blob: 46cdda54cb98b154e363e1452fd12bfa61a0d5f5 (
plain)
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
|
/* Copyright 2013 Google Inc. All Rights Reserved.
Distributed under MIT license.
See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
*/
/* Functions for clustering similar histograms together. */
#include "./cluster.h"
#include "../common/types.h"
#include "./bit_cost.h" /* BrotliPopulationCost */
#include "./fast_log.h"
#include "./histogram.h"
#include "./memory.h"
#include "./port.h"
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif
static BROTLI_INLINE BROTLI_BOOL HistogramPairIsLess(
const HistogramPair* p1, const HistogramPair* p2) {
if (p1->cost_diff != p2->cost_diff) {
return TO_BROTLI_BOOL(p1->cost_diff > p2->cost_diff);
}
return TO_BROTLI_BOOL((p1->idx2 - p1->idx1) > (p2->idx2 - p2->idx1));
}
/* Returns entropy reduction of the context map when we combine two clusters. */
static BROTLI_INLINE double ClusterCostDiff(size_t size_a, size_t size_b) {
size_t size_c = size_a + size_b;
return (double)size_a * FastLog2(size_a) +
(double)size_b * FastLog2(size_b) -
(double)size_c * FastLog2(size_c);
}
#define CODE(X) X
#define FN(X) X ## Literal
#include "./cluster_inc.h" /* NOLINT(build/include) */
#undef FN
#define FN(X) X ## Command
#include "./cluster_inc.h" /* NOLINT(build/include) */
#undef FN
#define FN(X) X ## Distance
#include "./cluster_inc.h" /* NOLINT(build/include) */
#undef FN
#undef CODE
#if defined(__cplusplus) || defined(c_plusplus)
} /* extern "C" */
#endif
|
