2 Copyright (C) 2012-2013 Carl Hetherington <cth@carlh.net>
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #include "audio_buffers.h"
27 using boost::shared_ptr;
29 /** Construct an AudioBuffers. Audio data is undefined after this constructor.
30 * @param channels Number of channels.
31 * @param frames Number of frames to reserve space for.
33 AudioBuffers::AudioBuffers (int channels, int frames)
35 allocate (channels, frames);
39 * @param other Other AudioBuffers; data is copied.
41 AudioBuffers::AudioBuffers (AudioBuffers const & other)
43 allocate (other._channels, other._frames);
44 copy_from (&other, other._frames, 0, 0);
47 AudioBuffers::AudioBuffers (boost::shared_ptr<const AudioBuffers> other)
49 allocate (other->_channels, other->_frames);
50 copy_from (other.get(), other->_frames, 0, 0);
54 AudioBuffers::operator= (AudioBuffers const & other)
61 allocate (other._channels, other._frames);
62 copy_from (&other, other._frames, 0, 0);
67 /** AudioBuffers destructor */
68 AudioBuffers::~AudioBuffers ()
74 AudioBuffers::allocate (int channels, int frames)
78 _allocated_frames = frames;
80 _data = static_cast<float**> (malloc (_channels * sizeof (float *)));
85 for (int i = 0; i < _channels; ++i) {
86 _data[i] = static_cast<float*> (malloc (frames * sizeof (float)));
94 AudioBuffers::deallocate ()
96 for (int i = 0; i < _channels; ++i) {
103 /** @param c Channel index.
104 * @return Buffer for this channel.
107 AudioBuffers::data (int c) const
109 assert (c >= 0 && c < _channels);
113 /** Set the number of frames that these AudioBuffers will report themselves
114 * as having. If we reduce the number of frames, the `lost' frames will
116 * @param f Frames; must be less than or equal to the number of allocated frames.
119 AudioBuffers::set_frames (int f)
121 assert (f <= _allocated_frames);
123 for (int c = 0; c < _channels; ++c) {
124 for (int i = f; i < _frames; ++i) {
132 /** Make all samples on all channels silent */
134 AudioBuffers::make_silent ()
136 for (int i = 0; i < _channels; ++i) {
141 /** Make all samples on a given channel silent.
145 AudioBuffers::make_silent (int c)
147 assert (c >= 0 && c < _channels);
149 for (int i = 0; i < _frames; ++i) {
155 AudioBuffers::make_silent (int from, int frames)
157 assert ((from + frames) <= _allocated_frames);
159 for (int c = 0; c < _channels; ++c) {
160 for (int i = from; i < (from + frames); ++i) {
166 /** Copy data from another AudioBuffers to this one. All channels are copied.
167 * @param from AudioBuffers to copy from; must have the same number of channels as this.
168 * @param frames_to_copy Number of frames to copy.
169 * @param read_offset Offset to read from in `from'.
170 * @param write_offset Offset to write to in `to'.
173 AudioBuffers::copy_from (AudioBuffers const * from, int frames_to_copy, int read_offset, int write_offset)
175 assert (from->channels() == channels());
178 assert (read_offset >= 0 && (read_offset + frames_to_copy) <= from->_allocated_frames);
179 assert (write_offset >= 0 && (write_offset + frames_to_copy) <= _allocated_frames);
181 for (int i = 0; i < _channels; ++i) {
182 memcpy (_data[i] + write_offset, from->_data[i] + read_offset, frames_to_copy * sizeof(float));
186 /** Move audio data around.
187 * @param from Offset to move from.
188 * @param to Offset to move to.
189 * @param frames Number of frames to move.
193 AudioBuffers::move (int from, int to, int frames)
200 assert (from < _frames);
202 assert (to < _frames);
204 assert (frames <= _frames);
205 assert ((from + frames) <= _frames);
206 assert ((to + frames) <= _allocated_frames);
208 for (int i = 0; i < _channels; ++i) {
209 memmove (_data[i] + to, _data[i] + from, frames * sizeof(float));
213 /** Add data from from `from', `from_channel' to our channel `to_channel' */
215 AudioBuffers::accumulate_channel (AudioBuffers const * from, int from_channel, int to_channel)
217 int const N = frames ();
218 assert (from->frames() == N);
219 assert (to_channel <= _channels);
221 float* s = from->data (from_channel);
222 float* d = _data[to_channel];
224 for (int i = 0; i < N; ++i) {
229 /** Ensure we have space for at least a certain number of frames. If we extend
230 * the buffers, fill the new space with silence.
233 AudioBuffers::ensure_size (int frames)
235 if (_allocated_frames >= frames) {
239 for (int i = 0; i < _channels; ++i) {
240 _data[i] = static_cast<float*> (realloc (_data[i], frames * sizeof (float)));
244 for (int j = _allocated_frames; j < frames; ++j) {
249 _allocated_frames = frames;
253 AudioBuffers::accumulate_frames (AudioBuffers const * from, int read_offset, int write_offset, int frames)
255 assert (_channels == from->channels ());
257 for (int i = 0; i < _channels; ++i) {
258 for (int j = 0; j < frames; ++j) {
259 _data[i][j + write_offset] += from->data()[i][j + read_offset];
264 /** @param dB gain in dB */
266 AudioBuffers::apply_gain (float dB)
268 float const linear = pow (10, dB / 20);
270 for (int i = 0; i < _channels; ++i) {
271 for (int j = 0; j < _frames; ++j) {
272 _data[i][j] *= linear;