media/libvpx/vp9/encoder/vp9_tokenize.c@ac0c01689b40
media/libvpx/vp9/encoder/vp9_tokenize.c
Thu, 15 Jan 2015 15:59:08 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Thu, 15 Jan 2015 15:59:08 +0100
- branch
- TOR_BUG_9701
- changeset 10
- ac0c01689b40
- permissions
- -rw-r--r--
Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
1 /*
2 * Copyright (c) 2010 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 */
12 #include <math.h>
13 #include <stdio.h>
14 #include <string.h>
15 #include <assert.h>
16 #include "vp9/encoder/vp9_onyx_int.h"
17 #include "vp9/encoder/vp9_tokenize.h"
18 #include "vpx_mem/vpx_mem.h"
20 #include "vp9/common/vp9_pred_common.h"
21 #include "vp9/common/vp9_seg_common.h"
22 #include "vp9/common/vp9_entropy.h"
24 static TOKENVALUE dct_value_tokens[DCT_MAX_VALUE * 2];
25 const TOKENVALUE *vp9_dct_value_tokens_ptr;
26 static int dct_value_cost[DCT_MAX_VALUE * 2];
27 const int *vp9_dct_value_cost_ptr;
29 static void fill_value_tokens() {
30 TOKENVALUE *const t = dct_value_tokens + DCT_MAX_VALUE;
31 const vp9_extra_bit *const e = vp9_extra_bits;
33 int i = -DCT_MAX_VALUE;
34 int sign = 1;
36 do {
37 if (!i)
38 sign = 0;
40 {
41 const int a = sign ? -i : i;
42 int eb = sign;
44 if (a > 4) {
45 int j = 4;
47 while (++j < 11 && e[j].base_val <= a) {}
49 t[i].token = --j;
50 eb |= (a - e[j].base_val) << 1;
51 } else {
52 t[i].token = a;
53 }
54 t[i].extra = eb;
55 }
57 // initialize the cost for extra bits for all possible coefficient value.
58 {
59 int cost = 0;
60 const vp9_extra_bit *p = &vp9_extra_bits[t[i].token];
62 if (p->base_val) {
63 const int extra = t[i].extra;
64 const int length = p->len;
66 if (length)
67 cost += treed_cost(p->tree, p->prob, extra >> 1, length);
69 cost += vp9_cost_bit(vp9_prob_half, extra & 1); /* sign */
70 dct_value_cost[i + DCT_MAX_VALUE] = cost;
71 }
72 }
73 } while (++i < DCT_MAX_VALUE);
75 vp9_dct_value_tokens_ptr = dct_value_tokens + DCT_MAX_VALUE;
76 vp9_dct_value_cost_ptr = dct_value_cost + DCT_MAX_VALUE;
77 }
79 struct tokenize_b_args {
80 VP9_COMP *cpi;
81 MACROBLOCKD *xd;
82 TOKENEXTRA **tp;
83 TX_SIZE tx_size;
84 uint8_t *token_cache;
85 };
87 static void set_entropy_context_b(int plane, int block, BLOCK_SIZE plane_bsize,
88 TX_SIZE tx_size, void *arg) {
89 struct tokenize_b_args* const args = arg;
90 MACROBLOCKD *const xd = args->xd;
91 struct macroblockd_plane *pd = &xd->plane[plane];
92 int aoff, loff;
93 txfrm_block_to_raster_xy(plane_bsize, tx_size, block, &aoff, &loff);
94 set_contexts(xd, pd, plane_bsize, tx_size, pd->eobs[block] > 0, aoff, loff);
95 }
97 static void tokenize_b(int plane, int block, BLOCK_SIZE plane_bsize,
98 TX_SIZE tx_size, void *arg) {
99 struct tokenize_b_args* const args = arg;
100 VP9_COMP *cpi = args->cpi;
101 MACROBLOCKD *xd = args->xd;
102 TOKENEXTRA **tp = args->tp;
103 uint8_t *token_cache = args->token_cache;
104 struct macroblockd_plane *pd = &xd->plane[plane];
105 MB_MODE_INFO *mbmi = &xd->mi_8x8[0]->mbmi;
106 int pt; /* near block/prev token context index */
107 int c = 0, rc = 0;
108 TOKENEXTRA *t = *tp; /* store tokens starting here */
109 const int eob = pd->eobs[block];
110 const PLANE_TYPE type = pd->plane_type;
111 const int16_t *qcoeff_ptr = BLOCK_OFFSET(pd->qcoeff, block);
113 const int segment_id = mbmi->segment_id;
114 const int16_t *scan, *nb;
115 vp9_coeff_count *const counts = cpi->coef_counts[tx_size];
116 vp9_coeff_probs_model *const coef_probs = cpi->common.fc.coef_probs[tx_size];
117 const int ref = is_inter_block(mbmi);
118 const uint8_t *const band_translate = get_band_translate(tx_size);
119 const int seg_eob = get_tx_eob(&cpi->common.seg, segment_id, tx_size);
120 int aoff, loff;
121 txfrm_block_to_raster_xy(plane_bsize, tx_size, block, &aoff, &loff);
123 assert((!type && !plane) || (type && plane));
125 pt = get_entropy_context(tx_size, pd->above_context + aoff,
126 pd->left_context + loff);
127 get_scan(xd, tx_size, type, block, &scan, &nb);
128 c = 0;
129 do {
130 const int band = band_translate[c];
131 int token;
132 int v = 0;
133 rc = scan[c];
134 if (c)
135 pt = get_coef_context(nb, token_cache, c);
136 if (c < eob) {
137 v = qcoeff_ptr[rc];
138 assert(-DCT_MAX_VALUE <= v && v < DCT_MAX_VALUE);
140 t->extra = vp9_dct_value_tokens_ptr[v].extra;
141 token = vp9_dct_value_tokens_ptr[v].token;
142 } else {
143 token = DCT_EOB_TOKEN;
144 }
146 t->token = token;
147 t->context_tree = coef_probs[type][ref][band][pt];
148 t->skip_eob_node = (c > 0) && (token_cache[scan[c - 1]] == 0);
150 assert(vp9_coef_encodings[t->token].len - t->skip_eob_node > 0);
152 ++counts[type][ref][band][pt][token];
153 if (!t->skip_eob_node)
154 ++cpi->common.counts.eob_branch[tx_size][type][ref][band][pt];
156 token_cache[rc] = vp9_pt_energy_class[token];
157 ++t;
158 } while (c < eob && ++c < seg_eob);
160 *tp = t;
162 set_contexts(xd, pd, plane_bsize, tx_size, c > 0, aoff, loff);
163 }
165 struct is_skippable_args {
166 MACROBLOCKD *xd;
167 int *skippable;
168 };
170 static void is_skippable(int plane, int block,
171 BLOCK_SIZE plane_bsize, TX_SIZE tx_size,
172 void *argv) {
173 struct is_skippable_args *args = argv;
174 args->skippable[0] &= (!args->xd->plane[plane].eobs[block]);
175 }
177 int vp9_sb_is_skippable(MACROBLOCKD *xd, BLOCK_SIZE bsize) {
178 int result = 1;
179 struct is_skippable_args args = {xd, &result};
180 foreach_transformed_block(xd, bsize, is_skippable, &args);
181 return result;
182 }
184 int vp9_is_skippable_in_plane(MACROBLOCKD *xd, BLOCK_SIZE bsize,
185 int plane) {
186 int result = 1;
187 struct is_skippable_args args = {xd, &result};
188 foreach_transformed_block_in_plane(xd, bsize, plane, is_skippable, &args);
189 return result;
190 }
192 void vp9_tokenize_sb(VP9_COMP *cpi, TOKENEXTRA **t, int dry_run,
193 BLOCK_SIZE bsize) {
194 VP9_COMMON *const cm = &cpi->common;
195 MACROBLOCKD *const xd = &cpi->mb.e_mbd;
196 MB_MODE_INFO *const mbmi = &xd->mi_8x8[0]->mbmi;
197 TOKENEXTRA *t_backup = *t;
198 const int mb_skip_context = vp9_get_pred_context_mbskip(xd);
199 const int skip_inc = !vp9_segfeature_active(&cm->seg, mbmi->segment_id,
200 SEG_LVL_SKIP);
201 struct tokenize_b_args arg = {cpi, xd, t, mbmi->tx_size, cpi->mb.token_cache};
203 mbmi->skip_coeff = vp9_sb_is_skippable(xd, bsize);
204 if (mbmi->skip_coeff) {
205 if (!dry_run)
206 cm->counts.mbskip[mb_skip_context][1] += skip_inc;
207 reset_skip_context(xd, bsize);
208 if (dry_run)
209 *t = t_backup;
210 return;
211 }
213 if (!dry_run) {
214 cm->counts.mbskip[mb_skip_context][0] += skip_inc;
215 foreach_transformed_block(xd, bsize, tokenize_b, &arg);
216 } else {
217 foreach_transformed_block(xd, bsize, set_entropy_context_b, &arg);
218 *t = t_backup;
219 }
220 }
222 void vp9_tokenize_initialize() {
223 fill_value_tokens();
224 }
