diff options
Diffstat (limited to 'media/libvpx/vp8/decoder/error_concealment.c')
| -rw-r--r-- | media/libvpx/vp8/decoder/error_concealment.c | 596 |
1 files changed, 596 insertions, 0 deletions
diff --git a/media/libvpx/vp8/decoder/error_concealment.c b/media/libvpx/vp8/decoder/error_concealment.c new file mode 100644 index 000000000..bb6d443c4 --- /dev/null +++ b/media/libvpx/vp8/decoder/error_concealment.c @@ -0,0 +1,596 @@ +/* + * 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" +#include "vp8/common/common.h" + +#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; + 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 */ + +} |