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