|  | /* | 
|  | *  Copyright (c) 2011 The WebM project authors. All Rights Reserved. | 
|  | * | 
|  | *  Use of this source code is governed by a BSD-style license | 
|  | *  that can be found in the LICENSE file in the root of the source | 
|  | *  tree. An additional intellectual property rights grant can be found | 
|  | *  in the file PATENTS.  All contributing project authors may | 
|  | *  be found in the AUTHORS file in the root of the source tree. | 
|  | */ | 
|  |  | 
|  | #include <assert.h> | 
|  |  | 
|  | #include "error_concealment.h" | 
|  | #include "onyxd_int.h" | 
|  | #include "decodemv.h" | 
|  | #include "vpx_mem/vpx_mem.h" | 
|  | #include "vp8/common/findnearmv.h" | 
|  |  | 
|  | #define MIN(x,y) (((x)<(y))?(x):(y)) | 
|  | #define MAX(x,y) (((x)>(y))?(x):(y)) | 
|  |  | 
|  | #define FLOOR(x,q) ((x) & -(1 << (q))) | 
|  |  | 
|  | #define NUM_NEIGHBORS 20 | 
|  |  | 
|  | typedef struct ec_position | 
|  | { | 
|  | int row; | 
|  | int col; | 
|  | } EC_POS; | 
|  |  | 
|  | /* | 
|  | * Regenerate the table in Matlab with: | 
|  | * x = meshgrid((1:4), (1:4)); | 
|  | * y = meshgrid((1:4), (1:4))'; | 
|  | * W = round((1./(sqrt(x.^2 + y.^2))*2^7)); | 
|  | * W(1,1) = 0; | 
|  | */ | 
|  | static const int weights_q7[5][5] = { | 
|  | {  0,   128,    64,    43,    32 }, | 
|  | {128,    91,    57,    40,    31 }, | 
|  | { 64,    57,    45,    36,    29 }, | 
|  | { 43,    40,    36,    30,    26 }, | 
|  | { 32,    31,    29,    26,    23 } | 
|  | }; | 
|  |  | 
|  | int vp8_alloc_overlap_lists(VP8D_COMP *pbi) | 
|  | { | 
|  | if (pbi->overlaps != NULL) | 
|  | { | 
|  | vpx_free(pbi->overlaps); | 
|  | pbi->overlaps = NULL; | 
|  | } | 
|  |  | 
|  | pbi->overlaps = vpx_calloc(pbi->common.mb_rows * pbi->common.mb_cols, | 
|  | sizeof(MB_OVERLAP)); | 
|  |  | 
|  | if (pbi->overlaps == NULL) | 
|  | return -1; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | void vp8_de_alloc_overlap_lists(VP8D_COMP *pbi) | 
|  | { | 
|  | vpx_free(pbi->overlaps); | 
|  | pbi->overlaps = NULL; | 
|  | } | 
|  |  | 
|  | /* Inserts a new overlap area value to the list of overlaps of a block */ | 
|  | static void assign_overlap(OVERLAP_NODE* overlaps, | 
|  | union b_mode_info *bmi, | 
|  | int overlap) | 
|  | { | 
|  | int i; | 
|  | if (overlap <= 0) | 
|  | return; | 
|  | /* Find and assign to the next empty overlap node in the list of overlaps. | 
|  | * Empty is defined as bmi == NULL */ | 
|  | for (i = 0; i < MAX_OVERLAPS; i++) | 
|  | { | 
|  | if (overlaps[i].bmi == NULL) | 
|  | { | 
|  | overlaps[i].bmi = bmi; | 
|  | overlaps[i].overlap = overlap; | 
|  | break; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | /* Calculates the overlap area between two 4x4 squares, where the first | 
|  | * square has its upper-left corner at (b1_row, b1_col) and the second | 
|  | * square has its upper-left corner at (b2_row, b2_col). Doesn't | 
|  | * properly handle squares which do not overlap. | 
|  | */ | 
|  | static int block_overlap(int b1_row, int b1_col, int b2_row, int b2_col) | 
|  | { | 
|  | const int int_top = MAX(b1_row, b2_row); // top | 
|  | const int int_left = MAX(b1_col, b2_col); // left | 
|  | /* Since each block is 4x4 pixels, adding 4 (Q3) to the left/top edge | 
|  | * gives us the right/bottom edge. | 
|  | */ | 
|  | const int int_right = MIN(b1_col + (4<<3), b2_col + (4<<3)); // right | 
|  | const int int_bottom = MIN(b1_row + (4<<3), b2_row + (4<<3)); // bottom | 
|  | return (int_bottom - int_top) * (int_right - int_left); | 
|  | } | 
|  |  | 
|  | /* Calculates the overlap area for all blocks in a macroblock at position | 
|  | * (mb_row, mb_col) in macroblocks, which are being overlapped by a given | 
|  | * overlapping block at position (new_row, new_col) (in pixels, Q3). The | 
|  | * first block being overlapped in the macroblock has position (first_blk_row, | 
|  | * first_blk_col) in blocks relative the upper-left corner of the image. | 
|  | */ | 
|  | static void calculate_overlaps_mb(B_OVERLAP *b_overlaps, union b_mode_info *bmi, | 
|  | int new_row, int new_col, | 
|  | int mb_row, int mb_col, | 
|  | int first_blk_row, int first_blk_col) | 
|  | { | 
|  | /* Find the blocks within this MB (defined by mb_row, mb_col) which are | 
|  | * overlapped by bmi and calculate and assign overlap for each of those | 
|  | * blocks. */ | 
|  |  | 
|  | /* Block coordinates relative the upper-left block */ | 
|  | const int rel_ol_blk_row = first_blk_row - mb_row * 4; | 
|  | const int rel_ol_blk_col = first_blk_col - mb_col * 4; | 
|  | /* If the block partly overlaps any previous MB, these coordinates | 
|  | * can be < 0. We don't want to access blocks in previous MBs. | 
|  | */ | 
|  | const int blk_idx = MAX(rel_ol_blk_row,0) * 4 + MAX(rel_ol_blk_col,0); | 
|  | /* Upper left overlapping block */ | 
|  | B_OVERLAP *b_ol_ul = &(b_overlaps[blk_idx]); | 
|  |  | 
|  | /* Calculate and assign overlaps for all blocks in this MB | 
|  | * which the motion compensated block overlaps | 
|  | */ | 
|  | /* Avoid calculating overlaps for blocks in later MBs */ | 
|  | int end_row = MIN(4 + mb_row * 4 - first_blk_row, 2); | 
|  | int end_col = MIN(4 + mb_col * 4 - first_blk_col, 2); | 
|  | int row, col; | 
|  |  | 
|  | /* Check if new_row and new_col are evenly divisible by 4 (Q3), | 
|  | * and if so we shouldn't check neighboring blocks | 
|  | */ | 
|  | if (new_row >= 0 && (new_row & 0x1F) == 0) | 
|  | end_row = 1; | 
|  | if (new_col >= 0 && (new_col & 0x1F) == 0) | 
|  | end_col = 1; | 
|  |  | 
|  | /* Check if the overlapping block partly overlaps a previous MB | 
|  | * and if so, we're overlapping fewer blocks in this MB. | 
|  | */ | 
|  | if (new_row < (mb_row*16)<<3) | 
|  | end_row = 1; | 
|  | if (new_col < (mb_col*16)<<3) | 
|  | end_col = 1; | 
|  |  | 
|  | for (row = 0; row < end_row; ++row) | 
|  | { | 
|  | for (col = 0; col < end_col; ++col) | 
|  | { | 
|  | /* input in Q3, result in Q6 */ | 
|  | const int overlap = block_overlap(new_row, new_col, | 
|  | (((first_blk_row + row) * | 
|  | 4) << 3), | 
|  | (((first_blk_col + col) * | 
|  | 4) << 3)); | 
|  | assign_overlap(b_ol_ul[row * 4 + col].overlaps, bmi, overlap); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | void vp8_calculate_overlaps(MB_OVERLAP *overlap_ul, | 
|  | int mb_rows, int mb_cols, | 
|  | union b_mode_info *bmi, | 
|  | int b_row, int b_col) | 
|  | { | 
|  | MB_OVERLAP *mb_overlap; | 
|  | int row, col, rel_row, rel_col; | 
|  | int new_row, new_col; | 
|  | int end_row, end_col; | 
|  | int overlap_b_row, overlap_b_col; | 
|  | int overlap_mb_row, overlap_mb_col; | 
|  |  | 
|  | /* mb subpixel position */ | 
|  | row = (4 * b_row) << 3; /* Q3 */ | 
|  | col = (4 * b_col) << 3; /* Q3 */ | 
|  |  | 
|  | /* reverse compensate for motion */ | 
|  | new_row = row - bmi->mv.as_mv.row; | 
|  | new_col = col - bmi->mv.as_mv.col; | 
|  |  | 
|  | if (new_row >= ((16*mb_rows) << 3) || new_col >= ((16*mb_cols) << 3)) | 
|  | { | 
|  | /* the new block ended up outside the frame */ | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (new_row <= (-4 << 3) || new_col <= (-4 << 3)) | 
|  | { | 
|  | /* outside the frame */ | 
|  | return; | 
|  | } | 
|  | /* overlapping block's position in blocks */ | 
|  | overlap_b_row = FLOOR(new_row / 4, 3) >> 3; | 
|  | overlap_b_col = FLOOR(new_col / 4, 3) >> 3; | 
|  |  | 
|  | /* overlapping block's MB position in MBs | 
|  | * operations are done in Q3 | 
|  | */ | 
|  | overlap_mb_row = FLOOR((overlap_b_row << 3) / 4, 3) >> 3; | 
|  | overlap_mb_col = FLOOR((overlap_b_col << 3) / 4, 3) >> 3; | 
|  |  | 
|  | end_row = MIN(mb_rows - overlap_mb_row, 2); | 
|  | end_col = MIN(mb_cols - overlap_mb_col, 2); | 
|  |  | 
|  | /* Don't calculate overlap for MBs we don't overlap */ | 
|  | /* Check if the new block row starts at the last block row of the MB */ | 
|  | if (abs(new_row - ((16*overlap_mb_row) << 3)) < ((3*4) << 3)) | 
|  | end_row = 1; | 
|  | /* Check if the new block col starts at the last block col of the MB */ | 
|  | if (abs(new_col - ((16*overlap_mb_col) << 3)) < ((3*4) << 3)) | 
|  | end_col = 1; | 
|  |  | 
|  | /* find the MB(s) this block is overlapping */ | 
|  | for (rel_row = 0; rel_row < end_row; ++rel_row) | 
|  | { | 
|  | for (rel_col = 0; rel_col < end_col; ++rel_col) | 
|  | { | 
|  | if (overlap_mb_row + rel_row < 0 || | 
|  | overlap_mb_col + rel_col < 0) | 
|  | continue; | 
|  | mb_overlap = overlap_ul + (overlap_mb_row + rel_row) * mb_cols + | 
|  | overlap_mb_col + rel_col; | 
|  |  | 
|  | calculate_overlaps_mb(mb_overlap->overlaps, bmi, | 
|  | new_row, new_col, | 
|  | overlap_mb_row + rel_row, | 
|  | overlap_mb_col + rel_col, | 
|  | overlap_b_row + rel_row, | 
|  | overlap_b_col + rel_col); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | /* Estimates a motion vector given the overlapping blocks' motion vectors. | 
|  | * Filters out all overlapping blocks which do not refer to the correct | 
|  | * reference frame type. | 
|  | */ | 
|  | static void estimate_mv(const OVERLAP_NODE *overlaps, union b_mode_info *bmi) | 
|  | { | 
|  | int i; | 
|  | int overlap_sum = 0; | 
|  | int row_acc = 0; | 
|  | int col_acc = 0; | 
|  |  | 
|  | bmi->mv.as_int = 0; | 
|  | for (i=0; i < MAX_OVERLAPS; ++i) | 
|  | { | 
|  | if (overlaps[i].bmi == NULL) | 
|  | break; | 
|  | col_acc += overlaps[i].overlap * overlaps[i].bmi->mv.as_mv.col; | 
|  | row_acc += overlaps[i].overlap * overlaps[i].bmi->mv.as_mv.row; | 
|  | overlap_sum += overlaps[i].overlap; | 
|  | } | 
|  | if (overlap_sum > 0) | 
|  | { | 
|  | /* Q9 / Q6 = Q3 */ | 
|  | bmi->mv.as_mv.col = col_acc / overlap_sum; | 
|  | bmi->mv.as_mv.row = row_acc / overlap_sum; | 
|  | } | 
|  | else | 
|  | { | 
|  | bmi->mv.as_mv.col = 0; | 
|  | bmi->mv.as_mv.row = 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | /* Estimates all motion vectors for a macroblock given the lists of | 
|  | * overlaps for each block. Decides whether or not the MVs must be clamped. | 
|  | */ | 
|  | static void estimate_mb_mvs(const B_OVERLAP *block_overlaps, | 
|  | MODE_INFO *mi, | 
|  | int mb_to_left_edge, | 
|  | int mb_to_right_edge, | 
|  | int mb_to_top_edge, | 
|  | int mb_to_bottom_edge) | 
|  | { | 
|  | int row, col; | 
|  | int non_zero_count = 0; | 
|  | MV * const filtered_mv = &(mi->mbmi.mv.as_mv); | 
|  | union b_mode_info * const bmi = mi->bmi; | 
|  | filtered_mv->col = 0; | 
|  | filtered_mv->row = 0; | 
|  | mi->mbmi.need_to_clamp_mvs = 0; | 
|  | for (row = 0; row < 4; ++row) | 
|  | { | 
|  | int this_b_to_top_edge = mb_to_top_edge + ((row*4)<<3); | 
|  | int this_b_to_bottom_edge = mb_to_bottom_edge - ((row*4)<<3); | 
|  | for (col = 0; col < 4; ++col) | 
|  | { | 
|  | int i = row * 4 + col; | 
|  | int this_b_to_left_edge = mb_to_left_edge + ((col*4)<<3); | 
|  | int this_b_to_right_edge = mb_to_right_edge - ((col*4)<<3); | 
|  | /* Estimate vectors for all blocks which are overlapped by this */ | 
|  | /* type. Interpolate/extrapolate the rest of the block's MVs */ | 
|  | estimate_mv(block_overlaps[i].overlaps, &(bmi[i])); | 
|  | mi->mbmi.need_to_clamp_mvs |= vp8_check_mv_bounds( | 
|  | &bmi[i].mv, | 
|  | this_b_to_left_edge, | 
|  | this_b_to_right_edge, | 
|  | this_b_to_top_edge, | 
|  | this_b_to_bottom_edge); | 
|  | if (bmi[i].mv.as_int != 0) | 
|  | { | 
|  | ++non_zero_count; | 
|  | filtered_mv->col += bmi[i].mv.as_mv.col; | 
|  | filtered_mv->row += bmi[i].mv.as_mv.row; | 
|  | } | 
|  | } | 
|  | } | 
|  | if (non_zero_count > 0) | 
|  | { | 
|  | filtered_mv->col /= non_zero_count; | 
|  | filtered_mv->row /= non_zero_count; | 
|  | } | 
|  | } | 
|  |  | 
|  | static void calc_prev_mb_overlaps(MB_OVERLAP *overlaps, MODE_INFO *prev_mi, | 
|  | int mb_row, int mb_col, | 
|  | int mb_rows, int mb_cols) | 
|  | { | 
|  | int sub_row; | 
|  | int sub_col; | 
|  | for (sub_row = 0; sub_row < 4; ++sub_row) | 
|  | { | 
|  | for (sub_col = 0; sub_col < 4; ++sub_col) | 
|  | { | 
|  | vp8_calculate_overlaps( | 
|  | overlaps, mb_rows, mb_cols, | 
|  | &(prev_mi->bmi[sub_row * 4 + sub_col]), | 
|  | 4 * mb_row + sub_row, | 
|  | 4 * mb_col + sub_col); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | /* Estimate all missing motion vectors. This function does the same as the one | 
|  | * above, but has different input arguments. */ | 
|  | static void estimate_missing_mvs(MB_OVERLAP *overlaps, | 
|  | MODE_INFO *mi, MODE_INFO *prev_mi, | 
|  | int mb_rows, int mb_cols, | 
|  | unsigned int first_corrupt) | 
|  | { | 
|  | int mb_row, mb_col; | 
|  | vpx_memset(overlaps, 0, sizeof(MB_OVERLAP) * mb_rows * mb_cols); | 
|  | /* First calculate the overlaps for all blocks */ | 
|  | for (mb_row = 0; mb_row < mb_rows; ++mb_row) | 
|  | { | 
|  | for (mb_col = 0; mb_col < mb_cols; ++mb_col) | 
|  | { | 
|  | /* We're only able to use blocks referring to the last frame | 
|  | * when extrapolating new vectors. | 
|  | */ | 
|  | if (prev_mi->mbmi.ref_frame == LAST_FRAME) | 
|  | { | 
|  | calc_prev_mb_overlaps(overlaps, prev_mi, | 
|  | mb_row, mb_col, | 
|  | mb_rows, mb_cols); | 
|  | } | 
|  | ++prev_mi; | 
|  | } | 
|  | ++prev_mi; | 
|  | } | 
|  |  | 
|  | mb_row = first_corrupt / mb_cols; | 
|  | mb_col = first_corrupt - mb_row * mb_cols; | 
|  | mi += mb_row*(mb_cols + 1) + mb_col; | 
|  | /* Go through all macroblocks in the current image with missing MVs | 
|  | * and calculate new MVs using the overlaps. | 
|  | */ | 
|  | for (; mb_row < mb_rows; ++mb_row) | 
|  | { | 
|  | int mb_to_top_edge = -((mb_row * 16)) << 3; | 
|  | int mb_to_bottom_edge = ((mb_rows - 1 - mb_row) * 16) << 3; | 
|  | for (; mb_col < mb_cols; ++mb_col) | 
|  | { | 
|  | int mb_to_left_edge = -((mb_col * 16) << 3); | 
|  | int mb_to_right_edge = ((mb_cols - 1 - mb_col) * 16) << 3; | 
|  | const B_OVERLAP *block_overlaps = | 
|  | overlaps[mb_row*mb_cols + mb_col].overlaps; | 
|  | mi->mbmi.ref_frame = LAST_FRAME; | 
|  | mi->mbmi.mode = SPLITMV; | 
|  | mi->mbmi.uv_mode = DC_PRED; | 
|  | mi->mbmi.partitioning = 3; | 
|  | mi->mbmi.segment_id = 0; | 
|  | estimate_mb_mvs(block_overlaps, | 
|  | mi, | 
|  | mb_to_left_edge, | 
|  | mb_to_right_edge, | 
|  | mb_to_top_edge, | 
|  | mb_to_bottom_edge); | 
|  | ++mi; | 
|  | } | 
|  | mb_col = 0; | 
|  | ++mi; | 
|  | } | 
|  | } | 
|  |  | 
|  | void vp8_estimate_missing_mvs(VP8D_COMP *pbi) | 
|  | { | 
|  | VP8_COMMON * const pc = &pbi->common; | 
|  | estimate_missing_mvs(pbi->overlaps, | 
|  | pc->mi, pc->prev_mi, | 
|  | pc->mb_rows, pc->mb_cols, | 
|  | pbi->mvs_corrupt_from_mb); | 
|  | } | 
|  |  | 
|  | static void assign_neighbor(EC_BLOCK *neighbor, MODE_INFO *mi, int block_idx) | 
|  | { | 
|  | assert(mi->mbmi.ref_frame < MAX_REF_FRAMES); | 
|  | neighbor->ref_frame = mi->mbmi.ref_frame; | 
|  | neighbor->mv = mi->bmi[block_idx].mv.as_mv; | 
|  | } | 
|  |  | 
|  | /* Finds the neighboring blocks of a macroblocks. In the general case | 
|  | * 20 blocks are found. If a fewer number of blocks are found due to | 
|  | * image boundaries, those positions in the EC_BLOCK array are left "empty". | 
|  | * The neighbors are enumerated with the upper-left neighbor as the first | 
|  | * element, the second element refers to the neighbor to right of the previous | 
|  | * neighbor, and so on. The last element refers to the neighbor below the first | 
|  | * neighbor. | 
|  | */ | 
|  | static void find_neighboring_blocks(MODE_INFO *mi, | 
|  | EC_BLOCK *neighbors, | 
|  | int mb_row, int mb_col, | 
|  | int mb_rows, int mb_cols, | 
|  | int mi_stride) | 
|  | { | 
|  | int i = 0; | 
|  | int j; | 
|  | if (mb_row > 0) | 
|  | { | 
|  | /* upper left */ | 
|  | if (mb_col > 0) | 
|  | assign_neighbor(&neighbors[i], mi - mi_stride - 1, 15); | 
|  | ++i; | 
|  | /* above */ | 
|  | for (j = 12; j < 16; ++j, ++i) | 
|  | assign_neighbor(&neighbors[i], mi - mi_stride, j); | 
|  | } | 
|  | else | 
|  | i += 5; | 
|  | if (mb_col < mb_cols - 1) | 
|  | { | 
|  | /* upper right */ | 
|  | if (mb_row > 0) | 
|  | assign_neighbor(&neighbors[i], mi - mi_stride + 1, 12); | 
|  | ++i; | 
|  | /* right */ | 
|  | for (j = 0; j <= 12; j += 4, ++i) | 
|  | assign_neighbor(&neighbors[i], mi + 1, j); | 
|  | } | 
|  | else | 
|  | i += 5; | 
|  | if (mb_row < mb_rows - 1) | 
|  | { | 
|  | /* lower right */ | 
|  | if (mb_col < mb_cols - 1) | 
|  | assign_neighbor(&neighbors[i], mi + mi_stride + 1, 0); | 
|  | ++i; | 
|  | /* below */ | 
|  | for (j = 0; j < 4; ++j, ++i) | 
|  | assign_neighbor(&neighbors[i], mi + mi_stride, j); | 
|  | } | 
|  | else | 
|  | i += 5; | 
|  | if (mb_col > 0) | 
|  | { | 
|  | /* lower left */ | 
|  | if (mb_row < mb_rows - 1) | 
|  | assign_neighbor(&neighbors[i], mi + mi_stride - 1, 4); | 
|  | ++i; | 
|  | /* left */ | 
|  | for (j = 3; j < 16; j += 4, ++i) | 
|  | { | 
|  | assign_neighbor(&neighbors[i], mi - 1, j); | 
|  | } | 
|  | } | 
|  | else | 
|  | i += 5; | 
|  | assert(i == 20); | 
|  | } | 
|  |  | 
|  | /* Interpolates all motion vectors for a macroblock from the neighboring blocks' | 
|  | * motion vectors. | 
|  | */ | 
|  | static void interpolate_mvs(MACROBLOCKD *mb, | 
|  | EC_BLOCK *neighbors, | 
|  | MV_REFERENCE_FRAME dom_ref_frame) | 
|  | { | 
|  | int row, col, i; | 
|  | MODE_INFO * const mi = mb->mode_info_context; | 
|  | /* Table with the position of the neighboring blocks relative the position | 
|  | * of the upper left block of the current MB. Starting with the upper left | 
|  | * neighbor and going to the right. | 
|  | */ | 
|  | const EC_POS neigh_pos[NUM_NEIGHBORS] = { | 
|  | {-1,-1}, {-1,0}, {-1,1}, {-1,2}, {-1,3}, | 
|  | {-1,4}, {0,4}, {1,4}, {2,4}, {3,4}, | 
|  | {4,4}, {4,3}, {4,2}, {4,1}, {4,0}, | 
|  | {4,-1}, {3,-1}, {2,-1}, {1,-1}, {0,-1} | 
|  | }; | 
|  | mi->mbmi.need_to_clamp_mvs = 0; | 
|  | for (row = 0; row < 4; ++row) | 
|  | { | 
|  | int mb_to_top_edge = mb->mb_to_top_edge + ((row*4)<<3); | 
|  | int mb_to_bottom_edge = mb->mb_to_bottom_edge - ((row*4)<<3); | 
|  | for (col = 0; col < 4; ++col) | 
|  | { | 
|  | int mb_to_left_edge = mb->mb_to_left_edge + ((col*4)<<3); | 
|  | int mb_to_right_edge = mb->mb_to_right_edge - ((col*4)<<3); | 
|  | int w_sum = 0; | 
|  | int mv_row_sum = 0; | 
|  | int mv_col_sum = 0; | 
|  | int_mv * const mv = &(mi->bmi[row*4 + col].mv); | 
|  | mv->as_int = 0; | 
|  | for (i = 0; i < NUM_NEIGHBORS; ++i) | 
|  | { | 
|  | /* Calculate the weighted sum of neighboring MVs referring | 
|  | * to the dominant frame type. | 
|  | */ | 
|  | const int w = weights_q7[abs(row - neigh_pos[i].row)] | 
|  | [abs(col - neigh_pos[i].col)]; | 
|  | if (neighbors[i].ref_frame != dom_ref_frame) | 
|  | continue; | 
|  | w_sum += w; | 
|  | /* Q7 * Q3 = Q10 */ | 
|  | mv_row_sum += w*neighbors[i].mv.row; | 
|  | mv_col_sum += w*neighbors[i].mv.col; | 
|  | } | 
|  | if (w_sum > 0) | 
|  | { | 
|  | /* Avoid division by zero. | 
|  | * Normalize with the sum of the coefficients | 
|  | * Q3 = Q10 / Q7 | 
|  | */ | 
|  | mv->as_mv.row = mv_row_sum / w_sum; | 
|  | mv->as_mv.col = mv_col_sum / w_sum; | 
|  | mi->mbmi.need_to_clamp_mvs |= vp8_check_mv_bounds( | 
|  | mv, | 
|  | mb_to_left_edge, | 
|  | mb_to_right_edge, | 
|  | mb_to_top_edge, | 
|  | mb_to_bottom_edge); | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | void vp8_interpolate_motion(MACROBLOCKD *mb, | 
|  | int mb_row, int mb_col, | 
|  | int mb_rows, int mb_cols, | 
|  | int mi_stride) | 
|  | { | 
|  | /* Find relevant neighboring blocks */ | 
|  | EC_BLOCK neighbors[NUM_NEIGHBORS]; | 
|  | int i; | 
|  | /* Initialize the array. MAX_REF_FRAMES is interpreted as "doesn't exist" */ | 
|  | for (i = 0; i < NUM_NEIGHBORS; ++i) | 
|  | { | 
|  | neighbors[i].ref_frame = MAX_REF_FRAMES; | 
|  | neighbors[i].mv.row = neighbors[i].mv.col = 0; | 
|  | } | 
|  | find_neighboring_blocks(mb->mode_info_context, | 
|  | neighbors, | 
|  | mb_row, mb_col, | 
|  | mb_rows, mb_cols, | 
|  | mb->mode_info_stride); | 
|  | /* Interpolate MVs for the missing blocks from the surrounding | 
|  | * blocks which refer to the last frame. */ | 
|  | interpolate_mvs(mb, neighbors, LAST_FRAME); | 
|  |  | 
|  | mb->mode_info_context->mbmi.ref_frame = LAST_FRAME; | 
|  | mb->mode_info_context->mbmi.mode = SPLITMV; | 
|  | mb->mode_info_context->mbmi.uv_mode = DC_PRED; | 
|  | mb->mode_info_context->mbmi.partitioning = 3; | 
|  | mb->mode_info_context->mbmi.segment_id = 0; | 
|  | } | 
|  |  | 
|  | void vp8_conceal_corrupt_mb(MACROBLOCKD *xd) | 
|  | { | 
|  | /* This macroblock has corrupt residual, use the motion compensated | 
|  | image (predictor) for concealment */ | 
|  |  | 
|  | /* The build predictor functions now output directly into the dst buffer, | 
|  | * so the copies are no longer necessary */ | 
|  |  | 
|  | } |