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 #ifndef VP9_COMMON_VP9_ENTROPY_H_
12 #define VP9_COMMON_VP9_ENTROPY_H_
13
14 #include "vpx/vpx_integer.h"
15
16 #include "vp9/common/vp9_blockd.h"
17 #include "vp9/common/vp9_common.h"
18 #include "vp9/common/vp9_scan.h"
19
20 #ifdef __cplusplus
21 extern "C" {
22 #endif
23
24 #define DIFF_UPDATE_PROB 252
25
26 // Coefficient token alphabet
27 #define ZERO_TOKEN 0 // 0 Extra Bits 0+0
28 #define ONE_TOKEN 1 // 1 Extra Bits 0+1
29 #define TWO_TOKEN 2 // 2 Extra Bits 0+1
30 #define THREE_TOKEN 3 // 3 Extra Bits 0+1
31 #define FOUR_TOKEN 4 // 4 Extra Bits 0+1
32 #define CATEGORY1_TOKEN 5 // 5-6 Extra Bits 1+1
33 #define CATEGORY2_TOKEN 6 // 7-10 Extra Bits 2+1
34 #define CATEGORY3_TOKEN 7 // 11-18 Extra Bits 3+1
35 #define CATEGORY4_TOKEN 8 // 19-34 Extra Bits 4+1
36 #define CATEGORY5_TOKEN 9 // 35-66 Extra Bits 5+1
37 #define CATEGORY6_TOKEN 10 // 67+ Extra Bits 14+1
38 #define EOB_TOKEN 11 // EOB Extra Bits 0+0
39
40 #define ENTROPY_TOKENS 12
41
42 #define ENTROPY_NODES 11
43
44 DECLARE_ALIGNED(16, extern const uint8_t, vp9_pt_energy_class[ENTROPY_TOKENS]);
45
46 #define CAT1_MIN_VAL 5
47 #define CAT2_MIN_VAL 7
48 #define CAT3_MIN_VAL 11
49 #define CAT4_MIN_VAL 19
50 #define CAT5_MIN_VAL 35
51 #define CAT6_MIN_VAL 67
52
53 // Extra bit probabilities.
54 DECLARE_ALIGNED(16, extern const uint8_t, vp9_cat1_prob[1]);
55 DECLARE_ALIGNED(16, extern const uint8_t, vp9_cat2_prob[2]);
56 DECLARE_ALIGNED(16, extern const uint8_t, vp9_cat3_prob[3]);
57 DECLARE_ALIGNED(16, extern const uint8_t, vp9_cat4_prob[4]);
58 DECLARE_ALIGNED(16, extern const uint8_t, vp9_cat5_prob[5]);
59 DECLARE_ALIGNED(16, extern const uint8_t, vp9_cat6_prob[14]);
60
61 #define EOB_MODEL_TOKEN 3
62 extern const vp9_tree_index vp9_coefmodel_tree[];
63
64 typedef struct {
65 const vp9_tree_index *tree;
66 const vp9_prob *prob;
67 int len;
68 int base_val;
69 } vp9_extra_bit;
70
71 // indexed by token value
72 extern const vp9_extra_bit vp9_extra_bits[ENTROPY_TOKENS];
73
74 #define DCT_MAX_VALUE 16384
75
76 /* Coefficients are predicted via a 3-dimensional probability table. */
77
78 #define REF_TYPES 2 // intra=0, inter=1
79
80 /* Middle dimension reflects the coefficient position within the transform. */
81 #define COEF_BANDS 6
82
83 /* Inside dimension is measure of nearby complexity, that reflects the energy
84 of nearby coefficients are nonzero. For the first coefficient (DC, unless
85 block type is 0), we look at the (already encoded) blocks above and to the
86 left of the current block. The context index is then the number (0,1,or 2)
87 of these blocks having nonzero coefficients.
88 After decoding a coefficient, the measure is determined by the size of the
89 most recently decoded coefficient.
90 Note that the intuitive meaning of this measure changes as coefficients
91 are decoded, e.g., prior to the first token, a zero means that my neighbors
92 are empty while, after the first token, because of the use of end-of-block,
93 a zero means we just decoded a zero and hence guarantees that a non-zero
94 coefficient will appear later in this block. However, this shift
95 in meaning is perfectly OK because our context depends also on the
96 coefficient band (and since zigzag positions 0, 1, and 2 are in
97 distinct bands). */
98
99 #define COEFF_CONTEXTS 6
100 #define BAND_COEFF_CONTEXTS(band) ((band) == 0 ? 3 : COEFF_CONTEXTS)
101
102 // #define ENTROPY_STATS
103
104 typedef unsigned int vp9_coeff_count[REF_TYPES][COEF_BANDS][COEFF_CONTEXTS]
105 [ENTROPY_TOKENS];
106 typedef unsigned int vp9_coeff_stats[REF_TYPES][COEF_BANDS][COEFF_CONTEXTS]
107 [ENTROPY_NODES][2];
108
109 #define SUBEXP_PARAM 4 /* Subexponential code parameter */
110 #define MODULUS_PARAM 13 /* Modulus parameter */
111
112 struct VP9Common;
113 void vp9_default_coef_probs(struct VP9Common *cm);
114 void vp9_adapt_coef_probs(struct VP9Common *cm);
115
reset_skip_context(MACROBLOCKD * xd,BLOCK_SIZE bsize)116 static INLINE void reset_skip_context(MACROBLOCKD *xd, BLOCK_SIZE bsize) {
117 int i;
118 for (i = 0; i < MAX_MB_PLANE; i++) {
119 struct macroblockd_plane *const pd = &xd->plane[i];
120 const BLOCK_SIZE plane_bsize = get_plane_block_size(bsize, pd);
121 vpx_memset(pd->above_context, 0, sizeof(ENTROPY_CONTEXT) *
122 num_4x4_blocks_wide_lookup[plane_bsize]);
123 vpx_memset(pd->left_context, 0, sizeof(ENTROPY_CONTEXT) *
124 num_4x4_blocks_high_lookup[plane_bsize]);
125 }
126 }
127
128 // This is the index in the scan order beyond which all coefficients for
129 // 8x8 transform and above are in the top band.
130 // This macro is currently unused but may be used by certain implementations
131 #define MAXBAND_INDEX 21
132
133 DECLARE_ALIGNED(16, extern const uint8_t, vp9_coefband_trans_8x8plus[1024]);
134 DECLARE_ALIGNED(16, extern const uint8_t, vp9_coefband_trans_4x4[16]);
135
get_band_translate(TX_SIZE tx_size)136 static INLINE const uint8_t *get_band_translate(TX_SIZE tx_size) {
137 return tx_size == TX_4X4 ? vp9_coefband_trans_4x4
138 : vp9_coefband_trans_8x8plus;
139 }
140
141 // 128 lists of probabilities are stored for the following ONE node probs:
142 // 1, 3, 5, 7, ..., 253, 255
143 // In between probabilities are interpolated linearly
144
145 #define COEFF_PROB_MODELS 256
146
147 #define UNCONSTRAINED_NODES 3
148
149 #define PIVOT_NODE 2 // which node is pivot
150
151 #define MODEL_NODES (ENTROPY_NODES - UNCONSTRAINED_NODES)
152 extern const vp9_prob vp9_pareto8_full[COEFF_PROB_MODELS][MODEL_NODES];
153
154 typedef vp9_prob vp9_coeff_probs_model[REF_TYPES][COEF_BANDS]
155 [COEFF_CONTEXTS][UNCONSTRAINED_NODES];
156
157 typedef unsigned int vp9_coeff_count_model[REF_TYPES][COEF_BANDS]
158 [COEFF_CONTEXTS]
159 [UNCONSTRAINED_NODES + 1];
160
161 void vp9_model_to_full_probs(const vp9_prob *model, vp9_prob *full);
162
get_entropy_context(TX_SIZE tx_size,const ENTROPY_CONTEXT * a,const ENTROPY_CONTEXT * l)163 static INLINE int get_entropy_context(TX_SIZE tx_size, const ENTROPY_CONTEXT *a,
164 const ENTROPY_CONTEXT *l) {
165 ENTROPY_CONTEXT above_ec = 0, left_ec = 0;
166
167 switch (tx_size) {
168 case TX_4X4:
169 above_ec = a[0] != 0;
170 left_ec = l[0] != 0;
171 break;
172 case TX_8X8:
173 above_ec = !!*(const uint16_t *)a;
174 left_ec = !!*(const uint16_t *)l;
175 break;
176 case TX_16X16:
177 above_ec = !!*(const uint32_t *)a;
178 left_ec = !!*(const uint32_t *)l;
179 break;
180 case TX_32X32:
181 above_ec = !!*(const uint64_t *)a;
182 left_ec = !!*(const uint64_t *)l;
183 break;
184 default:
185 assert(0 && "Invalid transform size.");
186 break;
187 }
188
189 return combine_entropy_contexts(above_ec, left_ec);
190 }
191
get_scan(const MACROBLOCKD * xd,TX_SIZE tx_size,PLANE_TYPE type,int block_idx)192 static INLINE const scan_order *get_scan(const MACROBLOCKD *xd, TX_SIZE tx_size,
193 PLANE_TYPE type, int block_idx) {
194 const MODE_INFO *const mi = xd->mi[0];
195
196 if (is_inter_block(&mi->mbmi) || type != PLANE_TYPE_Y || xd->lossless) {
197 return &vp9_default_scan_orders[tx_size];
198 } else {
199 const PREDICTION_MODE mode = get_y_mode(mi, block_idx);
200 return &vp9_scan_orders[tx_size][intra_mode_to_tx_type_lookup[mode]];
201 }
202 }
203
204 #ifdef __cplusplus
205 } // extern "C"
206 #endif
207
208 #endif // VP9_COMMON_VP9_ENTROPY_H_
209