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  */
10 
11 #include "vpx_mem/vpx_mem.h"
12 #include "vpx_ports/mem.h"
13 
14 #include "vp9/common/vp9_blockd.h"
15 #include "vp9/common/vp9_common.h"
16 
17 #include "vp9/decoder/vp9_detokenize.h"
18 
19 #define EOB_CONTEXT_NODE            0
20 #define ZERO_CONTEXT_NODE           1
21 #define ONE_CONTEXT_NODE            2
22 #define LOW_VAL_CONTEXT_NODE        0
23 #define TWO_CONTEXT_NODE            1
24 #define THREE_CONTEXT_NODE          2
25 #define HIGH_LOW_CONTEXT_NODE       3
26 #define CAT_ONE_CONTEXT_NODE        4
27 #define CAT_THREEFOUR_CONTEXT_NODE  5
28 #define CAT_THREE_CONTEXT_NODE      6
29 #define CAT_FIVE_CONTEXT_NODE       7
30 
31 #define INCREMENT_COUNT(token)                              \
32   do {                                                      \
33      if (!cm->frame_parallel_decoding_mode)                 \
34        ++coef_counts[band][ctx][token];                     \
35   } while (0)
36 
37 #define WRITE_COEF_CONTINUE(val, token)                  \
38   {                                                      \
39     v = (val * dqv) >> dq_shift;                         \
40     dqcoeff[scan[c]] = vp9_read_bit(r) ? -v : v;         \
41     token_cache[scan[c]] = vp9_pt_energy_class[token];   \
42     ++c;                                                 \
43     ctx = get_coef_context(nb, token_cache, c);          \
44     dqv = dq[1];                                         \
45     continue;                                            \
46   }
47 
48 #define ADJUST_COEF(prob, bits_count)                   \
49   do {                                                  \
50     val += (vp9_read(r, prob) << bits_count);           \
51   } while (0)
52 
decode_coefs(VP9_COMMON * cm,const MACROBLOCKD * xd,PLANE_TYPE type,int16_t * dqcoeff,TX_SIZE tx_size,const int16_t * dq,int ctx,const int16_t * scan,const int16_t * nb,vp9_reader * r)53 static int decode_coefs(VP9_COMMON *cm, const MACROBLOCKD *xd, PLANE_TYPE type,
54                        int16_t *dqcoeff, TX_SIZE tx_size, const int16_t *dq,
55                        int ctx, const int16_t *scan, const int16_t *nb,
56                        vp9_reader *r) {
57   const int max_eob = 16 << (tx_size << 1);
58   const FRAME_CONTEXT *const fc = &cm->fc;
59   FRAME_COUNTS *const counts = &cm->counts;
60   const int ref = is_inter_block(&xd->mi[0]->mbmi);
61   int band, c = 0;
62   const vp9_prob (*coef_probs)[COEFF_CONTEXTS][UNCONSTRAINED_NODES] =
63       fc->coef_probs[tx_size][type][ref];
64   const vp9_prob *prob;
65   unsigned int (*coef_counts)[COEFF_CONTEXTS][UNCONSTRAINED_NODES + 1] =
66       counts->coef[tx_size][type][ref];
67   unsigned int (*eob_branch_count)[COEFF_CONTEXTS] =
68       counts->eob_branch[tx_size][type][ref];
69   uint8_t token_cache[32 * 32];
70   const uint8_t *band_translate = get_band_translate(tx_size);
71   const int dq_shift = (tx_size == TX_32X32);
72   int v;
73   int16_t dqv = dq[0];
74 
75   while (c < max_eob) {
76     int val;
77     band = *band_translate++;
78     prob = coef_probs[band][ctx];
79     if (!cm->frame_parallel_decoding_mode)
80       ++eob_branch_count[band][ctx];
81     if (!vp9_read(r, prob[EOB_CONTEXT_NODE])) {
82       INCREMENT_COUNT(EOB_MODEL_TOKEN);
83       break;
84     }
85 
86     while (!vp9_read(r, prob[ZERO_CONTEXT_NODE])) {
87       INCREMENT_COUNT(ZERO_TOKEN);
88       dqv = dq[1];
89       token_cache[scan[c]] = 0;
90       ++c;
91       if (c >= max_eob)
92         return c;  // zero tokens at the end (no eob token)
93       ctx = get_coef_context(nb, token_cache, c);
94       band = *band_translate++;
95       prob = coef_probs[band][ctx];
96     }
97 
98     // ONE_CONTEXT_NODE_0_
99     if (!vp9_read(r, prob[ONE_CONTEXT_NODE])) {
100       INCREMENT_COUNT(ONE_TOKEN);
101       WRITE_COEF_CONTINUE(1, ONE_TOKEN);
102     }
103 
104     INCREMENT_COUNT(TWO_TOKEN);
105 
106     prob = vp9_pareto8_full[prob[PIVOT_NODE] - 1];
107 
108     if (!vp9_read(r, prob[LOW_VAL_CONTEXT_NODE])) {
109       if (!vp9_read(r, prob[TWO_CONTEXT_NODE])) {
110         WRITE_COEF_CONTINUE(2, TWO_TOKEN);
111       }
112       if (!vp9_read(r, prob[THREE_CONTEXT_NODE])) {
113         WRITE_COEF_CONTINUE(3, THREE_TOKEN);
114       }
115       WRITE_COEF_CONTINUE(4, FOUR_TOKEN);
116     }
117 
118     if (!vp9_read(r, prob[HIGH_LOW_CONTEXT_NODE])) {
119       if (!vp9_read(r, prob[CAT_ONE_CONTEXT_NODE])) {
120         val = CAT1_MIN_VAL;
121         ADJUST_COEF(vp9_cat1_prob[0], 0);
122         WRITE_COEF_CONTINUE(val, CATEGORY1_TOKEN);
123       }
124       val = CAT2_MIN_VAL;
125       ADJUST_COEF(vp9_cat2_prob[0], 1);
126       ADJUST_COEF(vp9_cat2_prob[1], 0);
127       WRITE_COEF_CONTINUE(val, CATEGORY2_TOKEN);
128     }
129 
130     if (!vp9_read(r, prob[CAT_THREEFOUR_CONTEXT_NODE])) {
131       if (!vp9_read(r, prob[CAT_THREE_CONTEXT_NODE])) {
132         val = CAT3_MIN_VAL;
133         ADJUST_COEF(vp9_cat3_prob[0], 2);
134         ADJUST_COEF(vp9_cat3_prob[1], 1);
135         ADJUST_COEF(vp9_cat3_prob[2], 0);
136         WRITE_COEF_CONTINUE(val, CATEGORY3_TOKEN);
137       }
138       val = CAT4_MIN_VAL;
139       ADJUST_COEF(vp9_cat4_prob[0], 3);
140       ADJUST_COEF(vp9_cat4_prob[1], 2);
141       ADJUST_COEF(vp9_cat4_prob[2], 1);
142       ADJUST_COEF(vp9_cat4_prob[3], 0);
143       WRITE_COEF_CONTINUE(val, CATEGORY4_TOKEN);
144     }
145 
146     if (!vp9_read(r, prob[CAT_FIVE_CONTEXT_NODE])) {
147       val = CAT5_MIN_VAL;
148       ADJUST_COEF(vp9_cat5_prob[0], 4);
149       ADJUST_COEF(vp9_cat5_prob[1], 3);
150       ADJUST_COEF(vp9_cat5_prob[2], 2);
151       ADJUST_COEF(vp9_cat5_prob[3], 1);
152       ADJUST_COEF(vp9_cat5_prob[4], 0);
153       WRITE_COEF_CONTINUE(val, CATEGORY5_TOKEN);
154     }
155     val = 0;
156     val = (val << 1) | vp9_read(r, vp9_cat6_prob[0]);
157     val = (val << 1) | vp9_read(r, vp9_cat6_prob[1]);
158     val = (val << 1) | vp9_read(r, vp9_cat6_prob[2]);
159     val = (val << 1) | vp9_read(r, vp9_cat6_prob[3]);
160     val = (val << 1) | vp9_read(r, vp9_cat6_prob[4]);
161     val = (val << 1) | vp9_read(r, vp9_cat6_prob[5]);
162     val = (val << 1) | vp9_read(r, vp9_cat6_prob[6]);
163     val = (val << 1) | vp9_read(r, vp9_cat6_prob[7]);
164     val = (val << 1) | vp9_read(r, vp9_cat6_prob[8]);
165     val = (val << 1) | vp9_read(r, vp9_cat6_prob[9]);
166     val = (val << 1) | vp9_read(r, vp9_cat6_prob[10]);
167     val = (val << 1) | vp9_read(r, vp9_cat6_prob[11]);
168     val = (val << 1) | vp9_read(r, vp9_cat6_prob[12]);
169     val = (val << 1) | vp9_read(r, vp9_cat6_prob[13]);
170     val += CAT6_MIN_VAL;
171 
172     WRITE_COEF_CONTINUE(val, CATEGORY6_TOKEN);
173   }
174 
175   return c;
176 }
177 
vp9_decode_block_tokens(VP9_COMMON * cm,MACROBLOCKD * xd,int plane,int block,BLOCK_SIZE plane_bsize,int x,int y,TX_SIZE tx_size,vp9_reader * r)178 int vp9_decode_block_tokens(VP9_COMMON *cm, MACROBLOCKD *xd,
179                             int plane, int block, BLOCK_SIZE plane_bsize,
180                             int x, int y, TX_SIZE tx_size, vp9_reader *r) {
181   struct macroblockd_plane *const pd = &xd->plane[plane];
182   const int ctx = get_entropy_context(tx_size, pd->above_context + x,
183                                                pd->left_context + y);
184   const scan_order *so = get_scan(xd, tx_size, pd->plane_type, block);
185   const int eob = decode_coefs(cm, xd, pd->plane_type,
186                                BLOCK_OFFSET(pd->dqcoeff, block), tx_size,
187                                pd->dequant, ctx, so->scan, so->neighbors, r);
188   vp9_set_contexts(xd, pd, plane_bsize, tx_size, eob > 0, x, y);
189   return eob;
190 }
191 
192 
193