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1 // Copyright 2017 The Chromium Authors. All rights reserved. | |
2 // Use of this source code is governed by a BSD-style license that can be | |
3 // found in the LICENSE file. | |
4 | |
5 #include "platform/audio/PushPullFIFO.h" | |
6 | |
7 #include "platform/audio/AudioUtilities.h" | |
8 #include "wtf/PtrUtil.h" | |
9 #include <memory> | |
10 | |
11 namespace blink { | |
12 | |
13 // Suppress the warning log if over/underflow happens more than 100 times. | |
14 const unsigned kMaxMessagesToLog = 100; | |
o1ka
2017/02/02 16:30:24
Put it into an unnamed namespace?
hongchan
2017/02/02 19:55:23
Done.
| |
15 | |
16 PushPullFIFO::PushPullFIFO(unsigned numberOfChannels, size_t fifoLength) | |
17 : m_fifoLength(fifoLength), | |
18 m_framesAvailable(0), | |
19 m_indexRead(0), | |
20 m_indexWrite(0), | |
21 m_overflowCount(0), | |
22 m_underflowCount(0) { | |
23 CHECK_LE(m_fifoLength, kMaxFIFOLength); | |
24 m_fifoBus = AudioBus::create(numberOfChannels, m_fifoLength); | |
25 } | |
26 | |
27 PushPullFIFO::~PushPullFIFO() {} | |
28 | |
29 // Push the data from |inputBus| to FIFO. The size of push is determined by | |
30 // the length of |inputBus|. | |
31 void PushPullFIFO::push(const AudioBus* inputBus) { | |
32 CHECK(inputBus); | |
33 CHECK_EQ(inputBus->length(), AudioUtilities::kRenderQuantumFrames); | |
34 SECURITY_CHECK(inputBus->length() <= m_fifoLength); | |
35 SECURITY_CHECK(m_indexWrite < m_fifoLength); | |
36 | |
37 const size_t inputBusLength = inputBus->length(); | |
38 const size_t remainder = m_fifoLength - m_indexWrite; | |
39 | |
40 for (unsigned i = 0; i < m_fifoBus->numberOfChannels(); ++i) { | |
41 float* fifoBusChannel = m_fifoBus->channel(i)->mutableData(); | |
42 const float* inputBusChannel = inputBus->channel(i)->data(); | |
43 if (remainder >= inputBusLength) { | |
44 // The remainder is big enough for the input data. | |
45 memcpy(fifoBusChannel + m_indexWrite, inputBusChannel, | |
46 inputBusLength * sizeof(*fifoBusChannel)); | |
47 } else { | |
48 // The input data overflows the remainder size. Wrap around the index. | |
49 memcpy(fifoBusChannel + m_indexWrite, inputBusChannel, | |
50 remainder * sizeof(*fifoBusChannel)); | |
51 memcpy(fifoBusChannel, inputBusChannel + remainder, | |
52 (inputBusLength - remainder) * sizeof(*fifoBusChannel)); | |
53 } | |
54 } | |
55 | |
56 // Update the write index; wrap it around if necessary. | |
57 m_indexWrite = (m_indexWrite + inputBusLength) % m_fifoLength; | |
58 | |
59 // In case of overflow, move the |indexRead| to the updated |indexWrite| to | |
60 // avoid reading overwritten frames by the next pull. | |
61 if (inputBusLength > m_fifoLength - m_framesAvailable) { | |
62 m_indexRead = m_indexWrite; | |
63 if (++m_overflowCount < kMaxMessagesToLog) { | |
64 DVLOG(1) << "PushPullFIFO: overflow while pushing (" | |
65 << "overflowCount=" << m_overflowCount | |
66 << ", availableFrames=" << m_framesAvailable | |
67 << ", inputFrames=" << inputBusLength | |
68 << ", fifoLength=" << m_fifoLength << ")"; | |
69 } | |
70 } | |
71 | |
72 // Update the number of frames available in FIFO. | |
73 m_framesAvailable = | |
74 std::min(m_framesAvailable + inputBusLength, m_fifoLength); | |
o1ka
2017/02/02 16:30:24
DCHECK that relations between m_indexRead, m_index
hongchan
2017/02/02 19:55:23
This doesn't seem to possible because of the heuri
o1ka
2017/02/03 10:41:17
How about DCHECK_EQ((m_indexRead + m_framesAvailab
hongchan
2017/02/03 17:20:11
Well, I thought you wanted the verification purely
| |
75 } | |
76 | |
77 // Pull the data out of FIFO to |outputBus|. If remaining frame in the FIFO | |
78 // is less than the frames to pull, provides remaining frame plus the silence. | |
79 void PushPullFIFO::pull(AudioBus* outputBus, size_t framesRequested) { | |
80 CHECK(outputBus); | |
81 SECURITY_CHECK(framesRequested <= outputBus->length()); | |
82 SECURITY_CHECK(framesRequested <= m_fifoLength); | |
83 SECURITY_CHECK(m_indexRead < m_fifoLength); | |
84 | |
85 const size_t remainder = m_fifoLength - m_indexRead; | |
86 const size_t framesToFill = std::min(m_framesAvailable, framesRequested); | |
87 | |
88 for (unsigned i = 0; i < m_fifoBus->numberOfChannels(); ++i) { | |
89 const float* fifoBusChannel = m_fifoBus->channel(i)->data(); | |
90 float* outputBusChannel = outputBus->channel(i)->mutableData(); | |
91 | |
92 // Fill up the output bus with the available frames first. | |
93 if (remainder >= framesToFill) { | |
94 // The remainder is big enough for the frames to pull. | |
95 memcpy(outputBusChannel, fifoBusChannel + m_indexRead, | |
96 framesToFill * sizeof(*fifoBusChannel)); | |
97 } else { | |
98 // The frames to pull is bigger than the remainder size. | |
99 // Wrap around the index. | |
100 memcpy(outputBusChannel, fifoBusChannel + m_indexRead, | |
101 remainder * sizeof(*fifoBusChannel)); | |
102 memcpy(outputBusChannel + remainder, fifoBusChannel, | |
103 (framesToFill - remainder) * sizeof(*fifoBusChannel)); | |
104 } | |
105 | |
106 // The frames available was not enough to fulfill the requested frames. Fill | |
107 // the rest of the channel with silence. | |
108 if (framesRequested > framesToFill) { | |
109 memset(outputBusChannel + framesToFill, 0, | |
110 (framesRequested - framesToFill) * sizeof(*outputBusChannel)); | |
111 } | |
112 } | |
113 | |
114 // Update the read index; wrap it around if necessary. | |
115 m_indexRead = (m_indexRead + framesToFill) % m_fifoLength; | |
116 | |
117 // In case of underflow, move the |indexWrite| to the updated |indexRead|. | |
118 if (framesRequested > framesToFill) { | |
119 m_indexWrite = m_indexRead; | |
120 if (m_underflowCount++ < kMaxMessagesToLog) { | |
121 DVLOG(1) << "PushPullFIFO: underflow while pulling (" | |
122 << "underflowCount=" << m_underflowCount | |
123 << ", availableFrames=" << m_framesAvailable | |
124 << ", requestedFrames=" << framesRequested | |
125 << ", fifoLength=" << m_fifoLength << ")"; | |
126 } | |
127 } | |
128 | |
129 // Update the number of frames in FIFO. | |
130 m_framesAvailable -= framesToFill; | |
o1ka
2017/02/02 16:30:24
Same here: DCHECK the relations
hongchan
2017/02/02 19:55:23
Ditto.
o1ka
2017/02/03 10:41:17
Ditto :)
hongchan
2017/02/03 17:20:12
Done.
| |
131 } | |
132 | |
133 const PushPullFIFOStateForTest PushPullFIFO::getStateForTest() const { | |
134 return {length(), numberOfChannels(), framesAvailable(), m_indexRead, | |
135 m_indexWrite, m_overflowCount, m_underflowCount}; | |
136 } | |
137 | |
138 } // namespace blink | |
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