |   return AOMMAX(ret, 1); | 
 | } | 
 |  | 
 | // Note: Samples returned are at 1/8-pel precision | 
 | // Sample are the neighbor block center point's coordinates relative to the | 
 | // left-top pixel of current block. | 
 | uint8_t av1_findSamples(const AV1_COMMON *cm, MACROBLOCKD *xd, int *pts, | 
 |                         int *pts_inref) { | 
 |   const MB_MODE_INFO *const mbmi0 = xd->mi[0]; | 
 |   const int ref_frame = mbmi0->ref_frame[0]; | 
 |   const int up_available = xd->up_available; | 
 |   const int left_available = xd->left_available; | 
 |   uint8_t np = 0; | 
 |   int do_tl = 1; | 
 |   int do_tr = 1; | 
 |   const int mi_stride = xd->mi_stride; | 
 |   const int mi_row = xd->mi_row; | 
 |   const int mi_col = xd->mi_col; | 
 |  | 
 |   // scan the nearest above rows | 
 |   if (up_available) { | 
 |     const int mi_row_offset = -1; | 
 |     const MB_MODE_INFO *mbmi = xd->mi[mi_row_offset * mi_stride]; | 
 |     uint8_t superblock_width = mi_size_wide[mbmi->bsize]; | 
 |  | 
 |     if (xd->width <= superblock_width) { | 
 |       // Handle "current block width <= above block width" case. | 
 |       const int col_offset = -mi_col % superblock_width; | 
 |  | 
 |       if (col_offset < 0) do_tl = 0; | 
 |       if (col_offset + superblock_width > xd->width) do_tr = 0; | 
 |  | 
 |       if (mbmi->ref_frame[0] == ref_frame && mbmi->ref_frame[1] == NONE_FRAME) { | 
 |         record_samples(mbmi, pts, pts_inref, 0, -1, col_offset, 1); | 
 |         pts += 2; | 
 |         pts_inref += 2; | 
 |         if (++np >= LEAST_SQUARES_SAMPLES_MAX) return LEAST_SQUARES_SAMPLES_MAX; | 
 |       } | 
 |     } else { | 
 |       // Handle "current block width > above block width" case. | 
 |       for (int i = 0; i < AOMMIN(xd->width, cm->mi_params.mi_cols - mi_col); | 
 |            i += superblock_width) { | 
 |         mbmi = xd->mi[i + mi_row_offset * mi_stride]; | 
 |         superblock_width = mi_size_wide[mbmi->bsize]; | 
 |  | 
 |         if (mbmi->ref_frame[0] == ref_frame && | 
 |             mbmi->ref_frame[1] == NONE_FRAME) { | 
 |           record_samples(mbmi, pts, pts_inref, 0, -1, i, 1); | 
 |           pts += 2; | 
 |           pts_inref += 2; | 
 |           if (++np >= LEAST_SQUARES_SAMPLES_MAX) | 
 |             return LEAST_SQUARES_SAMPLES_MAX; | 
 |         } | 
 |       } | 
 |     } | 
 |   } | 
 |   assert(np <= LEAST_SQUARES_SAMPLES_MAX); | 
 |  | 
 |   // scan the nearest left columns | 
 |   if (left_available) { | 
 |     const int mi_col_offset = -1; | 
 |     const MB_MODE_INFO *mbmi = xd->mi[mi_col_offset]; | 
 |     uint8_t superblock_height = mi_size_high[mbmi->bsize]; | 
 |  | 
 |     if (xd->height <= superblock_height) { | 
 |       // Handle "current block height <= above block height" case. | 
 |       const int row_offset = -mi_row % superblock_height; | 
 |  | 
 |       if (row_offset < 0) do_tl = 0; | 
 |  | 
 |       if (mbmi->ref_frame[0] == ref_frame && mbmi->ref_frame[1] == NONE_FRAME) { | 
 |         record_samples(mbmi, pts, pts_inref, row_offset, 1, 0, -1); | 
 |         pts += 2; | 
 |         pts_inref += 2; | 
 |         np++; | 
 |         if (np >= LEAST_SQUARES_SAMPLES_MAX) return LEAST_SQUARES_SAMPLES_MAX; | 
 |       } | 
 |     } else { | 
 |       // Handle "current block height > above block height" case. | 
 |       for (int i = 0; i < AOMMIN(xd->height, cm->mi_params.mi_rows - mi_row); | 
 |            i += superblock_height) { | 
 |         mbmi = xd->mi[mi_col_offset + i * mi_stride]; | 
 |         superblock_height = mi_size_high[mbmi->bsize]; | 
 |  | 
 |         if (mbmi->ref_frame[0] == ref_frame && | 
 |             mbmi->ref_frame[1] == NONE_FRAME) { | 
 |           record_samples(mbmi, pts, pts_inref, i, 1, 0, -1); | 
 |           pts += 2; | 
 |           pts_inref += 2; | 
 |           if (++np >= LEAST_SQUARES_SAMPLES_MAX) | 
 |             return LEAST_SQUARES_SAMPLES_MAX; | 
 |         } | 
 |       } | 
 |     } | 
 |   } | 
 |   assert(np <= LEAST_SQUARES_SAMPLES_MAX); | 
 |  | 
 |   // Top-left block | 
 |   if (do_tl && left_available && up_available) { | 
 |     const int mi_row_offset = -1; | 
 |     const int mi_col_offset = -1; | 
 |     MB_MODE_INFO *mbmi = xd->mi[mi_col_offset + mi_row_offset * mi_stride]; | 
 |  | 
 |     if (mbmi->ref_frame[0] == ref_frame && mbmi->ref_frame[1] == NONE_FRAME) { | 
 |       record_samples(mbmi, pts, pts_inref, 0, -1, 0, -1); | 
 |       pts += 2; | 
 |       pts_inref += 2; | 
 |       if (++np >= LEAST_SQUARES_SAMPLES_MAX) return LEAST_SQUARES_SAMPLES_MAX; | 
 |     } | 
 |   } | 
 |   assert(np <= LEAST_SQUARES_SAMPLES_MAX); | 
 |  | 
 |   // Top-right block | 
 |   if (do_tr && | 
 |       has_top_right(cm, xd, mi_row, mi_col, AOMMAX(xd->width, xd->height))) { | 
 |     const POSITION trb_pos = { -1, xd->width }; | 
 |     const TileInfo *const tile = &xd->tile; | 
 |     if (is_inside(tile, mi_col, mi_row, &trb_pos)) { | 
 |       const int mi_row_offset = -1; | 
 |       const int mi_col_offset = xd->width; | 
 |       const MB_MODE_INFO *mbmi = | 
 |           xd->mi[mi_col_offset + mi_row_offset * mi_stride]; | 
 |  | 
 |       if (mbmi->ref_frame[0] == ref_frame && mbmi->ref_frame[1] == NONE_FRAME) { | 
 |         record_samples(mbmi, pts, pts_inref, 0, -1, xd->width, 1); | 
 |         if (++np >= LEAST_SQUARES_SAMPLES_MAX) return LEAST_SQUARES_SAMPLES_MAX; | 
 |       } | 
 |     } | 
 |   } | 
 |   assert(np <= LEAST_SQUARES_SAMPLES_MAX); | 
 |  | 
 |   return np; | 
 | } | 
 |  | 
 | void av1_setup_skip_mode_allowed(AV1_COMMON *cm) { | 
 |   const OrderHintInfo *const order_hint_info = &cm->seq_params->order_hint_info; | 
 |   SkipModeInfo *const skip_mode_info = &cm->current_frame.skip_mode_info; | 
 |  | 
 |   skip_mode_info->skip_mode_allowed = 0; | 
 |   skip_mode_info->ref_frame_idx_0 = INVALID_IDX; | 
 |   skip_mode_info->ref_frame_idx_1 = INVALID_IDX; | 
 |  | 
 |   if (!order_hint_info->enable_order_hint || frame_is_intra_only(cm) || | 
 |       cm->current_frame.reference_mode == SINGLE_REFERENCE) | 
 |     return; | 
 |  | 
 |   const int cur_order_hint = cm->current_frame.order_hint; | 
 |   int ref_order_hints[2] = { -1, INT_MAX }; | 
 |   int ref_idx[2] = { INVALID_IDX, INVALID_IDX }; | 
 |  | 
 |   // Identify the nearest forward and backward references. | 
 |   for (int i = 0; i < INTER_REFS_PER_FRAME; ++i) { | 
 |     const RefCntBuffer *const buf = get_ref_frame_buf(cm, LAST_FRAME + i); | 
 |     if (buf == NULL) continue; | 
 |  | 
 |     const int ref_order_hint = buf->order_hint; | 
 |     if (get_relative_dist(order_hint_info, ref_order_hint, cur_order_hint) < | 
 |         0) { | 
 |       // Forward reference | 
 |       if (ref_order_hints[0] == -1 || | 
 |           get_relative_dist(order_hint_info, ref_order_hint, | 
 |                             ref_order_hints[0]) > 0) { | 
 |         ref_order_hints[0] = ref_order_hint; | 
 |         ref_idx[0] = i; | 
 |       } | 
 |     } else if (get_relative_dist(order_hint_info, ref_order_hint, | 
 |                                  cur_order_hint) > 0) { | 
 |       // Backward reference | 
 |       if (ref_order_hints[1] == INT_MAX || | 
 |           get_relative_dist(order_hint_info, ref_order_hint, | 
 |                             ref_order_hints[1]) < 0) { | 
 |         ref_order_hints[1] = ref_order_hint; | 
 |         ref_idx[1] = i; | 
 |       } | 
 |     } | 
 |   } | 
 |  | 
 |   if (ref_idx[0] != INVALID_IDX && ref_idx[1] != INVALID_IDX) { | 
 |     // == Bi-directional prediction == | 
 |     skip_mode_info->skip_mode_allowed = 1; | 
 |     skip_mode_info->ref_frame_idx_0 = AOMMIN(ref_idx[0], ref_idx[1]); | 
 |     skip_mode_info->ref_frame_idx_1 = AOMMAX(ref_idx[0], ref_idx[1]); | 
 |   } else if (ref_idx[0] != INVALID_IDX && ref_idx[1] == INVALID_IDX) { | 
 |     // == Forward prediction only == | 
 |     // Identify the second nearest forward reference. | 
 |     ref_order_hints[1] = -1; | 
 |     for (int i = 0; i < INTER_REFS_PER_FRAME; ++i) { | 
 |       const RefCntBuffer *const buf = get_ref_frame_buf(cm, LAST_FRAME + i); | 
 |       if (buf == NULL) continue; | 
 |  | 
 |       const int ref_order_hint = buf->order_hint; | 
 |       if ((ref_order_hints[0] != -1 && | 
 |            get_relative_dist(order_hint_info, ref_order_hint, | 
 |                              ref_order_hints[0]) < 0) && | 
 |           (ref_order_hints[1] == -1 || | 
 |            get_relative_dist(order_hint_info, ref_order_hint, | 
 |                              ref_order_hints[1]) > 0)) { | 
 |         // Second closest forward reference | 
 |         ref_order_hints[1] = ref_order_hint; | 
 |         ref_idx[1] = i; | 
 |       } | 
 |     } | 
 |     if (ref_order_hints[1] != -1) { | 
 |       skip_mode_info->skip_mode_allowed = 1; | 
 |       skip_mode_info->ref_frame_idx_0 = AOMMIN(ref_idx[0], ref_idx[1]); | 
 |       skip_mode_info->ref_frame_idx_1 = AOMMAX(ref_idx[0], ref_idx[1]); | 
 |     } | 
 |   } | 
 | } | 
 |  | 
 | typedef struct { | 
 |   int map_idx;        // frame map index | 
 |   RefCntBuffer *buf;  // frame buffer | 
 |   int sort_idx;       // index based on the offset to be used for sorting | 
 | } REF_FRAME_INFO; | 
 |  | 
 | // Compares the sort_idx fields. If they are equal, then compares the map_idx | 
 | // fields to break the tie. This ensures a stable sort. | 
 | static int compare_ref_frame_info(const void *arg_a, const void *arg_b) { | 
 |   const REF_FRAME_INFO *info_a = (REF_FRAME_INFO *)arg_a; | 
 |   const REF_FRAME_INFO *info_b = (REF_FRAME_INFO *)arg_b; | 
 |  | 
 |   const int sort_idx_diff = info_a->sort_idx - info_b->sort_idx; | 
 |   if (sort_idx_diff != 0) return sort_idx_diff; | 
 |   return info_a->map_idx - info_b->map_idx; | 
 | } | 
 |  | 
 | static inline void set_ref_frame_info(int *remapped_ref_idx, int frame_idx, | 
 |                                       REF_FRAME_INFO *ref_info) { | 
 |   assert(frame_idx >= 0 && frame_idx < INTER_REFS_PER_FRAME); | 
 |  | 
 |   remapped_ref_idx[frame_idx] = ref_info->map_idx; | 
 | } | 
 |  | 
 | void av1_set_frame_refs(AV1_COMMON *const cm, int *remapped_ref_idx, | 
 |                         int lst_map_idx, int gld_map_idx) { | 
 |   int lst_frame_sort_idx = -1; | 
 |   int gld_frame_sort_idx = -1; | 
 |  | 
 |   assert(cm->seq_params->order_hint_info.enable_order_hint); | 
 |   assert(cm->seq_params->order_hint_info.order_hint_bits_minus_1 >= 0); | 
 |   const int cur_order_hint = (int)cm->current_frame.order_hint; | 
 |   const int cur_frame_sort_idx = | 
 |       1 << cm->seq_params->order_hint_info.order_hint_bits_minus_1; | 
 |  | 
 |   REF_FRAME_INFO ref_frame_info[REF_FRAMES]; | 
 |   int ref_flag_list[INTER_REFS_PER_FRAME] = { 0, 0, 0, 0, 0, 0, 0 }; | 
 |  | 
 |   for (int i = 0; i < REF_FRAMES; ++i) { | 
 |     const int map_idx = i; | 
 |  | 
 |     ref_frame_info[i].map_idx = map_idx; | 
 |     ref_frame_info[i].sort_idx = -1; | 
 |  | 
 |     RefCntBuffer *const buf = cm->ref_frame_map[map_idx]; | 
 |     ref_frame_info[i].buf = buf; | 
 |  | 
 |     if (buf == NULL) continue; | 
 |     // If this assertion fails, there is a reference leak. | 
 |     assert(buf->ref_count > 0); | 
 |  | 
 |     const int offset = (int)buf->order_hint; | 
 |     ref_frame_info[i].sort_idx = | 
 |         (offset == -1) ? -1 | 
 |                        : cur_frame_sort_idx + | 
 |                              get_relative_dist(&cm->seq_params->order_hint_info, | 
 |                                                offset, cur_order_hint); | 
 |     assert(ref_frame_info[i].sort_idx >= -1); | 
 |  | 
 |     if (map_idx == lst_map_idx) lst_frame_sort_idx = ref_frame_info[i].sort_idx; | 
 |     if (map_idx == gld_map_idx) gld_frame_sort_idx = ref_frame_info[i].sort_idx; | 
 |   } | 
 |  | 
 |   // Confirm both LAST_FRAME and GOLDEN_FRAME are valid forward reference | 
 |   // frames. | 
 |   if (lst_frame_sort_idx == -1 || lst_frame_sort_idx >= cur_frame_sort_idx) { | 
 |     aom_internal_error(cm->error, AOM_CODEC_CORRUPT_FRAME, | 
 |                        "Inter frame requests a look-ahead frame as LAST"); | 
 |   } | 
 |   if (gld_frame_sort_idx == -1 || gld_frame_sort_idx >= cur_frame_sort_idx) { | 
 |     aom_internal_error(cm->error, AOM_CODEC_CORRUPT_FRAME, | 
 |                        "Inter frame requests a look-ahead frame as GOLDEN"); | 
 |   } | 
 |  | 
 |   // Sort ref frames based on their frame_offset values. | 
 |   qsort(ref_frame_info, REF_FRAMES, sizeof(REF_FRAME_INFO), | 
 |         compare_ref_frame_info); | 
 |  | 
 |   // Identify forward and backward reference frames. | 
 |   // Forward  reference: offset < order_hint | 
 |   // Backward reference: offset >= order_hint | 
 |   int fwd_start_idx = 0, fwd_end_idx = REF_FRAMES - 1; | 
 |  | 
 |   for (int i = 0; i < REF_FRAMES; i++) { | 
 |     if (ref_frame_info[i].sort_idx == -1) { | 
 |       fwd_start_idx++; | 
 |       continue; | 
 |     } | 
 |  | 
 |     if (ref_frame_info[i].sort_idx >= cur_frame_sort_idx) { | 
 |       fwd_end_idx = i - 1; | 
 |       break; | 
 |     } | 
 |   } | 
 |  | 
 |   int bwd_start_idx = fwd_end_idx + 1; | 
 |   int bwd_end_idx = REF_FRAMES - 1; | 
 |  | 
 |   // === Backward Reference Frames === | 
 |  | 
 |   // == ALTREF_FRAME == | 
 |   if (bwd_start_idx <= bwd_end_idx) { | 
 |     set_ref_frame_info(remapped_ref_idx, ALTREF_FRAME - LAST_FRAME, | 
 |                        &ref_frame_info[bwd_end_idx]); | 
 |     ref_flag_list[ALTREF_FRAME - LAST_FRAME] = 1; | 
 |     bwd_end_idx--; | 
 |   } | 
 |  | 
 |   // == BWDREF_FRAME == | 
 |   if (bwd_start_idx <= bwd_end_idx) { | 
 |     set_ref_frame_info(remapped_ref_idx, BWDREF_FRAME - LAST_FRAME, | 
 |                        &ref_frame_info[bwd_start_idx]); | 
 |     ref_flag_list[BWDREF_FRAME - LAST_FRAME] = 1; | 
 |     bwd_start_idx++; | 
 |   } | 
 |  | 
 |   // == ALTREF2_FRAME == | 
 |   if (bwd_start_idx <= bwd_end_idx) { | 
 |     set_ref_frame_info(remapped_ref_idx, ALTREF2_FRAME - LAST_FRAME, | 
 |                        &ref_frame_info[bwd_start_idx]); | 
 |     ref_flag_list[ALTREF2_FRAME - LAST_FRAME] = 1; | 
 |   } | 
 |  | 
 |   // === Forward Reference Frames === | 
 |  | 
 |   for (int i = fwd_start_idx; i <= fwd_end_idx; ++i) { | 
 |     // == LAST_FRAME == | 
 |     if (ref_frame_info[i].map_idx == lst_map_idx) { | 
 |       set_ref_frame_info(remapped_ref_idx, LAST_FRAME - LAST_FRAME, | 
 |                          &ref_frame_info[i]); | 
 |       ref_flag_list[LAST_FRAME - LAST_FRAME] = 1; | 
 |     } | 
 |  | 
 |     // == GOLDEN_FRAME == | 
 |     if (ref_frame_info[i].map_idx == gld_map_idx) { | 
 |       set_ref_frame_info(remapped_ref_idx, GOLDEN_FRAME - LAST_FRAME, | 
 |                          &ref_frame_info[i]); | 
 |       ref_flag_list[GOLDEN_FRAME - LAST_FRAME] = 1; | 
 |     } | 
 |   } | 
 |  | 
 |   assert(ref_flag_list[LAST_FRAME - LAST_FRAME] == 1 && | 
 |          ref_flag_list[GOLDEN_FRAME - LAST_FRAME] == 1); | 
 |  | 
 |   // == LAST2_FRAME == | 
 |   // == LAST3_FRAME == | 
 |   // == BWDREF_FRAME == | 
 |   // == ALTREF2_FRAME == | 
 |   // == ALTREF_FRAME == | 
 |  | 
 |   // Set up the reference frames in the anti-chronological order. | 
 |   static const MV_REFERENCE_FRAME ref_frame_list[INTER_REFS_PER_FRAME - 2] = { | 
 |     LAST2_FRAME, LAST3_FRAME, BWDREF_FRAME, ALTREF2_FRAME, ALTREF_FRAME | 
 |   }; | 
 |  | 
 |   int ref_idx; | 
 |   for (ref_idx = 0; ref_idx < (INTER_REFS_PER_FRAME - 2); ref_idx++) { | 
 |     const MV_REFERENCE_FRAME ref_frame = ref_frame_list[ref_idx]; | 
 |  | 
 |     if (ref_flag_list[ref_frame - LAST_FRAME] == 1) continue; | 
 |  | 
 |     while (fwd_start_idx <= fwd_end_idx && | 
 |            (ref_frame_info[fwd_end_idx].map_idx == lst_map_idx || | 
 |             ref_frame_info[fwd_end_idx].map_idx == gld_map_idx)) { | 
 |       fwd_end_idx--; | 
 |     } | 
 |     if (fwd_start_idx > fwd_end_idx) break; | 
 |  | 
 |     set_ref_frame_info(remapped_ref_idx, ref_frame - LAST_FRAME, | 
 |                        &ref_frame_info[fwd_end_idx]); | 
 |     ref_flag_list[ref_frame - LAST_FRAME] = 1; | 
 |  | 
 |     fwd_end_idx--; | 
 |   } | 
 |  | 
 |   // Assign all the remaining frame(s), if any, to the earliest reference | 
 |   // frame. | 
 |   for (; ref_idx < (INTER_REFS_PER_FRAME - 2); ref_idx++) { | 
 |     const MV_REFERENCE_FRAME ref_frame = ref_frame_list[ref_idx]; | 
 |     if (ref_flag_list[ref_frame - LAST_FRAME] == 1) continue; | 
 |     set_ref_frame_info(remapped_ref_idx, ref_frame - LAST_FRAME, | 
 |                        &ref_frame_info[fwd_start_idx]); | 
 |     ref_flag_list[ref_frame - LAST_FRAME] = 1; | 
 |   } | 
 |  | 
 |   for (int i = 0; i < INTER_REFS_PER_FRAME; i++) { | 
 |     assert(ref_flag_list[i] == 1); | 
 |   } | 
 | } |