2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
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.
11 #ifndef VP9_COMMON_VP9_ENTROPY_H_
12 #define VP9_COMMON_VP9_ENTROPY_H_
14 #include "vpx/vpx_integer.h"
16 #include "vp9/common/vp9_blockd.h"
17 #include "vp9/common/vp9_common.h"
18 #include "vp9/common/vp9_scan.h"
19 #include "vp9/common/vp9_entropymode.h"
25 #define DIFF_UPDATE_PROB 252
27 // Coefficient token alphabet
28 #define ZERO_TOKEN 0 // 0 Extra Bits 0+0
29 #define ONE_TOKEN 1 // 1 Extra Bits 0+1
30 #define TWO_TOKEN 2 // 2 Extra Bits 0+1
31 #define THREE_TOKEN 3 // 3 Extra Bits 0+1
32 #define FOUR_TOKEN 4 // 4 Extra Bits 0+1
33 #define CATEGORY1_TOKEN 5 // 5-6 Extra Bits 1+1
34 #define CATEGORY2_TOKEN 6 // 7-10 Extra Bits 2+1
35 #define CATEGORY3_TOKEN 7 // 11-18 Extra Bits 3+1
36 #define CATEGORY4_TOKEN 8 // 19-34 Extra Bits 4+1
37 #define CATEGORY5_TOKEN 9 // 35-66 Extra Bits 5+1
38 #define CATEGORY6_TOKEN 10 // 67+ Extra Bits 14+1
39 #define EOB_TOKEN 11 // EOB Extra Bits 0+0
41 #define ENTROPY_TOKENS 12
43 #define ENTROPY_NODES 11
45 extern DECLARE_ALIGNED(16, const uint8_t, vp9_pt_energy_class[ENTROPY_TOKENS]);
47 #define EOB_MODEL_TOKEN 3
48 extern const vp9_tree_index vp9_coefmodel_tree[];
51 const vp9_tree_index *tree;
57 // indexed by token value
58 extern const vp9_extra_bit vp9_extra_bits[ENTROPY_TOKENS];
60 #define DCT_MAX_VALUE 16384
62 /* Coefficients are predicted via a 3-dimensional probability table. */
64 #define REF_TYPES 2 // intra=0, inter=1
66 /* Middle dimension reflects the coefficient position within the transform. */
69 /* Inside dimension is measure of nearby complexity, that reflects the energy
70 of nearby coefficients are nonzero. For the first coefficient (DC, unless
71 block type is 0), we look at the (already encoded) blocks above and to the
72 left of the current block. The context index is then the number (0,1,or 2)
73 of these blocks having nonzero coefficients.
74 After decoding a coefficient, the measure is determined by the size of the
75 most recently decoded coefficient.
76 Note that the intuitive meaning of this measure changes as coefficients
77 are decoded, e.g., prior to the first token, a zero means that my neighbors
78 are empty while, after the first token, because of the use of end-of-block,
79 a zero means we just decoded a zero and hence guarantees that a non-zero
80 coefficient will appear later in this block. However, this shift
81 in meaning is perfectly OK because our context depends also on the
82 coefficient band (and since zigzag positions 0, 1, and 2 are in
85 #define COEFF_CONTEXTS 6
86 #define BAND_COEFF_CONTEXTS(band) ((band) == 0 ? 3 : COEFF_CONTEXTS)
88 // #define ENTROPY_STATS
90 typedef unsigned int vp9_coeff_count[REF_TYPES][COEF_BANDS][COEFF_CONTEXTS]
92 typedef unsigned int vp9_coeff_stats[REF_TYPES][COEF_BANDS][COEFF_CONTEXTS]
95 #define SUBEXP_PARAM 4 /* Subexponential code parameter */
96 #define MODULUS_PARAM 13 /* Modulus parameter */
99 void vp9_default_coef_probs(struct VP9Common *cm);
100 void vp9_adapt_coef_probs(struct VP9Common *cm);
102 static INLINE void reset_skip_context(MACROBLOCKD *xd, BLOCK_SIZE bsize) {
104 for (i = 0; i < MAX_MB_PLANE; i++) {
105 struct macroblockd_plane *const pd = &xd->plane[i];
106 const BLOCK_SIZE plane_bsize = get_plane_block_size(bsize, pd);
107 vpx_memset(pd->above_context, 0, sizeof(ENTROPY_CONTEXT) *
108 num_4x4_blocks_wide_lookup[plane_bsize]);
109 vpx_memset(pd->left_context, 0, sizeof(ENTROPY_CONTEXT) *
110 num_4x4_blocks_high_lookup[plane_bsize]);
114 // This is the index in the scan order beyond which all coefficients for
115 // 8x8 transform and above are in the top band.
116 // This macro is currently unused but may be used by certain implementations
117 #define MAXBAND_INDEX 21
119 extern DECLARE_ALIGNED(16, const uint8_t, vp9_coefband_trans_8x8plus[1024]);
120 extern DECLARE_ALIGNED(16, const uint8_t, vp9_coefband_trans_4x4[16]);
122 static INLINE const uint8_t *get_band_translate(TX_SIZE tx_size) {
123 return tx_size == TX_4X4 ? vp9_coefband_trans_4x4
124 : vp9_coefband_trans_8x8plus;
127 // 128 lists of probabilities are stored for the following ONE node probs:
128 // 1, 3, 5, 7, ..., 253, 255
129 // In between probabilities are interpolated linearly
131 #define COEFF_PROB_MODELS 256
133 #define UNCONSTRAINED_NODES 3
135 #define PIVOT_NODE 2 // which node is pivot
137 #define MODEL_NODES (ENTROPY_NODES - UNCONSTRAINED_NODES)
138 extern const vp9_prob vp9_pareto8_full[COEFF_PROB_MODELS][MODEL_NODES];
140 typedef vp9_prob vp9_coeff_probs_model[REF_TYPES][COEF_BANDS]
141 [COEFF_CONTEXTS][UNCONSTRAINED_NODES];
143 typedef unsigned int vp9_coeff_count_model[REF_TYPES][COEF_BANDS]
145 [UNCONSTRAINED_NODES + 1];
147 void vp9_model_to_full_probs(const vp9_prob *model, vp9_prob *full);
149 static INLINE int get_entropy_context(TX_SIZE tx_size, const ENTROPY_CONTEXT *a,
150 const ENTROPY_CONTEXT *l) {
151 ENTROPY_CONTEXT above_ec = 0, left_ec = 0;
155 above_ec = a[0] != 0;
159 above_ec = !!*(const uint16_t *)a;
160 left_ec = !!*(const uint16_t *)l;
163 above_ec = !!*(const uint32_t *)a;
164 left_ec = !!*(const uint32_t *)l;
167 above_ec = !!*(const uint64_t *)a;
168 left_ec = !!*(const uint64_t *)l;
171 assert(0 && "Invalid transform size.");
174 return combine_entropy_contexts(above_ec, left_ec);
177 static const INLINE scan_order *get_scan(const MACROBLOCKD *xd, TX_SIZE tx_size,
178 PLANE_TYPE type, int block_idx) {
179 const MODE_INFO *const mi = xd->mi_8x8[0];
180 const MB_MODE_INFO *const mbmi = &mi->mbmi;
182 if (is_inter_block(mbmi) || type != PLANE_TYPE_Y || xd->lossless) {
183 return &vp9_default_scan_orders[tx_size];
185 const MB_PREDICTION_MODE mode =
186 mbmi->sb_type < BLOCK_8X8 ? mi->bmi[block_idx].as_mode : mbmi->mode;
187 return &vp9_scan_orders[tx_size][mode2txfm_map[mode]];
195 #endif // VP9_COMMON_VP9_ENTROPY_H_