1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libvpx/vp9/common/vp9_entropy.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,204 @@
1.4 +/*
1.5 + * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license
1.8 + * that can be found in the LICENSE file in the root of the source
1.9 + * tree. An additional intellectual property rights grant can be found
1.10 + * in the file PATENTS. All contributing project authors may
1.11 + * be found in the AUTHORS file in the root of the source tree.
1.12 + */
1.13 +
1.14 +#ifndef VP9_COMMON_VP9_ENTROPY_H_
1.15 +#define VP9_COMMON_VP9_ENTROPY_H_
1.16 +
1.17 +#include "vpx/vpx_integer.h"
1.18 +
1.19 +#include "vp9/common/vp9_blockd.h"
1.20 +#include "vp9/common/vp9_common.h"
1.21 +#include "vp9/common/vp9_scan.h"
1.22 +#include "vp9/common/vp9_treecoder.h"
1.23 +
1.24 +#define DIFF_UPDATE_PROB 252
1.25 +
1.26 +/* Coefficient token alphabet */
1.27 +
1.28 +#define ZERO_TOKEN 0 /* 0 Extra Bits 0+0 */
1.29 +#define ONE_TOKEN 1 /* 1 Extra Bits 0+1 */
1.30 +#define TWO_TOKEN 2 /* 2 Extra Bits 0+1 */
1.31 +#define THREE_TOKEN 3 /* 3 Extra Bits 0+1 */
1.32 +#define FOUR_TOKEN 4 /* 4 Extra Bits 0+1 */
1.33 +#define DCT_VAL_CATEGORY1 5 /* 5-6 Extra Bits 1+1 */
1.34 +#define DCT_VAL_CATEGORY2 6 /* 7-10 Extra Bits 2+1 */
1.35 +#define DCT_VAL_CATEGORY3 7 /* 11-18 Extra Bits 3+1 */
1.36 +#define DCT_VAL_CATEGORY4 8 /* 19-34 Extra Bits 4+1 */
1.37 +#define DCT_VAL_CATEGORY5 9 /* 35-66 Extra Bits 5+1 */
1.38 +#define DCT_VAL_CATEGORY6 10 /* 67+ Extra Bits 14+1 */
1.39 +#define DCT_EOB_TOKEN 11 /* EOB Extra Bits 0+0 */
1.40 +#define MAX_ENTROPY_TOKENS 12
1.41 +#define ENTROPY_NODES 11
1.42 +#define EOSB_TOKEN 127 /* Not signalled, encoder only */
1.43 +
1.44 +#define INTER_MODE_CONTEXTS 7
1.45 +
1.46 +extern DECLARE_ALIGNED(16, const uint8_t,
1.47 + vp9_pt_energy_class[MAX_ENTROPY_TOKENS]);
1.48 +
1.49 +extern const vp9_tree_index vp9_coef_tree[TREE_SIZE(MAX_ENTROPY_TOKENS)];
1.50 +
1.51 +#define DCT_EOB_MODEL_TOKEN 3 /* EOB Extra Bits 0+0 */
1.52 +extern const vp9_tree_index vp9_coefmodel_tree[];
1.53 +
1.54 +extern struct vp9_token vp9_coef_encodings[MAX_ENTROPY_TOKENS];
1.55 +
1.56 +typedef struct {
1.57 + const vp9_tree_index *tree;
1.58 + const vp9_prob *prob;
1.59 + int len;
1.60 + int base_val;
1.61 +} vp9_extra_bit;
1.62 +
1.63 +// indexed by token value
1.64 +extern const vp9_extra_bit vp9_extra_bits[MAX_ENTROPY_TOKENS];
1.65 +
1.66 +#define MAX_PROB 255
1.67 +#define DCT_MAX_VALUE 16384
1.68 +
1.69 +/* Coefficients are predicted via a 3-dimensional probability table. */
1.70 +
1.71 +/* Outside dimension. 0 = Y with DC, 1 = UV */
1.72 +#define BLOCK_TYPES 2
1.73 +#define REF_TYPES 2 // intra=0, inter=1
1.74 +
1.75 +/* Middle dimension reflects the coefficient position within the transform. */
1.76 +#define COEF_BANDS 6
1.77 +
1.78 +/* Inside dimension is measure of nearby complexity, that reflects the energy
1.79 + of nearby coefficients are nonzero. For the first coefficient (DC, unless
1.80 + block type is 0), we look at the (already encoded) blocks above and to the
1.81 + left of the current block. The context index is then the number (0,1,or 2)
1.82 + of these blocks having nonzero coefficients.
1.83 + After decoding a coefficient, the measure is determined by the size of the
1.84 + most recently decoded coefficient.
1.85 + Note that the intuitive meaning of this measure changes as coefficients
1.86 + are decoded, e.g., prior to the first token, a zero means that my neighbors
1.87 + are empty while, after the first token, because of the use of end-of-block,
1.88 + a zero means we just decoded a zero and hence guarantees that a non-zero
1.89 + coefficient will appear later in this block. However, this shift
1.90 + in meaning is perfectly OK because our context depends also on the
1.91 + coefficient band (and since zigzag positions 0, 1, and 2 are in
1.92 + distinct bands). */
1.93 +
1.94 +#define PREV_COEF_CONTEXTS 6
1.95 +
1.96 +// #define ENTROPY_STATS
1.97 +
1.98 +typedef unsigned int vp9_coeff_count[REF_TYPES][COEF_BANDS][PREV_COEF_CONTEXTS]
1.99 + [MAX_ENTROPY_TOKENS];
1.100 +typedef unsigned int vp9_coeff_stats[REF_TYPES][COEF_BANDS][PREV_COEF_CONTEXTS]
1.101 + [ENTROPY_NODES][2];
1.102 +
1.103 +#define SUBEXP_PARAM 4 /* Subexponential code parameter */
1.104 +#define MODULUS_PARAM 13 /* Modulus parameter */
1.105 +
1.106 +struct VP9Common;
1.107 +void vp9_default_coef_probs(struct VP9Common *cm);
1.108 +
1.109 +void vp9_coef_tree_initialize();
1.110 +void vp9_adapt_coef_probs(struct VP9Common *cm);
1.111 +
1.112 +static INLINE void reset_skip_context(MACROBLOCKD *xd, BLOCK_SIZE bsize) {
1.113 + int i;
1.114 + for (i = 0; i < MAX_MB_PLANE; i++) {
1.115 + struct macroblockd_plane *const pd = &xd->plane[i];
1.116 + const BLOCK_SIZE plane_bsize = get_plane_block_size(bsize, pd);
1.117 + vpx_memset(pd->above_context, 0, sizeof(ENTROPY_CONTEXT) *
1.118 + num_4x4_blocks_wide_lookup[plane_bsize]);
1.119 + vpx_memset(pd->left_context, 0, sizeof(ENTROPY_CONTEXT) *
1.120 + num_4x4_blocks_high_lookup[plane_bsize]);
1.121 + }
1.122 +}
1.123 +
1.124 +// This is the index in the scan order beyond which all coefficients for
1.125 +// 8x8 transform and above are in the top band.
1.126 +// This macro is currently unused but may be used by certain implementations
1.127 +#define MAXBAND_INDEX 21
1.128 +
1.129 +extern const uint8_t vp9_coefband_trans_8x8plus[1024];
1.130 +extern const uint8_t vp9_coefband_trans_4x4[16];
1.131 +
1.132 +static const uint8_t *get_band_translate(TX_SIZE tx_size) {
1.133 + return tx_size == TX_4X4 ? vp9_coefband_trans_4x4
1.134 + : vp9_coefband_trans_8x8plus;
1.135 +}
1.136 +
1.137 +// 128 lists of probabilities are stored for the following ONE node probs:
1.138 +// 1, 3, 5, 7, ..., 253, 255
1.139 +// In between probabilities are interpolated linearly
1.140 +
1.141 +#define COEFPROB_MODELS 128
1.142 +
1.143 +#define UNCONSTRAINED_NODES 3
1.144 +
1.145 +#define PIVOT_NODE 2 // which node is pivot
1.146 +
1.147 +typedef vp9_prob vp9_coeff_probs_model[REF_TYPES][COEF_BANDS]
1.148 + [PREV_COEF_CONTEXTS]
1.149 + [UNCONSTRAINED_NODES];
1.150 +
1.151 +typedef unsigned int vp9_coeff_count_model[REF_TYPES][COEF_BANDS]
1.152 + [PREV_COEF_CONTEXTS]
1.153 + [UNCONSTRAINED_NODES + 1];
1.154 +
1.155 +void vp9_model_to_full_probs(const vp9_prob *model, vp9_prob *full);
1.156 +
1.157 +static int get_entropy_context(TX_SIZE tx_size, const ENTROPY_CONTEXT *a,
1.158 + const ENTROPY_CONTEXT *l) {
1.159 + ENTROPY_CONTEXT above_ec = 0, left_ec = 0;
1.160 +
1.161 + switch (tx_size) {
1.162 + case TX_4X4:
1.163 + above_ec = a[0] != 0;
1.164 + left_ec = l[0] != 0;
1.165 + break;
1.166 + case TX_8X8:
1.167 + above_ec = !!*(const uint16_t *)a;
1.168 + left_ec = !!*(const uint16_t *)l;
1.169 + break;
1.170 + case TX_16X16:
1.171 + above_ec = !!*(const uint32_t *)a;
1.172 + left_ec = !!*(const uint32_t *)l;
1.173 + break;
1.174 + case TX_32X32:
1.175 + above_ec = !!*(const uint64_t *)a;
1.176 + left_ec = !!*(const uint64_t *)l;
1.177 + break;
1.178 + default:
1.179 + assert(!"Invalid transform size.");
1.180 + }
1.181 +
1.182 + return combine_entropy_contexts(above_ec, left_ec);
1.183 +}
1.184 +
1.185 +static void get_scan(const MACROBLOCKD *xd, TX_SIZE tx_size,
1.186 + PLANE_TYPE type, int block_idx,
1.187 + const int16_t **scan, const int16_t **scan_nb) {
1.188 + switch (tx_size) {
1.189 + case TX_4X4:
1.190 + get_scan_nb_4x4(get_tx_type_4x4(type, xd, block_idx), scan, scan_nb);
1.191 + break;
1.192 + case TX_8X8:
1.193 + get_scan_nb_8x8(get_tx_type_8x8(type, xd), scan, scan_nb);
1.194 + break;
1.195 + case TX_16X16:
1.196 + get_scan_nb_16x16(get_tx_type_16x16(type, xd), scan, scan_nb);
1.197 + break;
1.198 + case TX_32X32:
1.199 + *scan = vp9_default_scan_32x32;
1.200 + *scan_nb = vp9_default_scan_32x32_neighbors;
1.201 + break;
1.202 + default:
1.203 + assert(!"Invalid transform size.");
1.204 + }
1.205 +}
1.206 +
1.207 +#endif // VP9_COMMON_VP9_ENTROPY_H_
