annotate data/fileio/CodedAudioFileReader.cpp @ 1229:e699bdeef63c piper

Add files that I forgot to track on Friday (sigh)
author Chris Cannam
date Tue, 25 Oct 2016 10:53:12 +0100
parents 6877f4200912
children 0a9193dc136b
rev   line source
Chris@148 1 /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */
Chris@148 2
Chris@148 3 /*
Chris@148 4 Sonic Visualiser
Chris@148 5 An audio file viewer and annotation editor.
Chris@148 6 Centre for Digital Music, Queen Mary, University of London.
Chris@297 7 This file copyright 2006-2007 Chris Cannam and QMUL.
Chris@148 8
Chris@148 9 This program is free software; you can redistribute it and/or
Chris@148 10 modify it under the terms of the GNU General Public License as
Chris@148 11 published by the Free Software Foundation; either version 2 of the
Chris@148 12 License, or (at your option) any later version. See the file
Chris@148 13 COPYING included with this distribution for more information.
Chris@148 14 */
Chris@148 15
Chris@148 16 #include "CodedAudioFileReader.h"
Chris@148 17
Chris@148 18 #include "WavFileReader.h"
Chris@148 19 #include "base/TempDirectory.h"
Chris@148 20 #include "base/Exceptions.h"
Chris@192 21 #include "base/Profiler.h"
Chris@297 22 #include "base/Serialiser.h"
Chris@297 23 #include "base/Resampler.h"
Chris@1098 24 #include "base/StorageAdviser.h"
Chris@148 25
Chris@723 26 #include <stdint.h>
Chris@148 27 #include <iostream>
Chris@148 28 #include <QDir>
Chris@263 29 #include <QMutexLocker>
Chris@148 30
Chris@1096 31 using namespace std;
Chris@1096 32
Chris@297 33 CodedAudioFileReader::CodedAudioFileReader(CacheMode cacheMode,
Chris@1040 34 sv_samplerate_t targetRate,
Chris@920 35 bool normalised) :
Chris@148 36 m_cacheMode(cacheMode),
Chris@148 37 m_initialised(false),
Chris@297 38 m_serialiser(0),
Chris@297 39 m_fileRate(0),
Chris@148 40 m_cacheFileWritePtr(0),
Chris@148 41 m_cacheFileReader(0),
Chris@148 42 m_cacheWriteBuffer(0),
Chris@148 43 m_cacheWriteBufferIndex(0),
Chris@297 44 m_cacheWriteBufferSize(16384),
Chris@297 45 m_resampler(0),
Chris@757 46 m_resampleBuffer(0),
Chris@920 47 m_fileFrameCount(0),
Chris@920 48 m_normalised(normalised),
Chris@920 49 m_max(0.f),
Chris@920 50 m_gain(1.f)
Chris@148 51 {
Chris@922 52 SVDEBUG << "CodedAudioFileReader::CodedAudioFileReader: rate " << targetRate << ", normalised = " << normalised << endl;
Chris@297 53
Chris@297 54 m_frameCount = 0;
Chris@297 55 m_sampleRate = targetRate;
Chris@148 56 }
Chris@148 57
Chris@148 58 CodedAudioFileReader::~CodedAudioFileReader()
Chris@148 59 {
Chris@263 60 QMutexLocker locker(&m_cacheMutex);
Chris@263 61
Chris@297 62 endSerialised();
Chris@1098 63
Chris@148 64 if (m_cacheFileWritePtr) sf_close(m_cacheFileWritePtr);
Chris@297 65
Chris@742 66 SVDEBUG << "CodedAudioFileReader::~CodedAudioFileReader: deleting cache file reader" << endl;
Chris@532 67
Chris@297 68 delete m_cacheFileReader;
Chris@297 69 delete[] m_cacheWriteBuffer;
Chris@148 70
Chris@148 71 if (m_cacheFileName != "") {
Chris@290 72 if (!QFile(m_cacheFileName).remove()) {
Chris@843 73 cerr << "WARNING: CodedAudioFileReader::~CodedAudioFileReader: Failed to delete cache file \"" << m_cacheFileName << "\"" << endl;
Chris@148 74 }
Chris@148 75 }
Chris@297 76
Chris@297 77 delete m_resampler;
Chris@297 78 delete[] m_resampleBuffer;
Chris@1098 79
Chris@1098 80 if (!m_data.empty()) {
Chris@1098 81 StorageAdviser::notifyDoneAllocation
Chris@1098 82 (StorageAdviser::MemoryAllocation,
Chris@1098 83 (m_data.size() * sizeof(float)) / 1024);
Chris@1098 84 }
Chris@297 85 }
Chris@297 86
Chris@297 87 void
Chris@297 88 CodedAudioFileReader::startSerialised(QString id)
Chris@297 89 {
Chris@742 90 SVDEBUG << "CodedAudioFileReader::startSerialised(" << id << ")" << endl;
Chris@297 91
Chris@297 92 delete m_serialiser;
Chris@297 93 m_serialiser = new Serialiser(id);
Chris@297 94 }
Chris@297 95
Chris@297 96 void
Chris@297 97 CodedAudioFileReader::endSerialised()
Chris@297 98 {
Chris@844 99 SVDEBUG << "CodedAudioFileReader(" << this << ")::endSerialised: id = " << (m_serialiser ? m_serialiser->getId() : "(none)") << endl;
Chris@297 100
Chris@297 101 delete m_serialiser;
Chris@297 102 m_serialiser = 0;
Chris@148 103 }
Chris@148 104
Chris@148 105 void
Chris@148 106 CodedAudioFileReader::initialiseDecodeCache()
Chris@148 107 {
Chris@263 108 QMutexLocker locker(&m_cacheMutex);
Chris@263 109
Chris@742 110 SVDEBUG << "CodedAudioFileReader::initialiseDecodeCache: file rate = " << m_fileRate << endl;
Chris@297 111
Chris@297 112 if (m_fileRate == 0) {
Chris@843 113 cerr << "CodedAudioFileReader::initialiseDecodeCache: ERROR: File sample rate unknown (bug in subclass implementation?)" << endl;
Chris@754 114 throw FileOperationFailed("(coded file)", "File sample rate unknown (bug in subclass implementation?)");
Chris@297 115 }
Chris@297 116 if (m_sampleRate == 0) {
Chris@297 117 m_sampleRate = m_fileRate;
Chris@690 118 SVDEBUG << "CodedAudioFileReader::initialiseDecodeCache: rate (from file) = " << m_fileRate << endl;
Chris@297 119 }
Chris@297 120 if (m_fileRate != m_sampleRate) {
Chris@757 121 SVDEBUG << "CodedAudioFileReader: resampling " << m_fileRate << " -> " << m_sampleRate << endl;
Chris@297 122 m_resampler = new Resampler(Resampler::FastestTolerable,
Chris@297 123 m_channelCount,
Chris@297 124 m_cacheWriteBufferSize);
Chris@1040 125 double ratio = m_sampleRate / m_fileRate;
Chris@297 126 m_resampleBuffer = new float
Chris@1038 127 [lrint(ceil(double(m_cacheWriteBufferSize) * m_channelCount * ratio + 1))];
Chris@297 128 }
Chris@297 129
Chris@297 130 m_cacheWriteBuffer = new float[m_cacheWriteBufferSize * m_channelCount];
Chris@297 131 m_cacheWriteBufferIndex = 0;
Chris@297 132
Chris@148 133 if (m_cacheMode == CacheInTemporaryFile) {
Chris@148 134
Chris@148 135 try {
Chris@148 136 QDir dir(TempDirectory::getInstance()->getPath());
Chris@148 137 m_cacheFileName = dir.filePath(QString("decoded_%1.wav")
Chris@290 138 .arg((intptr_t)this));
Chris@148 139
Chris@148 140 SF_INFO fileInfo;
Chris@1040 141 int fileRate = int(round(m_sampleRate));
Chris@1040 142 if (m_sampleRate != sv_samplerate_t(fileRate)) {
Chris@1040 143 cerr << "CodedAudioFileReader: WARNING: Non-integer sample rate "
Chris@1040 144 << m_sampleRate << " presented for writing, rounding to " << fileRate
Chris@1040 145 << endl;
Chris@1040 146 }
Chris@1040 147 fileInfo.samplerate = fileRate;
Chris@148 148 fileInfo.channels = m_channelCount;
Chris@1161 149
Chris@1161 150 // Previously we were writing SF_FORMAT_PCM_16 and in a
Chris@1161 151 // comment I wrote: "No point in writing 24-bit or float;
Chris@1161 152 // generally this class is used for decoding files that
Chris@1161 153 // have come from a 16 bit source or that decode to only
Chris@1161 154 // 16 bits anyway." That was naive -- we want to preserve
Chris@1161 155 // the original values to the same float precision that we
Chris@1161 156 // use internally. Saving PCM_16 obviously doesn't
Chris@1161 157 // preserve values for sources at bit depths greater than
Chris@1161 158 // 16, but it also doesn't always do so for sources at bit
Chris@1161 159 // depths less than 16.
Chris@1161 160 //
Chris@1161 161 // (This came to light with a bug in libsndfile 1.0.26,
Chris@1161 162 // which always reports every file as non-seekable, so
Chris@1161 163 // that coded readers were being used even for WAV
Chris@1161 164 // files. This changed the values that came from PCM_8 WAV
Chris@1161 165 // sources, breaking Sonic Annotator's output comparison
Chris@1161 166 // tests.)
Chris@1161 167 //
Chris@1161 168 // So: now we write floats.
Chris@1161 169 fileInfo.format = SF_FORMAT_WAV | SF_FORMAT_FLOAT;
Chris@148 170
Chris@290 171 m_cacheFileWritePtr = sf_open(m_cacheFileName.toLocal8Bit(),
Chris@148 172 SFM_WRITE, &fileInfo);
Chris@148 173
Chris@265 174 if (m_cacheFileWritePtr) {
Chris@265 175
Chris@297 176 // Ideally we would do this now only if we were in a
Chris@297 177 // threaded mode -- creating the reader later if we're
Chris@297 178 // not threaded -- but we don't have access to that
Chris@297 179 // information here
Chris@265 180
Chris@265 181 m_cacheFileReader = new WavFileReader(m_cacheFileName);
Chris@265 182
Chris@265 183 if (!m_cacheFileReader->isOK()) {
Chris@843 184 cerr << "ERROR: CodedAudioFileReader::initialiseDecodeCache: Failed to construct WAV file reader for temporary file: " << m_cacheFileReader->getError() << endl;
Chris@265 185 delete m_cacheFileReader;
Chris@265 186 m_cacheFileReader = 0;
Chris@265 187 m_cacheMode = CacheInMemory;
Chris@265 188 sf_close(m_cacheFileWritePtr);
Chris@265 189 }
Chris@297 190
Chris@265 191 } else {
Chris@843 192 cerr << "CodedAudioFileReader::initialiseDecodeCache: failed to open cache file \"" << m_cacheFileName << "\" (" << m_channelCount << " channels, sample rate " << m_sampleRate << " for writing, falling back to in-memory cache" << endl;
Chris@148 193 m_cacheMode = CacheInMemory;
Chris@148 194 }
Chris@265 195
Chris@148 196 } catch (DirectoryCreationFailed f) {
Chris@843 197 cerr << "CodedAudioFileReader::initialiseDecodeCache: failed to create temporary directory! Falling back to in-memory cache" << endl;
Chris@148 198 m_cacheMode = CacheInMemory;
Chris@148 199 }
Chris@148 200 }
Chris@148 201
Chris@148 202 if (m_cacheMode == CacheInMemory) {
Chris@148 203 m_data.clear();
Chris@148 204 }
Chris@148 205
Chris@148 206 m_initialised = true;
Chris@148 207 }
Chris@148 208
Chris@148 209 void
Chris@1038 210 CodedAudioFileReader::addSamplesToDecodeCache(float **samples, sv_frame_t nframes)
Chris@148 211 {
Chris@263 212 QMutexLocker locker(&m_cacheMutex);
Chris@263 213
Chris@148 214 if (!m_initialised) return;
Chris@148 215
Chris@1038 216 for (sv_frame_t i = 0; i < nframes; ++i) {
Chris@297 217
Chris@929 218 for (int c = 0; c < m_channelCount; ++c) {
Chris@148 219
Chris@297 220 float sample = samples[c][i];
Chris@297 221
Chris@297 222 m_cacheWriteBuffer[m_cacheWriteBufferIndex++] = sample;
Chris@148 223
Chris@297 224 if (m_cacheWriteBufferIndex ==
Chris@297 225 m_cacheWriteBufferSize * m_channelCount) {
Chris@297 226
Chris@297 227 pushBuffer(m_cacheWriteBuffer, m_cacheWriteBufferSize, false);
Chris@297 228 m_cacheWriteBufferIndex = 0;
Chris@297 229 }
Chris@297 230
Chris@297 231 if (m_cacheWriteBufferIndex % 10240 == 0 &&
Chris@297 232 m_cacheFileReader) {
Chris@297 233 m_cacheFileReader->updateFrameCount();
Chris@297 234 }
Chris@297 235 }
Chris@297 236 }
Chris@297 237 }
Chris@297 238
Chris@297 239 void
Chris@1038 240 CodedAudioFileReader::addSamplesToDecodeCache(float *samples, sv_frame_t nframes)
Chris@297 241 {
Chris@297 242 QMutexLocker locker(&m_cacheMutex);
Chris@297 243
Chris@297 244 if (!m_initialised) return;
Chris@297 245
Chris@1038 246 for (sv_frame_t i = 0; i < nframes; ++i) {
Chris@297 247
Chris@929 248 for (int c = 0; c < m_channelCount; ++c) {
Chris@297 249
Chris@297 250 float sample = samples[i * m_channelCount + c];
Chris@297 251
Chris@297 252 m_cacheWriteBuffer[m_cacheWriteBufferIndex++] = sample;
Chris@297 253
Chris@297 254 if (m_cacheWriteBufferIndex ==
Chris@297 255 m_cacheWriteBufferSize * m_channelCount) {
Chris@297 256
Chris@297 257 pushBuffer(m_cacheWriteBuffer, m_cacheWriteBufferSize, false);
Chris@297 258 m_cacheWriteBufferIndex = 0;
Chris@297 259 }
Chris@297 260
Chris@297 261 if (m_cacheWriteBufferIndex % 10240 == 0 &&
Chris@297 262 m_cacheFileReader) {
Chris@297 263 m_cacheFileReader->updateFrameCount();
Chris@297 264 }
Chris@297 265 }
Chris@297 266 }
Chris@297 267 }
Chris@297 268
Chris@297 269 void
Chris@1096 270 CodedAudioFileReader::addSamplesToDecodeCache(const vector<float> &samples)
Chris@297 271 {
Chris@297 272 QMutexLocker locker(&m_cacheMutex);
Chris@297 273
Chris@297 274 if (!m_initialised) return;
Chris@297 275
Chris@1038 276 for (float sample: samples) {
Chris@297 277
Chris@148 278 m_cacheWriteBuffer[m_cacheWriteBufferIndex++] = sample;
Chris@148 279
Chris@148 280 if (m_cacheWriteBufferIndex ==
Chris@148 281 m_cacheWriteBufferSize * m_channelCount) {
Chris@148 282
Chris@297 283 pushBuffer(m_cacheWriteBuffer, m_cacheWriteBufferSize, false);
Chris@148 284 m_cacheWriteBufferIndex = 0;
Chris@266 285 }
Chris@265 286
Chris@266 287 if (m_cacheWriteBufferIndex % 10240 == 0 &&
Chris@266 288 m_cacheFileReader) {
Chris@266 289 m_cacheFileReader->updateFrameCount();
Chris@148 290 }
Chris@148 291 }
Chris@148 292 }
Chris@148 293
Chris@148 294 void
Chris@148 295 CodedAudioFileReader::finishDecodeCache()
Chris@148 296 {
Chris@263 297 QMutexLocker locker(&m_cacheMutex);
Chris@263 298
Chris@192 299 Profiler profiler("CodedAudioFileReader::finishDecodeCache", true);
Chris@192 300
Chris@148 301 if (!m_initialised) {
Chris@843 302 cerr << "WARNING: CodedAudioFileReader::finishDecodeCache: Cache was never initialised!" << endl;
Chris@148 303 return;
Chris@148 304 }
Chris@148 305
Chris@920 306 pushBuffer(m_cacheWriteBuffer,
Chris@920 307 m_cacheWriteBufferIndex / m_channelCount,
Chris@920 308 true);
Chris@297 309
Chris@297 310 delete[] m_cacheWriteBuffer;
Chris@297 311 m_cacheWriteBuffer = 0;
Chris@297 312
Chris@297 313 delete[] m_resampleBuffer;
Chris@297 314 m_resampleBuffer = 0;
Chris@297 315
Chris@297 316 delete m_resampler;
Chris@297 317 m_resampler = 0;
Chris@297 318
Chris@297 319 if (m_cacheMode == CacheInTemporaryFile) {
Chris@1098 320
Chris@297 321 sf_close(m_cacheFileWritePtr);
Chris@297 322 m_cacheFileWritePtr = 0;
Chris@297 323 if (m_cacheFileReader) m_cacheFileReader->updateFrameCount();
Chris@1098 324
Chris@1098 325 } else {
Chris@1098 326 // I know, I know, we already allocated it...
Chris@1098 327 StorageAdviser::notifyPlannedAllocation
Chris@1098 328 (StorageAdviser::MemoryAllocation,
Chris@1098 329 (m_data.size() * sizeof(float)) / 1024);
Chris@297 330 }
Chris@297 331 }
Chris@297 332
Chris@297 333 void
Chris@1038 334 CodedAudioFileReader::pushBuffer(float *buffer, sv_frame_t sz, bool final)
Chris@297 335 {
Chris@757 336 m_fileFrameCount += sz;
Chris@757 337
Chris@1040 338 double ratio = 1.0;
Chris@758 339 if (m_resampler && m_fileRate != 0) {
Chris@1040 340 ratio = m_sampleRate / m_fileRate;
Chris@758 341 }
Chris@758 342
Chris@1040 343 if (ratio != 1.0) {
Chris@758 344 pushBufferResampling(buffer, sz, ratio, final);
Chris@758 345 } else {
Chris@758 346 pushBufferNonResampling(buffer, sz);
Chris@758 347 }
Chris@758 348 }
Chris@757 349
Chris@758 350 void
Chris@1038 351 CodedAudioFileReader::pushBufferNonResampling(float *buffer, sv_frame_t sz)
Chris@758 352 {
Chris@920 353 float clip = 1.0;
Chris@1038 354 sv_frame_t count = sz * m_channelCount;
Chris@318 355
Chris@920 356 if (m_normalised) {
Chris@1038 357 for (sv_frame_t i = 0; i < count; ++i) {
Chris@920 358 float v = fabsf(buffer[i]);
Chris@920 359 if (v > m_max) {
Chris@920 360 m_max = v;
Chris@920 361 m_gain = 1.f / m_max;
Chris@920 362 }
Chris@920 363 }
Chris@920 364 } else {
Chris@1038 365 for (sv_frame_t i = 0; i < count; ++i) {
Chris@920 366 if (buffer[i] > clip) buffer[i] = clip;
Chris@920 367 }
Chris@1038 368 for (sv_frame_t i = 0; i < count; ++i) {
Chris@920 369 if (buffer[i] < -clip) buffer[i] = -clip;
Chris@920 370 }
Chris@297 371 }
Chris@297 372
Chris@297 373 m_frameCount += sz;
Chris@297 374
Chris@148 375 switch (m_cacheMode) {
Chris@148 376
Chris@148 377 case CacheInTemporaryFile:
Chris@1038 378 if (sf_writef_float(m_cacheFileWritePtr, buffer, sz) < sz) {
Chris@544 379 sf_close(m_cacheFileWritePtr);
Chris@544 380 m_cacheFileWritePtr = 0;
Chris@544 381 throw InsufficientDiscSpace(TempDirectory::getInstance()->getPath());
Chris@544 382 }
Chris@148 383 break;
Chris@148 384
Chris@148 385 case CacheInMemory:
Chris@1100 386 m_dataLock.lock();
Chris@1096 387 m_data.insert(m_data.end(), buffer, buffer + count);
Chris@543 388 m_dataLock.unlock();
Chris@148 389 break;
Chris@148 390 }
Chris@758 391 }
Chris@757 392
Chris@758 393 void
Chris@1038 394 CodedAudioFileReader::pushBufferResampling(float *buffer, sv_frame_t sz,
Chris@1038 395 double ratio, bool final)
Chris@758 396 {
Chris@759 397 SVDEBUG << "pushBufferResampling: ratio = " << ratio << ", sz = " << sz << ", final = " << final << endl;
Chris@757 398
Chris@759 399 if (sz > 0) {
Chris@759 400
Chris@1038 401 sv_frame_t out = m_resampler->resampleInterleaved
Chris@759 402 (buffer,
Chris@759 403 m_resampleBuffer,
Chris@759 404 sz,
Chris@759 405 ratio,
Chris@759 406 false);
Chris@759 407
Chris@759 408 pushBufferNonResampling(m_resampleBuffer, out);
Chris@759 409 }
Chris@757 410
Chris@758 411 if (final) {
Chris@758 412
Chris@1038 413 sv_frame_t padFrames = 1;
Chris@1038 414 if (double(m_frameCount) / ratio < double(m_fileFrameCount)) {
Chris@1038 415 padFrames = m_fileFrameCount - sv_frame_t(double(m_frameCount) / ratio) + 1;
Chris@757 416 }
Chris@758 417
Chris@1038 418 sv_frame_t padSamples = padFrames * m_channelCount;
Chris@758 419
Chris@1038 420 SVDEBUG << "frameCount = " << m_frameCount << ", equivFileFrames = " << double(m_frameCount) / ratio << ", m_fileFrameCount = " << m_fileFrameCount << ", padFrames= " << padFrames << ", padSamples = " << padSamples << endl;
Chris@758 421
Chris@758 422 float *padding = new float[padSamples];
Chris@1038 423 for (sv_frame_t i = 0; i < padSamples; ++i) padding[i] = 0.f;
Chris@758 424
Chris@1038 425 sv_frame_t out = m_resampler->resampleInterleaved
Chris@758 426 (padding,
Chris@758 427 m_resampleBuffer,
Chris@758 428 padFrames,
Chris@758 429 ratio,
Chris@758 430 true);
Chris@758 431
Chris@1038 432 if (m_frameCount + out > sv_frame_t(double(m_fileFrameCount) * ratio)) {
Chris@1038 433 out = sv_frame_t(double(m_fileFrameCount) * ratio) - m_frameCount;
Chris@759 434 }
Chris@759 435
Chris@758 436 pushBufferNonResampling(m_resampleBuffer, out);
Chris@758 437 delete[] padding;
Chris@757 438 }
Chris@148 439 }
Chris@148 440
Chris@1096 441 vector<float>
Chris@1041 442 CodedAudioFileReader::getInterleavedFrames(sv_frame_t start, sv_frame_t count) const
Chris@148 443 {
Chris@543 444 // Lock is only required in CacheInMemory mode (the cache file
Chris@543 445 // reader is expected to be thread safe and manage its own
Chris@543 446 // locking)
Chris@263 447
Chris@265 448 if (!m_initialised) {
Chris@690 449 SVDEBUG << "CodedAudioFileReader::getInterleavedFrames: not initialised" << endl;
Chris@1096 450 return {};
Chris@265 451 }
Chris@148 452
Chris@1096 453 vector<float> frames;
Chris@1041 454
Chris@148 455 switch (m_cacheMode) {
Chris@148 456
Chris@148 457 case CacheInTemporaryFile:
Chris@148 458 if (m_cacheFileReader) {
Chris@1041 459 frames = m_cacheFileReader->getInterleavedFrames(start, count);
Chris@148 460 }
Chris@148 461 break;
Chris@148 462
Chris@148 463 case CacheInMemory:
Chris@148 464 {
Chris@1096 465 if (!isOK()) return {};
Chris@1096 466 if (count == 0) return {};
Chris@148 467
Chris@1100 468 sv_frame_t ix0 = start * m_channelCount;
Chris@1100 469 sv_frame_t ix1 = ix0 + (count * m_channelCount);
Chris@148 470
Chris@1052 471
Chris@1100 472 // This lock used to be a QReadWriteLock, but it appears that
Chris@1100 473 // its lock mechanism is significantly slower than QMutex so
Chris@1100 474 // it's not a good idea in cases like this where we don't
Chris@1100 475 // really have threads taking a long time to read concurrently
Chris@1100 476 m_dataLock.lock();
Chris@1100 477 sv_frame_t n = sv_frame_t(m_data.size());
Chris@1100 478 if (ix1 > n) ix1 = n;
Chris@1100 479 frames = vector<float>(m_data.begin() + ix0, m_data.begin() + ix1);
Chris@543 480 m_dataLock.unlock();
Chris@148 481 }
Chris@148 482 }
Chris@920 483
Chris@920 484 if (m_normalised) {
Chris@1052 485 for (auto &f: frames) f *= m_gain;
Chris@920 486 }
Chris@1041 487
Chris@1041 488 return frames;
Chris@148 489 }
Chris@148 490