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#include "engine/enginebufferscalest.h"
// Fixes redefinition warnings from SoundTouch.
#undef TRUE
#undef FALSE
#include <SoundTouch.h>
#include "control/controlobject.h"
#include "engine/engineobject.h"
#include "engine/readaheadmanager.h"
#include "track/keyutils.h"
#include "util/math.h"
#include "util/sample.h"
using namespace soundtouch;
namespace {
// Due to filtering and oversampling, SoundTouch is some samples behind.
// The value below was experimental identified using a saw signal and SoundTouch 1.8
// at a speed of 1.0
// 0.918 (upscaling 44.1 kHz to 48 kHz) will produce an additional offset of 3 Frames
// 0.459 (upscaling 44.1 kHz to 96 kHz) will produce an additional offset of 18 Frames
// (Rubberband does not suffer this issue)
const SINT kSeekOffsetFrames = 519;
} // namespace
EngineBufferScaleST::EngineBufferScaleST(ReadAheadManager *pReadAheadManager)
: m_pReadAheadManager(pReadAheadManager),
m_pSoundTouch(std::make_unique<soundtouch::SoundTouch>()),
buffer_back_size(getAudioSignal().frames2samples(kSeekOffsetFrames)),
buffer_back(SampleUtil::alloc(buffer_back_size)),
m_bBackwards(false) {
DEBUG_ASSERT(getAudioSignal().verifyReadable());
m_pSoundTouch->setChannels(getAudioSignal().channelCount());
m_pSoundTouch->setSampleRate(getAudioSignal().sampleRate());
m_pSoundTouch->setRate(m_dBaseRate);
m_pSoundTouch->setPitch(1.0);
m_pSoundTouch->setSetting(SETTING_USE_QUICKSEEK, 1);
// Setting the tempo to a very low value will force SoundTouch
// to preallocate buffers large enough to (almost certainly)
// avoid memory reallocations during playback.
m_pSoundTouch->setTempo(0.1);
m_pSoundTouch->putSamples(buffer_back, kSeekOffsetFrames);
m_pSoundTouch->clear();
m_pSoundTouch->setTempo(m_dTempoRatio);
}
EngineBufferScaleST::~EngineBufferScaleST() {
SampleUtil::free(buffer_back);
}
void EngineBufferScaleST::setScaleParameters(double base_rate,
double* pTempoRatio,
double* pPitchRatio) {
// Negative speed means we are going backwards. pitch does not affect
// the playback direction.
m_bBackwards = *pTempoRatio < 0;
// It's an error to pass a rate or tempo smaller than MIN_SEEK_SPEED to
// SoundTouch (see definition of MIN_SEEK_SPEED for more details).
double speed_abs = fabs(*pTempoRatio);
if (speed_abs > MAX_SEEK_SPEED) {
speed_abs = MAX_SEEK_SPEED;
} else if (speed_abs < MIN_SEEK_SPEED) {
speed_abs = 0;
}
// Let the caller know if we clamped their value.
*pTempoRatio = m_bBackwards ? -speed_abs : speed_abs;
// Include baserate in rate_abs so that we do samplerate conversion as part
// of rate adjustment.
if (speed_abs != m_dTempoRatio) {
// Note: A rate of zero would make Soundtouch crash,
// this is caught in scaleBuffer()
m_pSoundTouch->setTempo(speed_abs);
m_dTempoRatio = speed_abs;
}
if (base_rate != m_dBaseRate) {
m_pSoundTouch->setRate(base_rate);
m_dBaseRate = base_rate;
}
if (*pPitchRatio != m_dPitchRatio) {
// Note: pitch ratio must be positive
double pitch = fabs(*pPitchRatio);
if (pitch > 0.0) {
m_pSoundTouch->setPitch(pitch);
}
m_dPitchRatio = *pPitchRatio;
}
// NOTE(rryan) : There used to be logic here that clear()'d when the player
// changed direction. I removed it because this is handled by EngineBuffer.
}
void EngineBufferScaleST::setSampleRate(SINT iSampleRate) {
EngineBufferScale::setSampleRate(iSampleRate);
m_pSoundTouch->setSampleRate(iSampleRate);
}
void EngineBufferScaleST::clear() {
m_pSoundTouch->clear();
// compensate seek offset for a rate of 1.0
SampleUtil::clear(buffer_back, getAudioSignal().frames2samples(kSeekOffsetFrames));
m_pSoundTouch->putSamples(buffer_back, kSeekOffsetFrames);
}
double EngineBufferScaleST::scaleBuffer(
CSAMPLE* pOutputBuffer,
SINT iOutputBufferSize) {
if (m_dBaseRate == 0.0 || m_dTempoRatio == 0.0 || m_dPitchRatio == 0.0) {
SampleUtil::clear(pOutputBuffer, iOutputBufferSize);
// No actual samples/frames have been read from the
// unscaled input buffer!
return 0.0;
}
SINT total_received_frames = 0;
SINT total_read_frames = 0;
SINT remaining_frames = getAudioSignal().samples2frames(iOutputBufferSize);
CSAMPLE* read = pOutputBuffer;
bool last_read_failed = false;
while (remaining_frames > 0) {
SINT received_frames = m_pSoundTouch->receiveSamples(
read, remaining_frames);
DEBUG_ASSERT(remaining_frames >= received_frames);
remaining_frames -= received_frames;
total_received_frames += received_frames;
read += getAudioSignal().frames2samples(received_frames);
if (remaining_frames > 0) {
SINT iAvailSamples = m_pReadAheadManager->getNextSamples(
// The value doesn't matter here. All that matters is we
// are going forward or backward.
(m_bBackwards ? -1.0 : 1.0) * m_dBaseRate * m_dTempoRatio,
buffer_back,
buffer_back_size);
SINT iAvailFrames = getAudioSignal().samples2frames(iAvailSamples);
if (iAvailFrames > 0) {
last_read_failed = false;
total_read_frames += iAvailFrames;
m_pSoundTouch->putSamples(buffer_back, iAvailFrames);
} else {
if (last_read_failed) {
m_pSoundTouch->flush();
break; // exit loop after failure
}
last_read_failed = true;
}
}
}
// framesRead is interpreted as the total number of virtual sample frames
// consumed to produce the scaled buffer. Due to this, we do not take into
// account directionality or starting point.
// NOTE(rryan): Why no m_dPitchAdjust here? SoundTouch implements pitch
// shifting as a tempo shift of (1/m_dPitchAdjust) and a rate shift of
// (*m_dPitchAdjust) so these two cancel out.
double framesRead = m_dBaseRate * m_dTempoRatio * total_received_frames;
return framesRead;
}
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