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
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
|
/*
* Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef COMMON_AUDIO_CHANNEL_BUFFER_H_
#define COMMON_AUDIO_CHANNEL_BUFFER_H_
#include <string.h>
#include <memory>
#include <vector>
#include "api/array_view.h"
#include "common_audio/include/audio_util.h"
#include "rtc_base/checks.h"
#include "rtc_base/gtest_prod_util.h"
namespace webrtc {
// Helper to encapsulate a contiguous data buffer, full or split into frequency
// bands, with access to a pointer arrays of the deinterleaved channels and
// bands. The buffer is zero initialized at creation.
//
// The buffer structure is showed below for a 2 channel and 2 bands case:
//
// |data_|:
// { [ --- b1ch1 --- ] [ --- b2ch1 --- ] [ --- b1ch2 --- ] [ --- b2ch2 --- ] }
//
// The pointer arrays for the same example are as follows:
//
// |channels_|:
// { [ b1ch1* ] [ b1ch2* ] [ b2ch1* ] [ b2ch2* ] }
//
// |bands_|:
// { [ b1ch1* ] [ b2ch1* ] [ b1ch2* ] [ b2ch2* ] }
template <typename T>
class ChannelBuffer {
public:
ChannelBuffer(size_t num_frames, size_t num_channels, size_t num_bands = 1)
: data_(new T[num_frames * num_channels]()),
channels_(new T*[num_channels * num_bands]),
bands_(new T*[num_channels * num_bands]),
num_frames_(num_frames),
num_frames_per_band_(num_frames / num_bands),
num_allocated_channels_(num_channels),
num_channels_(num_channels),
num_bands_(num_bands),
bands_view_(num_allocated_channels_,
std::vector<rtc::ArrayView<T>>(num_bands_)),
channels_view_(
num_bands_,
std::vector<rtc::ArrayView<T>>(num_allocated_channels_)) {
// Temporarily cast away const_ness to allow populating the array views.
auto* bands_view =
const_cast<std::vector<std::vector<rtc::ArrayView<T>>>*>(&bands_view_);
auto* channels_view =
const_cast<std::vector<std::vector<rtc::ArrayView<T>>>*>(
&channels_view_);
for (size_t ch = 0; ch < num_allocated_channels_; ++ch) {
for (size_t band = 0; band < num_bands_; ++band) {
(*channels_view)[band][ch] = rtc::ArrayView<T>(
&data_[ch * num_frames_ + band * num_frames_per_band_],
num_frames_per_band_);
(*bands_view)[ch][band] = channels_view_[band][ch];
channels_[band * num_allocated_channels_ + ch] =
channels_view_[band][ch].data();
bands_[ch * num_bands_ + band] =
channels_[band * num_allocated_channels_ + ch];
}
}
}
// Returns a pointer array to the channels.
// If band is explicitly specificed, the channels for a specific band are
// returned and the usage becomes: channels(band)[channel][sample].
// Where:
// 0 <= band < |num_bands_|
// 0 <= channel < |num_allocated_channels_|
// 0 <= sample < |num_frames_per_band_|
// If band is not explicitly specified, the full-band channels (or lower band
// channels) are returned and the usage becomes: channels()[channel][sample].
// Where:
// 0 <= channel < |num_allocated_channels_|
// 0 <= sample < |num_frames_|
const T* const* channels(size_t band = 0) const {
RTC_DCHECK_LT(band, num_bands_);
return &channels_[band * num_allocated_channels_];
}
T* const* channels(size_t band = 0) {
const ChannelBuffer<T>* t = this;
return const_cast<T* const*>(t->channels(band));
}
rtc::ArrayView<const rtc::ArrayView<T>> channels_view(size_t band = 0) {
return channels_view_[band];
}
rtc::ArrayView<const rtc::ArrayView<T>> channels_view(size_t band = 0) const {
return channels_view_[band];
}
// Returns a pointer array to the bands for a specific channel.
// Usage:
// bands(channel)[band][sample].
// Where:
// 0 <= channel < |num_channels_|
// 0 <= band < |num_bands_|
// 0 <= sample < |num_frames_per_band_|
const T* const* bands(size_t channel) const {
RTC_DCHECK_LT(channel, num_channels_);
RTC_DCHECK_GE(channel, 0);
return &bands_[channel * num_bands_];
}
T* const* bands(size_t channel) {
const ChannelBuffer<T>* t = this;
return const_cast<T* const*>(t->bands(channel));
}
rtc::ArrayView<const rtc::ArrayView<T>> bands_view(size_t channel) {
return bands_view_[channel];
}
rtc::ArrayView<const rtc::ArrayView<T>> bands_view(size_t channel) const {
return bands_view_[channel];
}
// Sets the |slice| pointers to the |start_frame| position for each channel.
// Returns |slice| for convenience.
const T* const* Slice(T** slice, size_t start_frame) const {
RTC_DCHECK_LT(start_frame, num_frames_);
for (size_t i = 0; i < num_channels_; ++i)
slice[i] = &channels_[i][start_frame];
return slice;
}
T** Slice(T** slice, size_t start_frame) {
const ChannelBuffer<T>* t = this;
return const_cast<T**>(t->Slice(slice, start_frame));
}
size_t num_frames() const { return num_frames_; }
size_t num_frames_per_band() const { return num_frames_per_band_; }
size_t num_channels() const { return num_channels_; }
size_t num_bands() const { return num_bands_; }
size_t size() const { return num_frames_ * num_allocated_channels_; }
void set_num_channels(size_t num_channels) {
RTC_DCHECK_LE(num_channels, num_allocated_channels_);
num_channels_ = num_channels;
}
void SetDataForTesting(const T* data, size_t size) {
RTC_CHECK_EQ(size, this->size());
memcpy(data_.get(), data, size * sizeof(*data));
}
private:
std::unique_ptr<T[]> data_;
std::unique_ptr<T*[]> channels_;
std::unique_ptr<T*[]> bands_;
const size_t num_frames_;
const size_t num_frames_per_band_;
// Number of channels the internal buffer holds.
const size_t num_allocated_channels_;
// Number of channels the user sees.
size_t num_channels_;
const size_t num_bands_;
const std::vector<std::vector<rtc::ArrayView<T>>> bands_view_;
const std::vector<std::vector<rtc::ArrayView<T>>> channels_view_;
};
// One int16_t and one float ChannelBuffer that are kept in sync. The sync is
// broken when someone requests write access to either ChannelBuffer, and
// reestablished when someone requests the outdated ChannelBuffer. It is
// therefore safe to use the return value of ibuf_const() and fbuf_const()
// until the next call to ibuf() or fbuf(), and the return value of ibuf() and
// fbuf() until the next call to any of the other functions.
class IFChannelBuffer {
public:
IFChannelBuffer(size_t num_frames, size_t num_channels, size_t num_bands = 1);
~IFChannelBuffer();
ChannelBuffer<int16_t>* ibuf();
ChannelBuffer<float>* fbuf();
const ChannelBuffer<int16_t>* ibuf_const() const;
const ChannelBuffer<float>* fbuf_const() const;
size_t num_frames() const { return ibuf_.num_frames(); }
size_t num_frames_per_band() const { return ibuf_.num_frames_per_band(); }
size_t num_channels() const {
return ivalid_ ? ibuf_.num_channels() : fbuf_.num_channels();
}
void set_num_channels(size_t num_channels) {
ibuf_.set_num_channels(num_channels);
fbuf_.set_num_channels(num_channels);
}
size_t num_bands() const { return ibuf_.num_bands(); }
private:
void RefreshF() const;
void RefreshI() const;
mutable bool ivalid_;
mutable ChannelBuffer<int16_t> ibuf_;
mutable bool fvalid_;
mutable ChannelBuffer<float> fbuf_;
};
} // namespace webrtc
#endif // COMMON_AUDIO_CHANNEL_BUFFER_H_
|
