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
12#ifndef VP8_COMMON_ENTROPY_H_
13#define VP8_COMMON_ENTROPY_H_
14
15#include "treecoder.h"
16#include "blockd.h"
17
18#ifdef __cplusplus
19extern "C" {
20#endif
21
22/* Coefficient token alphabet */
23
24#define ZERO_TOKEN              0       /* 0         Extra Bits 0+0 */
25#define ONE_TOKEN               1       /* 1         Extra Bits 0+1 */
26#define TWO_TOKEN               2       /* 2         Extra Bits 0+1 */
27#define THREE_TOKEN             3       /* 3         Extra Bits 0+1 */
28#define FOUR_TOKEN              4       /* 4         Extra Bits 0+1 */
29#define DCT_VAL_CATEGORY1       5       /* 5-6       Extra Bits 1+1 */
30#define DCT_VAL_CATEGORY2       6       /* 7-10      Extra Bits 2+1 */
31#define DCT_VAL_CATEGORY3       7       /* 11-18     Extra Bits 3+1 */
32#define DCT_VAL_CATEGORY4       8       /* 19-34     Extra Bits 4+1 */
33#define DCT_VAL_CATEGORY5       9       /* 35-66     Extra Bits 5+1 */
34#define DCT_VAL_CATEGORY6       10      /* 67+       Extra Bits 11+1 */
35#define DCT_EOB_TOKEN           11      /* EOB       Extra Bits 0+0 */
36
37#define MAX_ENTROPY_TOKENS 12
38#define ENTROPY_NODES 11
39
40extern const vp8_tree_index vp8_coef_tree[];
41
42extern const struct vp8_token_struct vp8_coef_encodings[MAX_ENTROPY_TOKENS];
43
44typedef struct
45{
46    vp8_tree_p tree;
47    const vp8_prob *prob;
48    int Len;
49    int base_val;
50} vp8_extra_bit_struct;
51
52extern const vp8_extra_bit_struct vp8_extra_bits[12];    /* indexed by token value */
53
54#define PROB_UPDATE_BASELINE_COST   7
55
56#define MAX_PROB                255
57#define DCT_MAX_VALUE           2048
58
59
60/* Coefficients are predicted via a 3-dimensional probability table. */
61
62/* Outside dimension.  0 = Y no DC, 1 = Y2, 2 = UV, 3 = Y with DC */
63
64#define BLOCK_TYPES 4
65
66/* Middle dimension is a coarsening of the coefficient's
67   position within the 4x4 DCT. */
68
69#define COEF_BANDS 8
70extern DECLARE_ALIGNED(16, const unsigned char, vp8_coef_bands[16]);
71
72/* Inside dimension is 3-valued measure of nearby complexity, that is,
73   the extent to which nearby coefficients are nonzero.  For the first
74   coefficient (DC, unless block type is 0), we look at the (already encoded)
75   blocks above and to the left of the current block.  The context index is
76   then the number (0,1,or 2) of these blocks having nonzero coefficients.
77   After decoding a coefficient, the measure is roughly the size of the
78   most recently decoded coefficient (0 for 0, 1 for 1, 2 for >1).
79   Note that the intuitive meaning of this measure changes as coefficients
80   are decoded, e.g., prior to the first token, a zero means that my neighbors
81   are empty while, after the first token, because of the use of end-of-block,
82   a zero means we just decoded a zero and hence guarantees that a non-zero
83   coefficient will appear later in this block.  However, this shift
84   in meaning is perfectly OK because our context depends also on the
85   coefficient band (and since zigzag positions 0, 1, and 2 are in
86   distinct bands). */
87
88/*# define DC_TOKEN_CONTEXTS        3*/ /* 00, 0!0, !0!0 */
89#   define PREV_COEF_CONTEXTS       3
90
91extern DECLARE_ALIGNED(16, const unsigned char, vp8_prev_token_class[MAX_ENTROPY_TOKENS]);
92
93extern const vp8_prob vp8_coef_update_probs [BLOCK_TYPES] [COEF_BANDS] [PREV_COEF_CONTEXTS] [ENTROPY_NODES];
94
95
96struct VP8Common;
97void vp8_default_coef_probs(struct VP8Common *);
98
99extern DECLARE_ALIGNED(16, const int, vp8_default_zig_zag1d[16]);
100extern DECLARE_ALIGNED(16, const short, vp8_default_inv_zig_zag[16]);
101extern DECLARE_ALIGNED(16, const short, vp8_default_zig_zag_mask[16]);
102extern const int vp8_mb_feature_data_bits[MB_LVL_MAX];
103
104void vp8_coef_tree_initialize(void);
105#ifdef __cplusplus
106}  // extern "C"
107#endif
108
109#endif  // VP8_COMMON_ENTROPY_H_
110