blob: cce6bdae5f93af7c7c899a5e98ad1cf518da8482 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
|
// SPDX-License-Identifier: 0BSD
///////////////////////////////////////////////////////////////////////////////
//
/// \file price.h
/// \brief Probability price calculation
//
// Author: Igor Pavlov
//
///////////////////////////////////////////////////////////////////////////////
#ifndef LZMA_PRICE_H
#define LZMA_PRICE_H
#define RC_MOVE_REDUCING_BITS 4
#define RC_BIT_PRICE_SHIFT_BITS 4
#define RC_PRICE_TABLE_SIZE (RC_BIT_MODEL_TOTAL >> RC_MOVE_REDUCING_BITS)
#define RC_INFINITY_PRICE (UINT32_C(1) << 30)
/// Lookup table for the inline functions defined in this file.
lzma_attr_visibility_hidden
extern const uint8_t lzma_rc_prices[RC_PRICE_TABLE_SIZE];
static inline uint32_t
rc_bit_price(const probability prob, const uint32_t bit)
{
return lzma_rc_prices[(prob ^ ((UINT32_C(0) - bit)
& (RC_BIT_MODEL_TOTAL - 1))) >> RC_MOVE_REDUCING_BITS];
}
static inline uint32_t
rc_bit_0_price(const probability prob)
{
return lzma_rc_prices[prob >> RC_MOVE_REDUCING_BITS];
}
static inline uint32_t
rc_bit_1_price(const probability prob)
{
return lzma_rc_prices[(prob ^ (RC_BIT_MODEL_TOTAL - 1))
>> RC_MOVE_REDUCING_BITS];
}
static inline uint32_t
rc_bittree_price(const probability *const probs,
const uint32_t bit_levels, uint32_t symbol)
{
uint32_t price = 0;
symbol += UINT32_C(1) << bit_levels;
do {
const uint32_t bit = symbol & 1;
symbol >>= 1;
price += rc_bit_price(probs[symbol], bit);
} while (symbol != 1);
return price;
}
static inline uint32_t
rc_bittree_reverse_price(const probability *const probs,
uint32_t bit_levels, uint32_t symbol)
{
uint32_t price = 0;
uint32_t model_index = 1;
do {
const uint32_t bit = symbol & 1;
symbol >>= 1;
price += rc_bit_price(probs[model_index], bit);
model_index = (model_index << 1) + bit;
} while (--bit_levels != 0);
return price;
}
static inline uint32_t
rc_direct_price(const uint32_t bits)
{
return bits << RC_BIT_PRICE_SHIFT_BITS;
}
#endif
|
