• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  *  Copyright (c) 2012 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 
12 #include <limits.h>
13 
14 #include "vpx_mem/vpx_mem.h"
15 
16 #include "vp9/common/vp9_pred_common.h"
17 #include "vp9/common/vp9_tile_common.h"
18 
19 #include "vp9/encoder/vp9_cost.h"
20 #include "vp9/encoder/vp9_segmentation.h"
21 
vp9_enable_segmentation(struct segmentation * seg)22 void vp9_enable_segmentation(struct segmentation *seg) {
23   seg->enabled = 1;
24   seg->update_map = 1;
25   seg->update_data = 1;
26 }
27 
vp9_disable_segmentation(struct segmentation * seg)28 void vp9_disable_segmentation(struct segmentation *seg) {
29   seg->enabled = 0;
30 }
31 
vp9_set_segmentation_map(VP9_COMP * cpi,unsigned char * segmentation_map)32 void vp9_set_segmentation_map(VP9_COMP *cpi, unsigned char *segmentation_map) {
33   struct segmentation *const seg = &cpi->common.seg;
34 
35   // Copy in the new segmentation map
36   vpx_memcpy(cpi->segmentation_map, segmentation_map,
37              (cpi->common.mi_rows * cpi->common.mi_cols));
38 
39   // Signal that the map should be updated.
40   seg->update_map = 1;
41   seg->update_data = 1;
42 }
43 
vp9_set_segment_data(struct segmentation * seg,signed char * feature_data,unsigned char abs_delta)44 void vp9_set_segment_data(struct segmentation *seg,
45                           signed char *feature_data,
46                           unsigned char abs_delta) {
47   seg->abs_delta = abs_delta;
48 
49   vpx_memcpy(seg->feature_data, feature_data, sizeof(seg->feature_data));
50 
51   // TBD ?? Set the feature mask
52   // vpx_memcpy(cpi->mb.e_mbd.segment_feature_mask, 0,
53   //            sizeof(cpi->mb.e_mbd.segment_feature_mask));
54 }
vp9_disable_segfeature(struct segmentation * seg,int segment_id,SEG_LVL_FEATURES feature_id)55 void vp9_disable_segfeature(struct segmentation *seg, int segment_id,
56                             SEG_LVL_FEATURES feature_id) {
57   seg->feature_mask[segment_id] &= ~(1 << feature_id);
58 }
59 
vp9_clear_segdata(struct segmentation * seg,int segment_id,SEG_LVL_FEATURES feature_id)60 void vp9_clear_segdata(struct segmentation *seg, int segment_id,
61                        SEG_LVL_FEATURES feature_id) {
62   seg->feature_data[segment_id][feature_id] = 0;
63 }
64 
65 // Based on set of segment counts calculate a probability tree
calc_segtree_probs(int * segcounts,vp9_prob * segment_tree_probs)66 static void calc_segtree_probs(int *segcounts, vp9_prob *segment_tree_probs) {
67   // Work out probabilities of each segment
68   const int c01 = segcounts[0] + segcounts[1];
69   const int c23 = segcounts[2] + segcounts[3];
70   const int c45 = segcounts[4] + segcounts[5];
71   const int c67 = segcounts[6] + segcounts[7];
72 
73   segment_tree_probs[0] = get_binary_prob(c01 + c23, c45 + c67);
74   segment_tree_probs[1] = get_binary_prob(c01, c23);
75   segment_tree_probs[2] = get_binary_prob(c45, c67);
76   segment_tree_probs[3] = get_binary_prob(segcounts[0], segcounts[1]);
77   segment_tree_probs[4] = get_binary_prob(segcounts[2], segcounts[3]);
78   segment_tree_probs[5] = get_binary_prob(segcounts[4], segcounts[5]);
79   segment_tree_probs[6] = get_binary_prob(segcounts[6], segcounts[7]);
80 }
81 
82 // Based on set of segment counts and probabilities calculate a cost estimate
cost_segmap(int * segcounts,vp9_prob * probs)83 static int cost_segmap(int *segcounts, vp9_prob *probs) {
84   const int c01 = segcounts[0] + segcounts[1];
85   const int c23 = segcounts[2] + segcounts[3];
86   const int c45 = segcounts[4] + segcounts[5];
87   const int c67 = segcounts[6] + segcounts[7];
88   const int c0123 = c01 + c23;
89   const int c4567 = c45 + c67;
90 
91   // Cost the top node of the tree
92   int cost = c0123 * vp9_cost_zero(probs[0]) +
93              c4567 * vp9_cost_one(probs[0]);
94 
95   // Cost subsequent levels
96   if (c0123 > 0) {
97     cost += c01 * vp9_cost_zero(probs[1]) +
98             c23 * vp9_cost_one(probs[1]);
99 
100     if (c01 > 0)
101       cost += segcounts[0] * vp9_cost_zero(probs[3]) +
102               segcounts[1] * vp9_cost_one(probs[3]);
103     if (c23 > 0)
104       cost += segcounts[2] * vp9_cost_zero(probs[4]) +
105               segcounts[3] * vp9_cost_one(probs[4]);
106   }
107 
108   if (c4567 > 0) {
109     cost += c45 * vp9_cost_zero(probs[2]) +
110             c67 * vp9_cost_one(probs[2]);
111 
112     if (c45 > 0)
113       cost += segcounts[4] * vp9_cost_zero(probs[5]) +
114               segcounts[5] * vp9_cost_one(probs[5]);
115     if (c67 > 0)
116       cost += segcounts[6] * vp9_cost_zero(probs[6]) +
117               segcounts[7] * vp9_cost_one(probs[6]);
118   }
119 
120   return cost;
121 }
122 
count_segs(VP9_COMP * cpi,const TileInfo * const tile,MODE_INFO ** mi_8x8,int * no_pred_segcounts,int (* temporal_predictor_count)[2],int * t_unpred_seg_counts,int bw,int bh,int mi_row,int mi_col)123 static void count_segs(VP9_COMP *cpi, const TileInfo *const tile,
124                        MODE_INFO **mi_8x8,
125                        int *no_pred_segcounts,
126                        int (*temporal_predictor_count)[2],
127                        int *t_unpred_seg_counts,
128                        int bw, int bh, int mi_row, int mi_col) {
129   VP9_COMMON *const cm = &cpi->common;
130   MACROBLOCKD *const xd = &cpi->mb.e_mbd;
131   int segment_id;
132 
133   if (mi_row >= cm->mi_rows || mi_col >= cm->mi_cols)
134     return;
135 
136   xd->mi = mi_8x8;
137   segment_id = xd->mi[0]->mbmi.segment_id;
138 
139   set_mi_row_col(xd, tile, mi_row, bh, mi_col, bw, cm->mi_rows, cm->mi_cols);
140 
141   // Count the number of hits on each segment with no prediction
142   no_pred_segcounts[segment_id]++;
143 
144   // Temporal prediction not allowed on key frames
145   if (cm->frame_type != KEY_FRAME) {
146     const BLOCK_SIZE bsize = mi_8x8[0]->mbmi.sb_type;
147     // Test to see if the segment id matches the predicted value.
148     const int pred_segment_id = vp9_get_segment_id(cm, cm->last_frame_seg_map,
149                                                    bsize, mi_row, mi_col);
150     const int pred_flag = pred_segment_id == segment_id;
151     const int pred_context = vp9_get_pred_context_seg_id(xd);
152 
153     // Store the prediction status for this mb and update counts
154     // as appropriate
155     xd->mi[0]->mbmi.seg_id_predicted = pred_flag;
156     temporal_predictor_count[pred_context][pred_flag]++;
157 
158     if (!pred_flag)
159       // Update the "unpredicted" segment count
160       t_unpred_seg_counts[segment_id]++;
161   }
162 }
163 
count_segs_sb(VP9_COMP * cpi,const TileInfo * const tile,MODE_INFO ** mi_8x8,int * no_pred_segcounts,int (* temporal_predictor_count)[2],int * t_unpred_seg_counts,int mi_row,int mi_col,BLOCK_SIZE bsize)164 static void count_segs_sb(VP9_COMP *cpi, const TileInfo *const tile,
165                           MODE_INFO **mi_8x8,
166                           int *no_pred_segcounts,
167                           int (*temporal_predictor_count)[2],
168                           int *t_unpred_seg_counts,
169                           int mi_row, int mi_col,
170                           BLOCK_SIZE bsize) {
171   const VP9_COMMON *const cm = &cpi->common;
172   const int mis = cm->mi_stride;
173   int bw, bh;
174   const int bs = num_8x8_blocks_wide_lookup[bsize], hbs = bs / 2;
175 
176   if (mi_row >= cm->mi_rows || mi_col >= cm->mi_cols)
177     return;
178 
179   bw = num_8x8_blocks_wide_lookup[mi_8x8[0]->mbmi.sb_type];
180   bh = num_8x8_blocks_high_lookup[mi_8x8[0]->mbmi.sb_type];
181 
182   if (bw == bs && bh == bs) {
183     count_segs(cpi, tile, mi_8x8, no_pred_segcounts, temporal_predictor_count,
184                t_unpred_seg_counts, bs, bs, mi_row, mi_col);
185   } else if (bw == bs && bh < bs) {
186     count_segs(cpi, tile, mi_8x8, no_pred_segcounts, temporal_predictor_count,
187                t_unpred_seg_counts, bs, hbs, mi_row, mi_col);
188     count_segs(cpi, tile, mi_8x8 + hbs * mis, no_pred_segcounts,
189                temporal_predictor_count, t_unpred_seg_counts, bs, hbs,
190                mi_row + hbs, mi_col);
191   } else if (bw < bs && bh == bs) {
192     count_segs(cpi, tile, mi_8x8, no_pred_segcounts, temporal_predictor_count,
193                t_unpred_seg_counts, hbs, bs, mi_row, mi_col);
194     count_segs(cpi, tile, mi_8x8 + hbs,
195                no_pred_segcounts, temporal_predictor_count, t_unpred_seg_counts,
196                hbs, bs, mi_row, mi_col + hbs);
197   } else {
198     const BLOCK_SIZE subsize = subsize_lookup[PARTITION_SPLIT][bsize];
199     int n;
200 
201     assert(bw < bs && bh < bs);
202 
203     for (n = 0; n < 4; n++) {
204       const int mi_dc = hbs * (n & 1);
205       const int mi_dr = hbs * (n >> 1);
206 
207       count_segs_sb(cpi, tile, &mi_8x8[mi_dr * mis + mi_dc],
208                     no_pred_segcounts, temporal_predictor_count,
209                     t_unpred_seg_counts,
210                     mi_row + mi_dr, mi_col + mi_dc, subsize);
211     }
212   }
213 }
214 
vp9_choose_segmap_coding_method(VP9_COMP * cpi)215 void vp9_choose_segmap_coding_method(VP9_COMP *cpi) {
216   VP9_COMMON *const cm = &cpi->common;
217   struct segmentation *seg = &cm->seg;
218 
219   int no_pred_cost;
220   int t_pred_cost = INT_MAX;
221 
222   int i, tile_col, mi_row, mi_col;
223 
224   int temporal_predictor_count[PREDICTION_PROBS][2] = { { 0 } };
225   int no_pred_segcounts[MAX_SEGMENTS] = { 0 };
226   int t_unpred_seg_counts[MAX_SEGMENTS] = { 0 };
227 
228   vp9_prob no_pred_tree[SEG_TREE_PROBS];
229   vp9_prob t_pred_tree[SEG_TREE_PROBS];
230   vp9_prob t_nopred_prob[PREDICTION_PROBS];
231 
232   const int mis = cm->mi_stride;
233   MODE_INFO **mi_ptr, **mi;
234 
235   // Set default state for the segment tree probabilities and the
236   // temporal coding probabilities
237   vpx_memset(seg->tree_probs, 255, sizeof(seg->tree_probs));
238   vpx_memset(seg->pred_probs, 255, sizeof(seg->pred_probs));
239 
240   // First of all generate stats regarding how well the last segment map
241   // predicts this one
242   for (tile_col = 0; tile_col < 1 << cm->log2_tile_cols; tile_col++) {
243     TileInfo tile;
244 
245     vp9_tile_init(&tile, cm, 0, tile_col);
246     mi_ptr = cm->mi_grid_visible + tile.mi_col_start;
247     for (mi_row = 0; mi_row < cm->mi_rows;
248          mi_row += 8, mi_ptr += 8 * mis) {
249       mi = mi_ptr;
250       for (mi_col = tile.mi_col_start; mi_col < tile.mi_col_end;
251            mi_col += 8, mi += 8)
252         count_segs_sb(cpi, &tile, mi, no_pred_segcounts,
253                       temporal_predictor_count, t_unpred_seg_counts,
254                       mi_row, mi_col, BLOCK_64X64);
255     }
256   }
257 
258   // Work out probability tree for coding segments without prediction
259   // and the cost.
260   calc_segtree_probs(no_pred_segcounts, no_pred_tree);
261   no_pred_cost = cost_segmap(no_pred_segcounts, no_pred_tree);
262 
263   // Key frames cannot use temporal prediction
264   if (!frame_is_intra_only(cm)) {
265     // Work out probability tree for coding those segments not
266     // predicted using the temporal method and the cost.
267     calc_segtree_probs(t_unpred_seg_counts, t_pred_tree);
268     t_pred_cost = cost_segmap(t_unpred_seg_counts, t_pred_tree);
269 
270     // Add in the cost of the signaling for each prediction context.
271     for (i = 0; i < PREDICTION_PROBS; i++) {
272       const int count0 = temporal_predictor_count[i][0];
273       const int count1 = temporal_predictor_count[i][1];
274 
275       t_nopred_prob[i] = get_binary_prob(count0, count1);
276 
277       // Add in the predictor signaling cost
278       t_pred_cost += count0 * vp9_cost_zero(t_nopred_prob[i]) +
279                      count1 * vp9_cost_one(t_nopred_prob[i]);
280     }
281   }
282 
283   // Now choose which coding method to use.
284   if (t_pred_cost < no_pred_cost) {
285     seg->temporal_update = 1;
286     vpx_memcpy(seg->tree_probs, t_pred_tree, sizeof(t_pred_tree));
287     vpx_memcpy(seg->pred_probs, t_nopred_prob, sizeof(t_nopred_prob));
288   } else {
289     seg->temporal_update = 0;
290     vpx_memcpy(seg->tree_probs, no_pred_tree, sizeof(no_pred_tree));
291   }
292 }
293 
vp9_reset_segment_features(struct segmentation * seg)294 void vp9_reset_segment_features(struct segmentation *seg) {
295   // Set up default state for MB feature flags
296   seg->enabled = 0;
297   seg->update_map = 0;
298   seg->update_data = 0;
299   vpx_memset(seg->tree_probs, 255, sizeof(seg->tree_probs));
300   vp9_clearall_segfeatures(seg);
301 }
302