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
|
/*
Copyright (C) 2012-2021 Carl Hetherington <cth@carlh.net>
This file is part of libdcp.
libdcp is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
libdcp is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with libdcp. If not, see <http://www.gnu.org/licenses/>.
In addition, as a special exception, the copyright holders give
permission to link the code of portions of this program with the
OpenSSL library under certain conditions as described in each
individual source file, and distribute linked combinations
including the two.
You must obey the GNU General Public License in all respects
for all of the code used other than OpenSSL. If you modify
file(s) with this exception, you may extend this exception to your
version of the file(s), but you are not obligated to do so. If you
do not wish to do so, delete this exception statement from your
version. If you delete this exception statement from all source
files in the program, then also delete it here.
*/
/** @file src/sound_asset_writer.h
* @brief SoundAssetWriter class
*/
#include "asset_writer.h"
#include "dcp_assert.h"
#include "fsk.h"
#include "sound_asset.h"
#include "sound_frame.h"
#include <memory>
#include <boost/filesystem.hpp>
#include <boost/shared_array.hpp>
struct sync_test1;
namespace dcp {
namespace sound_asset_writer {
template <typename T>
int32_t convert(T) { return {}; }
template <>
inline int32_t convert(int32_t x)
{
int constexpr clip = (1 << 23);
return std::max(-clip, std::min(clip, x));
}
template<>
inline int32_t convert(float x)
{
float constexpr clip = 1.0f - (1.0f / (1 << 23));
float constexpr scale = (1 << 23);
auto const clipped = std::max(-clip, std::min(clip, x));
return std::lround(clipped * scale);
}
}
class SoundAsset;
/** @class SoundAssetWriter
* @brief A helper class for writing to SoundAssets.
*
* Objects of this class can only be created with SoundAsset::start_write().
*
* Sound samples can be written to the SoundAsset by calling write() with
* a buffer of float values. finalize() must be called after the last samples
* have been written.
*/
class SoundAssetWriter : public AssetWriter
{
public:
~SoundAssetWriter();
/** @param data Pointer an array of float pointers, one for each channel.
* @param channels Number of channels in data; if this is less than the channels in the asset
* the remaining asset channels will be padded with silence.
* @param frames Number of frames i.e. number of floats that are given for each channel.
*/
void write(float const * const * data, int channels, int frames);
/** @param data Pointer an array of int32_t pointers, one for each channel.
* The 24-bit audio sample should be in the lower 24 bits of the int32_t.
* @param channels Number of channels in data; if this is less than the channels in the asset
* the remaining asset channels will be padded with silence.
* @param frames Number of frames i.e. number of floats that are given for each channel.
*/
void write(int32_t const * const * data, int channels, int frames);
bool finalize () override;
private:
friend class SoundAsset;
friend struct ::sync_test1;
byte_t* frame_buffer_data() const;
int frame_buffer_capacity() const;
template <class T>
void
do_write(T const * const * data, int data_channels, int frames)
{
DCP_ASSERT(!_finalized);
DCP_ASSERT(frames > 0);
auto const asset_channels = _asset->channels();
DCP_ASSERT(data_channels <= asset_channels);
if (!_started) {
start();
}
for (int i = 0; i < frames; ++i) {
auto out = frame_buffer_data() + _frame_buffer_offset;
/* Write one sample per asset channel */
for (int j = 0; j < asset_channels; ++j) {
int32_t s = 0;
if (j == 13 && _sync) {
s = _fsk.get();
} else if (j < data_channels) {
s = sound_asset_writer::convert(data[j][i]);
}
*out++ = (s & 0xff);
*out++ = (s & 0xff00) >> 8;
*out++ = (s & 0xff0000) >> 16;
}
_frame_buffer_offset += 3 * asset_channels;
DCP_ASSERT(_frame_buffer_offset <= frame_buffer_capacity());
/* Finish the MXF frame if required */
if (_frame_buffer_offset == frame_buffer_capacity()) {
write_current_frame();
_frame_buffer_offset = 0;
memset(frame_buffer_data(), 0, frame_buffer_capacity());
}
}
}
SoundAssetWriter(SoundAsset *, boost::filesystem::path, std::vector<dcp::Channel> extra_active_channels, bool sync, bool include_mca_subdescriptors);
void start ();
void write_current_frame ();
std::vector<bool> create_sync_packets ();
/* do this with an opaque pointer so we don't have to include
ASDCP headers
*/
struct ASDCPState;
std::shared_ptr<ASDCPState> _state;
SoundAsset* _asset = nullptr;
int _frame_buffer_offset = 0;
std::vector<dcp::Channel> _extra_active_channels;
/** true to ignore any signal passed to write() on channel 14 and instead write a sync track */
bool _sync = false;
/** index of the sync packet (0-3) which starts the next edit unit */
int _sync_packet = 0;
FSK _fsk;
bool _include_mca_subdescriptors = true;
};
}
|
