TUT HEVC Encoder
kvz_math.h
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1#ifndef MATH_H_
2#define MATH_H_
3/*****************************************************************************
4 * This file is part of Kvazaar HEVC encoder.
5 *
6 * Copyright (c) 2021, Tampere University, ITU/ISO/IEC, project contributors
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34
40#include "global.h" // IWYU pragma: keep
41
42
43static INLINE unsigned kvz_math_floor_log2(unsigned value)
44{
45 assert(value > 0);
46
47 unsigned result = 0;
48
49 for (int i = 4; i >= 0; --i) {
50 unsigned bits = 1ull << i;
51 unsigned shift = value >= (1 << bits) ? bits : 0;
52 result += shift;
53 value >>= shift;
54 }
55
56 return result;
57}
58
59static INLINE unsigned kvz_math_ceil_log2(unsigned value)
60{
61 assert(value > 0);
62
63 // The ceil_log2 is just floor_log2 + 1, except for exact powers of 2.
64 return kvz_math_floor_log2(value) + ((value & (value - 1)) ? 1 : 0);
65}
66
67#endif //CHECKPOINT_H_
Header that is included in every other header.
#define INLINE
Definition: global.h:240
static unsigned kvz_math_floor_log2(unsigned value)
Definition: kvz_math.h:43
static unsigned kvz_math_ceil_log2(unsigned value)
Definition: kvz_math.h:59