1 /*
2 * Copyright (c) 2011 The WebM project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include <assert.h>
12
13 #include "error_concealment.h"
14 #include "onyxd_int.h"
15 #include "decodemv.h"
16 #include "vpx_mem/vpx_mem.h"
17 #include "vp8/common/findnearmv.h"
18 #include "vp8/common/common.h"
19 #include "vpx_dsp/vpx_dsp_common.h"
20
21 #define FLOOR(x, q) ((x) & -(1 << (q)))
22
23 #define NUM_NEIGHBORS 20
24
25 typedef struct ec_position {
26 int row;
27 int col;
28 } EC_POS;
29
30 /*
31 * Regenerate the table in Matlab with:
32 * x = meshgrid((1:4), (1:4));
33 * y = meshgrid((1:4), (1:4))';
34 * W = round((1./(sqrt(x.^2 + y.^2))*2^7));
35 * W(1,1) = 0;
36 */
37 static const int weights_q7[5][5] = { { 0, 128, 64, 43, 32 },
38 { 128, 91, 57, 40, 31 },
39 { 64, 57, 45, 36, 29 },
40 { 43, 40, 36, 30, 26 },
41 { 32, 31, 29, 26, 23 } };
42
vp8_alloc_overlap_lists(VP8D_COMP * pbi)43 int vp8_alloc_overlap_lists(VP8D_COMP *pbi) {
44 if (pbi->overlaps != NULL) {
45 vpx_free(pbi->overlaps);
46 pbi->overlaps = NULL;
47 }
48
49 pbi->overlaps =
50 vpx_calloc(pbi->common.mb_rows * pbi->common.mb_cols, sizeof(MB_OVERLAP));
51
52 if (pbi->overlaps == NULL) return -1;
53
54 return 0;
55 }
56
vp8_de_alloc_overlap_lists(VP8D_COMP * pbi)57 void vp8_de_alloc_overlap_lists(VP8D_COMP *pbi) {
58 vpx_free(pbi->overlaps);
59 pbi->overlaps = NULL;
60 }
61
62 /* Inserts a new overlap area value to the list of overlaps of a block */
assign_overlap(OVERLAP_NODE * overlaps,union b_mode_info * bmi,int overlap)63 static void assign_overlap(OVERLAP_NODE *overlaps, union b_mode_info *bmi,
64 int overlap) {
65 int i;
66 if (overlap <= 0) return;
67 /* Find and assign to the next empty overlap node in the list of overlaps.
68 * Empty is defined as bmi == NULL */
69 for (i = 0; i < MAX_OVERLAPS; ++i) {
70 if (overlaps[i].bmi == NULL) {
71 overlaps[i].bmi = bmi;
72 overlaps[i].overlap = overlap;
73 break;
74 }
75 }
76 }
77
78 /* Calculates the overlap area between two 4x4 squares, where the first
79 * square has its upper-left corner at (b1_row, b1_col) and the second
80 * square has its upper-left corner at (b2_row, b2_col). Doesn't
81 * properly handle squares which do not overlap.
82 */
block_overlap(int b1_row,int b1_col,int b2_row,int b2_col)83 static int block_overlap(int b1_row, int b1_col, int b2_row, int b2_col) {
84 const int int_top = VPXMAX(b1_row, b2_row); // top
85 const int int_left = VPXMAX(b1_col, b2_col); // left
86 /* Since each block is 4x4 pixels, adding 4 (Q3) to the left/top edge
87 * gives us the right/bottom edge.
88 */
89 const int int_right = VPXMIN(b1_col + (4 << 3), b2_col + (4 << 3)); // right
90 const int int_bottom =
91 VPXMIN(b1_row + (4 << 3), b2_row + (4 << 3)); // bottom
92 return (int_bottom - int_top) * (int_right - int_left);
93 }
94
95 /* Calculates the overlap area for all blocks in a macroblock at position
96 * (mb_row, mb_col) in macroblocks, which are being overlapped by a given
97 * overlapping block at position (new_row, new_col) (in pixels, Q3). The
98 * first block being overlapped in the macroblock has position (first_blk_row,
99 * first_blk_col) in blocks relative the upper-left corner of the image.
100 */
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)101 static void calculate_overlaps_mb(B_OVERLAP *b_overlaps, union b_mode_info *bmi,
102 int new_row, int new_col, int mb_row,
103 int mb_col, int first_blk_row,
104 int first_blk_col) {
105 /* Find the blocks within this MB (defined by mb_row, mb_col) which are
106 * overlapped by bmi and calculate and assign overlap for each of those
107 * blocks. */
108
109 /* Block coordinates relative the upper-left block */
110 const int rel_ol_blk_row = first_blk_row - mb_row * 4;
111 const int rel_ol_blk_col = first_blk_col - mb_col * 4;
112 /* If the block partly overlaps any previous MB, these coordinates
113 * can be < 0. We don't want to access blocks in previous MBs.
114 */
115 const int blk_idx = VPXMAX(rel_ol_blk_row, 0) * 4 + VPXMAX(rel_ol_blk_col, 0);
116 /* Upper left overlapping block */
117 B_OVERLAP *b_ol_ul = &(b_overlaps[blk_idx]);
118
119 /* Calculate and assign overlaps for all blocks in this MB
120 * which the motion compensated block overlaps
121 */
122 /* Avoid calculating overlaps for blocks in later MBs */
123 int end_row = VPXMIN(4 + mb_row * 4 - first_blk_row, 2);
124 int end_col = VPXMIN(4 + mb_col * 4 - first_blk_col, 2);
125 int row, col;
126
127 /* Check if new_row and new_col are evenly divisible by 4 (Q3),
128 * and if so we shouldn't check neighboring blocks
129 */
130 if (new_row >= 0 && (new_row & 0x1F) == 0) end_row = 1;
131 if (new_col >= 0 && (new_col & 0x1F) == 0) end_col = 1;
132
133 /* Check if the overlapping block partly overlaps a previous MB
134 * and if so, we're overlapping fewer blocks in this MB.
135 */
136 if (new_row < (mb_row * 16) << 3) end_row = 1;
137 if (new_col < (mb_col * 16) << 3) end_col = 1;
138
139 for (row = 0; row < end_row; ++row) {
140 for (col = 0; col < end_col; ++col) {
141 /* input in Q3, result in Q6 */
142 const int overlap =
143 block_overlap(new_row, new_col, (((first_blk_row + row) * 4) << 3),
144 (((first_blk_col + col) * 4) << 3));
145 assign_overlap(b_ol_ul[row * 4 + col].overlaps, bmi, overlap);
146 }
147 }
148 }
149
calculate_overlaps(MB_OVERLAP * overlap_ul,int mb_rows,int mb_cols,union b_mode_info * bmi,int b_row,int b_col)150 static void calculate_overlaps(MB_OVERLAP *overlap_ul, int mb_rows, int mb_cols,
151 union b_mode_info *bmi, int b_row, int b_col) {
152 MB_OVERLAP *mb_overlap;
153 int row, col, rel_row, rel_col;
154 int new_row, new_col;
155 int end_row, end_col;
156 int overlap_b_row, overlap_b_col;
157 int overlap_mb_row, overlap_mb_col;
158
159 /* mb subpixel position */
160 row = (4 * b_row) << 3; /* Q3 */
161 col = (4 * b_col) << 3; /* Q3 */
162
163 /* reverse compensate for motion */
164 new_row = row - bmi->mv.as_mv.row;
165 new_col = col - bmi->mv.as_mv.col;
166
167 if (new_row >= ((16 * mb_rows) << 3) || new_col >= ((16 * mb_cols) << 3)) {
168 /* the new block ended up outside the frame */
169 return;
170 }
171
172 if (new_row <= -32 || new_col <= -32) {
173 /* outside the frame */
174 return;
175 }
176 /* overlapping block's position in blocks */
177 overlap_b_row = FLOOR(new_row / 4, 3) >> 3;
178 overlap_b_col = FLOOR(new_col / 4, 3) >> 3;
179
180 /* overlapping block's MB position in MBs
181 * operations are done in Q3
182 */
183 overlap_mb_row = FLOOR((overlap_b_row << 3) / 4, 3) >> 3;
184 overlap_mb_col = FLOOR((overlap_b_col << 3) / 4, 3) >> 3;
185
186 end_row = VPXMIN(mb_rows - overlap_mb_row, 2);
187 end_col = VPXMIN(mb_cols - overlap_mb_col, 2);
188
189 /* Don't calculate overlap for MBs we don't overlap */
190 /* Check if the new block row starts at the last block row of the MB */
191 if (abs(new_row - ((16 * overlap_mb_row) << 3)) < ((3 * 4) << 3)) end_row = 1;
192 /* Check if the new block col starts at the last block col of the MB */
193 if (abs(new_col - ((16 * overlap_mb_col) << 3)) < ((3 * 4) << 3)) end_col = 1;
194
195 /* find the MB(s) this block is overlapping */
196 for (rel_row = 0; rel_row < end_row; ++rel_row) {
197 for (rel_col = 0; rel_col < end_col; ++rel_col) {
198 if (overlap_mb_row + rel_row < 0 || overlap_mb_col + rel_col < 0)
199 continue;
200 mb_overlap = overlap_ul + (overlap_mb_row + rel_row) * mb_cols +
201 overlap_mb_col + rel_col;
202
203 calculate_overlaps_mb(mb_overlap->overlaps, bmi, new_row, new_col,
204 overlap_mb_row + rel_row, overlap_mb_col + rel_col,
205 overlap_b_row + rel_row, overlap_b_col + rel_col);
206 }
207 }
208 }
209
210 /* Estimates a motion vector given the overlapping blocks' motion vectors.
211 * Filters out all overlapping blocks which do not refer to the correct
212 * reference frame type.
213 */
estimate_mv(const OVERLAP_NODE * overlaps,union b_mode_info * bmi)214 static void estimate_mv(const OVERLAP_NODE *overlaps, union b_mode_info *bmi) {
215 int i;
216 int overlap_sum = 0;
217 int row_acc = 0;
218 int col_acc = 0;
219
220 bmi->mv.as_int = 0;
221 for (i = 0; i < MAX_OVERLAPS; ++i) {
222 if (overlaps[i].bmi == NULL) break;
223 col_acc += overlaps[i].overlap * overlaps[i].bmi->mv.as_mv.col;
224 row_acc += overlaps[i].overlap * overlaps[i].bmi->mv.as_mv.row;
225 overlap_sum += overlaps[i].overlap;
226 }
227 if (overlap_sum > 0) {
228 /* Q9 / Q6 = Q3 */
229 bmi->mv.as_mv.col = col_acc / overlap_sum;
230 bmi->mv.as_mv.row = row_acc / overlap_sum;
231 } else {
232 bmi->mv.as_mv.col = 0;
233 bmi->mv.as_mv.row = 0;
234 }
235 }
236
237 /* Estimates all motion vectors for a macroblock given the lists of
238 * overlaps for each block. Decides whether or not the MVs must be clamped.
239 */
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)240 static void estimate_mb_mvs(const B_OVERLAP *block_overlaps, MODE_INFO *mi,
241 int mb_to_left_edge, int mb_to_right_edge,
242 int mb_to_top_edge, int mb_to_bottom_edge) {
243 int row, col;
244 int non_zero_count = 0;
245 MV *const filtered_mv = &(mi->mbmi.mv.as_mv);
246 union b_mode_info *const bmi = mi->bmi;
247 filtered_mv->col = 0;
248 filtered_mv->row = 0;
249 mi->mbmi.need_to_clamp_mvs = 0;
250 for (row = 0; row < 4; ++row) {
251 int this_b_to_top_edge = mb_to_top_edge + ((row * 4) << 3);
252 int this_b_to_bottom_edge = mb_to_bottom_edge - ((row * 4) << 3);
253 for (col = 0; col < 4; ++col) {
254 int i = row * 4 + col;
255 int this_b_to_left_edge = mb_to_left_edge + ((col * 4) << 3);
256 int this_b_to_right_edge = mb_to_right_edge - ((col * 4) << 3);
257 /* Estimate vectors for all blocks which are overlapped by this */
258 /* type. Interpolate/extrapolate the rest of the block's MVs */
259 estimate_mv(block_overlaps[i].overlaps, &(bmi[i]));
260 mi->mbmi.need_to_clamp_mvs |= vp8_check_mv_bounds(
261 &bmi[i].mv, this_b_to_left_edge, this_b_to_right_edge,
262 this_b_to_top_edge, this_b_to_bottom_edge);
263 if (bmi[i].mv.as_int != 0) {
264 ++non_zero_count;
265 filtered_mv->col += bmi[i].mv.as_mv.col;
266 filtered_mv->row += bmi[i].mv.as_mv.row;
267 }
268 }
269 }
270 if (non_zero_count > 0) {
271 filtered_mv->col /= non_zero_count;
272 filtered_mv->row /= non_zero_count;
273 }
274 }
275
calc_prev_mb_overlaps(MB_OVERLAP * overlaps,MODE_INFO * prev_mi,int mb_row,int mb_col,int mb_rows,int mb_cols)276 static void calc_prev_mb_overlaps(MB_OVERLAP *overlaps, MODE_INFO *prev_mi,
277 int mb_row, int mb_col, int mb_rows,
278 int mb_cols) {
279 int sub_row;
280 int sub_col;
281 for (sub_row = 0; sub_row < 4; ++sub_row) {
282 for (sub_col = 0; sub_col < 4; ++sub_col) {
283 calculate_overlaps(overlaps, mb_rows, mb_cols,
284 &(prev_mi->bmi[sub_row * 4 + sub_col]),
285 4 * mb_row + sub_row, 4 * mb_col + sub_col);
286 }
287 }
288 }
289
290 /* Estimate all missing motion vectors. This function does the same as the one
291 * above, but has different input arguments. */
estimate_missing_mvs(MB_OVERLAP * overlaps,MODE_INFO * mi,MODE_INFO * prev_mi,int mb_rows,int mb_cols,unsigned int first_corrupt)292 static void estimate_missing_mvs(MB_OVERLAP *overlaps, MODE_INFO *mi,
293 MODE_INFO *prev_mi, int mb_rows, int mb_cols,
294 unsigned int first_corrupt) {
295 int mb_row, mb_col;
296 memset(overlaps, 0, sizeof(MB_OVERLAP) * mb_rows * mb_cols);
297 /* First calculate the overlaps for all blocks */
298 for (mb_row = 0; mb_row < mb_rows; ++mb_row) {
299 for (mb_col = 0; mb_col < mb_cols; ++mb_col) {
300 /* We're only able to use blocks referring to the last frame
301 * when extrapolating new vectors.
302 */
303 if (prev_mi->mbmi.ref_frame == LAST_FRAME) {
304 calc_prev_mb_overlaps(overlaps, prev_mi, mb_row, mb_col, mb_rows,
305 mb_cols);
306 }
307 ++prev_mi;
308 }
309 ++prev_mi;
310 }
311
312 mb_row = first_corrupt / mb_cols;
313 mb_col = first_corrupt - mb_row * mb_cols;
314 mi += mb_row * (mb_cols + 1) + mb_col;
315 /* Go through all macroblocks in the current image with missing MVs
316 * and calculate new MVs using the overlaps.
317 */
318 for (; mb_row < mb_rows; ++mb_row) {
319 int mb_to_top_edge = -((mb_row * 16)) << 3;
320 int mb_to_bottom_edge = ((mb_rows - 1 - mb_row) * 16) << 3;
321 for (; mb_col < mb_cols; ++mb_col) {
322 int mb_to_left_edge = -((mb_col * 16) << 3);
323 int mb_to_right_edge = ((mb_cols - 1 - mb_col) * 16) << 3;
324 const B_OVERLAP *block_overlaps =
325 overlaps[mb_row * mb_cols + mb_col].overlaps;
326 mi->mbmi.ref_frame = LAST_FRAME;
327 mi->mbmi.mode = SPLITMV;
328 mi->mbmi.uv_mode = DC_PRED;
329 mi->mbmi.partitioning = 3;
330 mi->mbmi.segment_id = 0;
331 estimate_mb_mvs(block_overlaps, mi, mb_to_left_edge, mb_to_right_edge,
332 mb_to_top_edge, mb_to_bottom_edge);
333 ++mi;
334 }
335 mb_col = 0;
336 ++mi;
337 }
338 }
339
vp8_estimate_missing_mvs(VP8D_COMP * pbi)340 void vp8_estimate_missing_mvs(VP8D_COMP *pbi) {
341 VP8_COMMON *const pc = &pbi->common;
342 estimate_missing_mvs(pbi->overlaps, pc->mi, pc->prev_mi, pc->mb_rows,
343 pc->mb_cols, pbi->mvs_corrupt_from_mb);
344 }
345
assign_neighbor(EC_BLOCK * neighbor,MODE_INFO * mi,int block_idx)346 static void assign_neighbor(EC_BLOCK *neighbor, MODE_INFO *mi, int block_idx) {
347 assert(mi->mbmi.ref_frame < MAX_REF_FRAMES);
348 neighbor->ref_frame = mi->mbmi.ref_frame;
349 neighbor->mv = mi->bmi[block_idx].mv.as_mv;
350 }
351
352 /* Finds the neighboring blocks of a macroblocks. In the general case
353 * 20 blocks are found. If a fewer number of blocks are found due to
354 * image boundaries, those positions in the EC_BLOCK array are left "empty".
355 * The neighbors are enumerated with the upper-left neighbor as the first
356 * element, the second element refers to the neighbor to right of the previous
357 * neighbor, and so on. The last element refers to the neighbor below the first
358 * neighbor.
359 */
find_neighboring_blocks(MODE_INFO * mi,EC_BLOCK * neighbors,int mb_row,int mb_col,int mb_rows,int mb_cols,int mi_stride)360 static void find_neighboring_blocks(MODE_INFO *mi, EC_BLOCK *neighbors,
361 int mb_row, int mb_col, int mb_rows,
362 int mb_cols, int mi_stride) {
363 int i = 0;
364 int j;
365 if (mb_row > 0) {
366 /* upper left */
367 if (mb_col > 0) assign_neighbor(&neighbors[i], mi - mi_stride - 1, 15);
368 ++i;
369 /* above */
370 for (j = 12; j < 16; ++j, ++i)
371 assign_neighbor(&neighbors[i], mi - mi_stride, j);
372 } else
373 i += 5;
374 if (mb_col < mb_cols - 1) {
375 /* upper right */
376 if (mb_row > 0) assign_neighbor(&neighbors[i], mi - mi_stride + 1, 12);
377 ++i;
378 /* right */
379 for (j = 0; j <= 12; j += 4, ++i) assign_neighbor(&neighbors[i], mi + 1, j);
380 } else
381 i += 5;
382 if (mb_row < mb_rows - 1) {
383 /* lower right */
384 if (mb_col < mb_cols - 1)
385 assign_neighbor(&neighbors[i], mi + mi_stride + 1, 0);
386 ++i;
387 /* below */
388 for (j = 0; j < 4; ++j, ++i)
389 assign_neighbor(&neighbors[i], mi + mi_stride, j);
390 } else
391 i += 5;
392 if (mb_col > 0) {
393 /* lower left */
394 if (mb_row < mb_rows - 1)
395 assign_neighbor(&neighbors[i], mi + mi_stride - 1, 4);
396 ++i;
397 /* left */
398 for (j = 3; j < 16; j += 4, ++i) {
399 assign_neighbor(&neighbors[i], mi - 1, j);
400 }
401 } else
402 i += 5;
403 assert(i == 20);
404 }
405
406 /* Interpolates all motion vectors for a macroblock from the neighboring blocks'
407 * motion vectors.
408 */
interpolate_mvs(MACROBLOCKD * mb,EC_BLOCK * neighbors,MV_REFERENCE_FRAME dom_ref_frame)409 static void interpolate_mvs(MACROBLOCKD *mb, EC_BLOCK *neighbors,
410 MV_REFERENCE_FRAME dom_ref_frame) {
411 int row, col, i;
412 MODE_INFO *const mi = mb->mode_info_context;
413 /* Table with the position of the neighboring blocks relative the position
414 * of the upper left block of the current MB. Starting with the upper left
415 * neighbor and going to the right.
416 */
417 const EC_POS neigh_pos[NUM_NEIGHBORS] = {
418 { -1, -1 }, { -1, 0 }, { -1, 1 }, { -1, 2 }, { -1, 3 }, { -1, 4 }, { 0, 4 },
419 { 1, 4 }, { 2, 4 }, { 3, 4 }, { 4, 4 }, { 4, 3 }, { 4, 2 }, { 4, 1 },
420 { 4, 0 }, { 4, -1 }, { 3, -1 }, { 2, -1 }, { 1, -1 }, { 0, -1 }
421 };
422 mi->mbmi.need_to_clamp_mvs = 0;
423 for (row = 0; row < 4; ++row) {
424 int mb_to_top_edge = mb->mb_to_top_edge + ((row * 4) << 3);
425 int mb_to_bottom_edge = mb->mb_to_bottom_edge - ((row * 4) << 3);
426 for (col = 0; col < 4; ++col) {
427 int mb_to_left_edge = mb->mb_to_left_edge + ((col * 4) << 3);
428 int mb_to_right_edge = mb->mb_to_right_edge - ((col * 4) << 3);
429 int w_sum = 0;
430 int mv_row_sum = 0;
431 int mv_col_sum = 0;
432 int_mv *const mv = &(mi->bmi[row * 4 + col].mv);
433 mv->as_int = 0;
434 for (i = 0; i < NUM_NEIGHBORS; ++i) {
435 /* Calculate the weighted sum of neighboring MVs referring
436 * to the dominant frame type.
437 */
438 const int w = weights_q7[abs(row - neigh_pos[i].row)]
439 [abs(col - neigh_pos[i].col)];
440 if (neighbors[i].ref_frame != dom_ref_frame) continue;
441 w_sum += w;
442 /* Q7 * Q3 = Q10 */
443 mv_row_sum += w * neighbors[i].mv.row;
444 mv_col_sum += w * neighbors[i].mv.col;
445 }
446 if (w_sum > 0) {
447 /* Avoid division by zero.
448 * Normalize with the sum of the coefficients
449 * Q3 = Q10 / Q7
450 */
451 mv->as_mv.row = mv_row_sum / w_sum;
452 mv->as_mv.col = mv_col_sum / w_sum;
453 mi->mbmi.need_to_clamp_mvs |=
454 vp8_check_mv_bounds(mv, mb_to_left_edge, mb_to_right_edge,
455 mb_to_top_edge, mb_to_bottom_edge);
456 }
457 }
458 }
459 }
460
vp8_interpolate_motion(MACROBLOCKD * mb,int mb_row,int mb_col,int mb_rows,int mb_cols)461 void vp8_interpolate_motion(MACROBLOCKD *mb, int mb_row, int mb_col,
462 int mb_rows, int mb_cols) {
463 /* Find relevant neighboring blocks */
464 EC_BLOCK neighbors[NUM_NEIGHBORS];
465 int i;
466 /* Initialize the array. MAX_REF_FRAMES is interpreted as "doesn't exist" */
467 for (i = 0; i < NUM_NEIGHBORS; ++i) {
468 neighbors[i].ref_frame = MAX_REF_FRAMES;
469 neighbors[i].mv.row = neighbors[i].mv.col = 0;
470 }
471 find_neighboring_blocks(mb->mode_info_context, neighbors, mb_row, mb_col,
472 mb_rows, mb_cols, mb->mode_info_stride);
473 /* Interpolate MVs for the missing blocks from the surrounding
474 * blocks which refer to the last frame. */
475 interpolate_mvs(mb, neighbors, LAST_FRAME);
476
477 mb->mode_info_context->mbmi.ref_frame = LAST_FRAME;
478 mb->mode_info_context->mbmi.mode = SPLITMV;
479 mb->mode_info_context->mbmi.uv_mode = DC_PRED;
480 mb->mode_info_context->mbmi.partitioning = 3;
481 mb->mode_info_context->mbmi.segment_id = 0;
482 }
483