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
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
#include "common.h"
#include "bitstream.h"
#include "threading.h"
using namespace X265_NS;
#if defined(_MSC_VER)
#pragma warning(disable: 4244)
#endif
#define MIN_FIFO_SIZE 1000
Bitstream::Bitstream()
{
m_fifo = X265_MALLOC(uint8_t, MIN_FIFO_SIZE);
m_byteAlloc = MIN_FIFO_SIZE;
resetBits();
}
void Bitstream::push_back(uint8_t val)
{
if (!m_fifo)
return;
if (m_byteOccupancy >= m_byteAlloc)
{
/** reallocate buffer with doubled size */
uint8_t *temp = X265_MALLOC(uint8_t, m_byteAlloc * 2);
if (temp)
{
memcpy(temp, m_fifo, m_byteOccupancy);
X265_FREE(m_fifo);
m_fifo = temp;
m_byteAlloc *= 2;
}
else
{
x265_log(NULL, X265_LOG_ERROR, "Unable to realloc bitstream buffer");
return;
}
}
m_fifo[m_byteOccupancy++] = val;
}
void Bitstream::write(uint32_t val, uint32_t numBits)
{
X265_CHECK(numBits <= 32, "numBits out of range\n");
X265_CHECK(numBits == 32 || ((val & (~0u << numBits)) == 0), "numBits & val out of range\n");
uint32_t totalPartialBits = m_partialByteBits + numBits;
uint32_t nextPartialBits = totalPartialBits & 7;
uint8_t nextHeldByte = val << (8 - nextPartialBits);
uint32_t writeBytes = totalPartialBits >> 3;
if (writeBytes)
{
/* topword aligns m_partialByte with the msb of val */
uint32_t topword = (numBits - nextPartialBits) & ~7;
#if USING_FTRAPV
uint32_t write_bits = (topword < 32 ? m_partialByte << topword : 0) | (val >> nextPartialBits);
#else
uint32_t write_bits = (m_partialByte << topword) | (val >> nextPartialBits);
#endif
switch (writeBytes)
{
case 4: push_back(write_bits >> 24); // fall-through
case 3: push_back(write_bits >> 16); // fall-through
case 2: push_back(write_bits >> 8); // fall-through
case 1: push_back(write_bits);
}
m_partialByte = nextHeldByte;
m_partialByteBits = nextPartialBits;
}
else
{
m_partialByte |= nextHeldByte;
m_partialByteBits = nextPartialBits;
}
}
void Bitstream::writeByte(uint32_t val)
{
// Only CABAC will call writeByte, the fifo must be byte aligned
X265_CHECK(!m_partialByteBits, "expecting m_partialByteBits = 0\n");
push_back(val);
}
void Bitstream::writeAlignOne()
{
uint32_t numBits = (8 - m_partialByteBits) & 0x7;
write((1 << numBits) - 1, numBits);
}
void Bitstream::writeAlignZero()
{
if (m_partialByteBits)
{
push_back(m_partialByte);
m_partialByte = 0;
m_partialByteBits = 0;
}
}
void Bitstream::writeByteAlignment()
{
write(1, 1);
writeAlignZero();
}
void SyntaxElementWriter::writeUvlc(uint32_t code)
{
++code;
X265_CHECK(code, "writing -1 code, will cause infinite loop\n");
unsigned long idx;
CLZ(idx, code);
uint32_t length = (uint32_t)idx * 2 + 1;
// Take care of cases where length > 32
m_bitIf->write(0, length >> 1);
m_bitIf->write(code, (length + 1) >> 1);
}
|
