gecko-dev/dom/media/webaudio/OscillatorNode.cpp

703 lines
21 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "OscillatorNode.h"
#include "AudioNodeEngine.h"
#include "AudioNodeStream.h"
#include "AudioDestinationNode.h"
#include "WebAudioUtils.h"
#include "blink/PeriodicWave.h"
namespace mozilla {
namespace dom {
NS_IMPL_CYCLE_COLLECTION_INHERITED(OscillatorNode, AudioNode,
mPeriodicWave, mFrequency, mDetune)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(OscillatorNode)
NS_INTERFACE_MAP_END_INHERITING(AudioNode)
NS_IMPL_ADDREF_INHERITED(OscillatorNode, AudioNode)
NS_IMPL_RELEASE_INHERITED(OscillatorNode, AudioNode)
static const float sLeakTriangle = 0.995f;
static const float sLeak = 0.999f;
class DCBlocker
{
public:
// These are sane defauts when the initial mPhase is zero
explicit DCBlocker(float aLastInput = 0.0f,
float aLastOutput = 0.0f,
float aPole = 0.995)
:mLastInput(aLastInput),
mLastOutput(aLastOutput),
mPole(aPole)
{
MOZ_ASSERT(aPole > 0);
}
inline float Process(float aInput)
{
float out;
out = mLastOutput * mPole + aInput - mLastInput;
mLastOutput = out;
mLastInput = aInput;
return out;
}
private:
float mLastInput;
float mLastOutput;
float mPole;
};
class OscillatorNodeEngine : public AudioNodeEngine
{
public:
OscillatorNodeEngine(AudioNode* aNode, AudioDestinationNode* aDestination)
: AudioNodeEngine(aNode)
, mSource(nullptr)
, mDestination(static_cast<AudioNodeStream*> (aDestination->Stream()))
, mStart(-1)
, mStop(STREAM_TIME_MAX)
// Keep the default values in sync with OscillatorNode::OscillatorNode.
, mFrequency(440.f)
, mDetune(0.f)
, mType(OscillatorType::Sine)
, mPhase(0.)
// mSquare, mTriangle, and mSaw are not used for default type "sine".
// They are initialized if and when switching to the OscillatorTypes that
// use them.
// mFinalFrequency, mNumberOfHarmonics, mSignalPeriod, mAmplitudeAtZero,
// mPhaseIncrement, and mPhaseWrap are initialized in
// UpdateParametersIfNeeded() when mRecomputeParameters is set.
, mRecomputeParameters(true)
, mCustomLength(0)
{
}
void SetSourceStream(AudioNodeStream* aSource)
{
mSource = aSource;
}
enum Parameters {
FREQUENCY,
DETUNE,
TYPE,
PERIODICWAVE,
START,
STOP,
};
void SetTimelineParameter(uint32_t aIndex,
const AudioParamTimeline& aValue,
TrackRate aSampleRate) MOZ_OVERRIDE
{
mRecomputeParameters = true;
switch (aIndex) {
case FREQUENCY:
MOZ_ASSERT(mSource && mDestination);
mFrequency = aValue;
WebAudioUtils::ConvertAudioParamToTicks(mFrequency, mSource, mDestination);
break;
case DETUNE:
MOZ_ASSERT(mSource && mDestination);
mDetune = aValue;
WebAudioUtils::ConvertAudioParamToTicks(mDetune, mSource, mDestination);
break;
default:
NS_ERROR("Bad OscillatorNodeEngine TimelineParameter");
}
}
virtual void SetStreamTimeParameter(uint32_t aIndex, StreamTime aParam)
{
switch (aIndex) {
case START: mStart = aParam; break;
case STOP: mStop = aParam; break;
default:
NS_ERROR("Bad OscillatorNodeEngine StreamTimeParameter");
}
}
virtual void SetInt32Parameter(uint32_t aIndex, int32_t aParam)
{
switch (aIndex) {
case TYPE:
// Set the new type.
mType = static_cast<OscillatorType>(aParam);
if (mType != OscillatorType::Custom) {
// Forget any previous custom data.
mCustomLength = 0;
mCustom = nullptr;
mPeriodicWave = nullptr;
mRecomputeParameters = true;
}
// Update BLIT integrators with the new initial conditions.
switch (mType) {
case OscillatorType::Sine:
mPhase = 0.0;
break;
case OscillatorType::Square:
mPhase = 0.0;
// Initial integration condition is -0.5, because our
// square has 50% duty cycle.
mSquare = -0.5;
break;
case OscillatorType::Triangle:
// Initial mPhase and related integration condition so the
// triangle is in the middle of the first upward slope.
// XXX actually do the maths and put the right number here.
mPhase = (float)(M_PI / 2);
mSquare = 0.5;
mTriangle = 0.0;
break;
case OscillatorType::Sawtooth:
// Initial mPhase so the oscillator starts at the
// middle of the ramp, per spec.
mPhase = (float)(M_PI / 2);
// mSaw = 0 when mPhase = pi/2.
mSaw = 0.0;
break;
case OscillatorType::Custom:
// Custom waveforms don't use BLIT.
break;
default:
NS_ERROR("Bad OscillatorNodeEngine type parameter.");
}
// End type switch.
break;
case PERIODICWAVE:
MOZ_ASSERT(aParam >= 0, "negative custom array length");
mCustomLength = static_cast<uint32_t>(aParam);
break;
default:
NS_ERROR("Bad OscillatorNodeEngine Int32Parameter.");
}
// End index switch.
}
virtual void SetBuffer(already_AddRefed<ThreadSharedFloatArrayBufferList> aBuffer)
{
MOZ_ASSERT(mCustomLength, "Custom buffer sent before length");
mCustom = aBuffer;
MOZ_ASSERT(mCustom->GetChannels() == 2,
"PeriodicWave should have sent two channels");
mPeriodicWave = WebCore::PeriodicWave::create(mSource->SampleRate(),
mCustom->GetData(0), mCustom->GetData(1), mCustomLength);
}
void IncrementPhase()
{
mPhase += mPhaseIncrement;
if (mPhase > mPhaseWrap) {
mPhase -= mPhaseWrap;
}
}
// Square and triangle are using a bipolar band-limited impulse train, saw is
// using a normal band-limited impulse train.
bool UsesBipolarBLIT() {
return mType == OscillatorType::Square || mType == OscillatorType::Triangle;
}
void UpdateParametersIfNeeded(StreamTime ticks, size_t count)
{
double frequency, detune;
bool simpleFrequency = mFrequency.HasSimpleValue();
bool simpleDetune = mDetune.HasSimpleValue();
// Shortcut if frequency-related AudioParam are not automated, and we
// already have computed the frequency information and related parameters.
if (simpleFrequency && simpleDetune && !mRecomputeParameters) {
return;
}
if (simpleFrequency) {
frequency = mFrequency.GetValue();
} else {
frequency = mFrequency.GetValueAtTime(ticks, count);
}
if (simpleDetune) {
detune = mDetune.GetValue();
} else {
detune = mDetune.GetValueAtTime(ticks, count);
}
mFinalFrequency = frequency * pow(2., detune / 1200.);
mRecomputeParameters = false;
// When using bipolar BLIT, we divide the signal period by two, because we
// are using two BLIT out of phase.
mSignalPeriod = UsesBipolarBLIT() ? 0.5 * mSource->SampleRate() / mFinalFrequency
: mSource->SampleRate() / mFinalFrequency;
// Wrap the phase accordingly:
mPhaseWrap = UsesBipolarBLIT() || mType == OscillatorType::Sine ? 2 * M_PI
: M_PI;
// Even number of harmonics for bipolar blit, odd otherwise.
mNumberOfHarmonics = UsesBipolarBLIT() ? 2 * floor(0.5 * mSignalPeriod)
: 2 * floor(0.5 * mSignalPeriod) + 1;
mPhaseIncrement = mType == OscillatorType::Sine ? 2 * M_PI / mSignalPeriod
: M_PI / mSignalPeriod;
mAmplitudeAtZero = mNumberOfHarmonics / mSignalPeriod;
}
void FillBounds(float* output, StreamTime ticks,
uint32_t& start, uint32_t& end)
{
MOZ_ASSERT(output);
static_assert(StreamTime(WEBAUDIO_BLOCK_SIZE) < UINT_MAX,
"WEBAUDIO_BLOCK_SIZE overflows interator bounds.");
start = 0;
if (ticks < mStart) {
start = mStart - ticks;
for (uint32_t i = 0; i < start; ++i) {
output[i] = 0.0;
}
}
end = WEBAUDIO_BLOCK_SIZE;
if (ticks + end > mStop) {
end = mStop - ticks;
for (uint32_t i = end; i < WEBAUDIO_BLOCK_SIZE; ++i) {
output[i] = 0.0;
}
}
}
float BipolarBLIT()
{
float blit;
float denom = sin(mPhase);
if (fabs(denom) < std::numeric_limits<float>::epsilon()) {
if (mPhase < 0.1f || mPhase > 2 * M_PI - 0.1f) {
blit = mAmplitudeAtZero;
} else {
blit = -mAmplitudeAtZero;
}
} else {
blit = sin(mNumberOfHarmonics * mPhase);
blit /= mSignalPeriod * denom;
}
return blit;
}
float UnipolarBLIT()
{
float blit;
float denom = sin(mPhase);
if (fabs(denom) <= std::numeric_limits<float>::epsilon()) {
blit = mAmplitudeAtZero;
} else {
blit = sin(mNumberOfHarmonics * mPhase);
blit /= mSignalPeriod * denom;
}
return blit;
}
void ComputeSine(float * aOutput, StreamTime ticks, uint32_t aStart, uint32_t aEnd)
{
for (uint32_t i = aStart; i < aEnd; ++i) {
UpdateParametersIfNeeded(ticks, i);
aOutput[i] = sin(mPhase);
IncrementPhase();
}
}
void ComputeSquare(float * aOutput, StreamTime ticks, uint32_t aStart, uint32_t aEnd)
{
for (uint32_t i = aStart; i < aEnd; ++i) {
UpdateParametersIfNeeded(ticks, i);
// Integration to get us a square. It turns out we can have a
// pure integrator here.
mSquare = mSquare * sLeak + BipolarBLIT();
aOutput[i] = mSquare;
// maybe we want to apply a gain, the wg has not decided yet
aOutput[i] *= 1.5;
IncrementPhase();
}
}
void ComputeSawtooth(float * aOutput, StreamTime ticks, uint32_t aStart, uint32_t aEnd)
{
float dcoffset;
for (uint32_t i = aStart; i < aEnd; ++i) {
UpdateParametersIfNeeded(ticks, i);
// DC offset so the Saw does not ramp up to infinity when integrating.
dcoffset = mFinalFrequency / mSource->SampleRate();
// Integrate and offset so we get mAmplitudeAtZero sawtooth. We have a
// very low frequency component somewhere here, but I'm not sure where.
mSaw = mSaw * sLeak + (UnipolarBLIT() - dcoffset);
// reverse the saw so we are spec compliant
aOutput[i] = -mSaw * 1.5;
IncrementPhase();
}
}
void ComputeTriangle(float * aOutput, StreamTime ticks, uint32_t aStart, uint32_t aEnd)
{
for (uint32_t i = aStart; i < aEnd; ++i) {
UpdateParametersIfNeeded(ticks, i);
// Integrate to get a square
mSquare += BipolarBLIT();
// Leaky integrate to get a triangle. We get too much dc offset if we don't
// leaky integrate here.
// C6 = k0 / period
// (period is samplingrate / frequency, k0 = (PI/2)/(2*PI)) = 0.25
float C6 = 0.25 / (mSource->SampleRate() / mFinalFrequency);
mTriangle = mTriangle * sLeakTriangle + mSquare + C6;
// DC Block, and scale back to [-1.0; 1.0]
aOutput[i] = mDCBlocker.Process(mTriangle) / (mSignalPeriod/2) * 1.5;
IncrementPhase();
}
}
void ComputeCustom(float* aOutput,
StreamTime ticks,
uint32_t aStart,
uint32_t aEnd)
{
MOZ_ASSERT(mPeriodicWave, "No custom waveform data");
uint32_t periodicWaveSize = mPeriodicWave->periodicWaveSize();
// Mask to wrap wave data indices into the range [0,periodicWaveSize).
uint32_t indexMask = periodicWaveSize - 1;
MOZ_ASSERT(periodicWaveSize && (periodicWaveSize & indexMask) == 0,
"periodicWaveSize must be power of 2");
float* higherWaveData = nullptr;
float* lowerWaveData = nullptr;
float tableInterpolationFactor;
// Phase increment at frequency of 1 Hz.
// mPhase runs [0,periodicWaveSize) here instead of [0,2*M_PI).
float basePhaseIncrement =
static_cast<float>(periodicWaveSize) / mSource->SampleRate();
for (uint32_t i = aStart; i < aEnd; ++i) {
UpdateParametersIfNeeded(ticks, i);
mPeriodicWave->waveDataForFundamentalFrequency(mFinalFrequency,
lowerWaveData,
higherWaveData,
tableInterpolationFactor);
// Bilinear interpolation between adjacent samples in each table.
float floorPhase = floorf(mPhase);
uint32_t j1 = floorPhase;
j1 &= indexMask;
uint32_t j2 = j1 + 1;
j2 &= indexMask;
float sampleInterpolationFactor = mPhase - floorPhase;
float lower = (1.0f - sampleInterpolationFactor) * lowerWaveData[j1] +
sampleInterpolationFactor * lowerWaveData[j2];
float higher = (1.0f - sampleInterpolationFactor) * higherWaveData[j1] +
sampleInterpolationFactor * higherWaveData[j2];
aOutput[i] = (1.0f - tableInterpolationFactor) * lower +
tableInterpolationFactor * higher;
// Calculate next phase position from wrapped value j1 to avoid loss of
// precision at large values.
mPhase =
j1 + sampleInterpolationFactor + basePhaseIncrement * mFinalFrequency;
}
}
void ComputeSilence(AudioChunk *aOutput)
{
aOutput->SetNull(WEBAUDIO_BLOCK_SIZE);
}
virtual void ProcessBlock(AudioNodeStream* aStream,
const AudioChunk& aInput,
AudioChunk* aOutput,
bool* aFinished) MOZ_OVERRIDE
{
MOZ_ASSERT(mSource == aStream, "Invalid source stream");
StreamTime ticks = aStream->GetCurrentPosition();
if (mStart == -1) {
ComputeSilence(aOutput);
return;
}
if (ticks >= mStop) {
// We've finished playing.
ComputeSilence(aOutput);
*aFinished = true;
return;
}
if (ticks + WEBAUDIO_BLOCK_SIZE < mStart) {
// We're not playing yet.
ComputeSilence(aOutput);
return;
}
AllocateAudioBlock(1, aOutput);
float* output = static_cast<float*>(
const_cast<void*>(aOutput->mChannelData[0]));
uint32_t start, end;
FillBounds(output, ticks, start, end);
// Synthesize the correct waveform.
switch(mType) {
case OscillatorType::Sine:
ComputeSine(output, ticks, start, end);
break;
case OscillatorType::Square:
ComputeSquare(output, ticks, start, end);
break;
case OscillatorType::Triangle:
ComputeTriangle(output, ticks, start, end);
break;
case OscillatorType::Sawtooth:
ComputeSawtooth(output, ticks, start, end);
break;
case OscillatorType::Custom:
ComputeCustom(output, ticks, start, end);
break;
default:
ComputeSilence(aOutput);
};
}
virtual size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const MOZ_OVERRIDE
{
size_t amount = AudioNodeEngine::SizeOfExcludingThis(aMallocSizeOf);
// Not owned:
// - mSource
// - mDestination
// - mFrequency (internal ref owned by node)
// - mDetune (internal ref owned by node)
if (mCustom) {
amount += mCustom->SizeOfIncludingThis(aMallocSizeOf);
}
if (mPeriodicWave) {
amount += mPeriodicWave->sizeOfIncludingThis(aMallocSizeOf);
}
return amount;
}
virtual size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const MOZ_OVERRIDE
{
return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
}
DCBlocker mDCBlocker;
AudioNodeStream* mSource;
AudioNodeStream* mDestination;
StreamTime mStart;
StreamTime mStop;
AudioParamTimeline mFrequency;
AudioParamTimeline mDetune;
OscillatorType mType;
float mPhase;
float mFinalFrequency;
uint32_t mNumberOfHarmonics;
float mSignalPeriod;
float mAmplitudeAtZero;
float mPhaseIncrement;
float mSquare;
float mTriangle;
float mSaw;
float mPhaseWrap;
bool mRecomputeParameters;
nsRefPtr<ThreadSharedFloatArrayBufferList> mCustom;
uint32_t mCustomLength;
nsAutoPtr<WebCore::PeriodicWave> mPeriodicWave;
};
OscillatorNode::OscillatorNode(AudioContext* aContext)
: AudioNode(aContext,
2,
ChannelCountMode::Max,
ChannelInterpretation::Speakers)
, mType(OscillatorType::Sine)
, mFrequency(new AudioParam(MOZ_THIS_IN_INITIALIZER_LIST(),
SendFrequencyToStream, 440.0f))
, mDetune(new AudioParam(MOZ_THIS_IN_INITIALIZER_LIST(),
SendDetuneToStream, 0.0f))
, mStartCalled(false)
, mStopped(false)
{
OscillatorNodeEngine* engine = new OscillatorNodeEngine(this, aContext->Destination());
mStream = aContext->Graph()->CreateAudioNodeStream(engine, MediaStreamGraph::SOURCE_STREAM);
engine->SetSourceStream(static_cast<AudioNodeStream*> (mStream.get()));
mStream->AddMainThreadListener(this);
}
OscillatorNode::~OscillatorNode()
{
}
size_t
OscillatorNode::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
{
size_t amount = AudioNode::SizeOfExcludingThis(aMallocSizeOf);
// For now only report if we know for sure that it's not shared.
if (mPeriodicWave) {
amount += mPeriodicWave->SizeOfIncludingThisIfNotShared(aMallocSizeOf);
}
amount += mFrequency->SizeOfIncludingThis(aMallocSizeOf);
amount += mDetune->SizeOfIncludingThis(aMallocSizeOf);
return amount;
}
size_t
OscillatorNode::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const
{
return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
}
JSObject*
OscillatorNode::WrapObject(JSContext* aCx)
{
return OscillatorNodeBinding::Wrap(aCx, this);
}
void
OscillatorNode::SendFrequencyToStream(AudioNode* aNode)
{
OscillatorNode* This = static_cast<OscillatorNode*>(aNode);
SendTimelineParameterToStream(This, OscillatorNodeEngine::FREQUENCY, *This->mFrequency);
}
void
OscillatorNode::SendDetuneToStream(AudioNode* aNode)
{
OscillatorNode* This = static_cast<OscillatorNode*>(aNode);
SendTimelineParameterToStream(This, OscillatorNodeEngine::DETUNE, *This->mDetune);
}
void
OscillatorNode::SendTypeToStream()
{
if (mType == OscillatorType::Custom) {
// The engine assumes we'll send the custom data before updating the type.
SendPeriodicWaveToStream();
}
SendInt32ParameterToStream(OscillatorNodeEngine::TYPE, static_cast<int32_t>(mType));
}
void OscillatorNode::SendPeriodicWaveToStream()
{
NS_ASSERTION(mType == OscillatorType::Custom,
"Sending custom waveform to engine thread with non-custom type");
AudioNodeStream* ns = static_cast<AudioNodeStream*>(mStream.get());
MOZ_ASSERT(ns, "Missing node stream.");
MOZ_ASSERT(mPeriodicWave, "Send called without PeriodicWave object.");
SendInt32ParameterToStream(OscillatorNodeEngine::PERIODICWAVE,
mPeriodicWave->DataLength());
nsRefPtr<ThreadSharedFloatArrayBufferList> data =
mPeriodicWave->GetThreadSharedBuffer();
ns->SetBuffer(data.forget());
}
void
OscillatorNode::Start(double aWhen, ErrorResult& aRv)
{
if (!WebAudioUtils::IsTimeValid(aWhen)) {
aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
return;
}
if (mStartCalled) {
aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
return;
}
mStartCalled = true;
AudioNodeStream* ns = static_cast<AudioNodeStream*>(mStream.get());
if (!ns) {
// Nothing to play, or we're already dead for some reason
return;
}
// TODO: Perhaps we need to do more here.
ns->SetStreamTimeParameter(OscillatorNodeEngine::START,
Context(), aWhen);
MarkActive();
}
void
OscillatorNode::Stop(double aWhen, ErrorResult& aRv)
{
if (!WebAudioUtils::IsTimeValid(aWhen)) {
aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
return;
}
if (!mStartCalled) {
aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
return;
}
AudioNodeStream* ns = static_cast<AudioNodeStream*>(mStream.get());
if (!ns || !Context()) {
// We've already stopped and had our stream shut down
return;
}
// TODO: Perhaps we need to do more here.
ns->SetStreamTimeParameter(OscillatorNodeEngine::STOP,
Context(), std::max(0.0, aWhen));
}
void
OscillatorNode::NotifyMainThreadStateChanged()
{
if (mStream->IsFinished()) {
class EndedEventDispatcher : public nsRunnable
{
public:
explicit EndedEventDispatcher(OscillatorNode* aNode)
: mNode(aNode) {}
NS_IMETHODIMP Run()
{
// If it's not safe to run scripts right now, schedule this to run later
if (!nsContentUtils::IsSafeToRunScript()) {
nsContentUtils::AddScriptRunner(this);
return NS_OK;
}
mNode->DispatchTrustedEvent(NS_LITERAL_STRING("ended"));
return NS_OK;
}
private:
nsRefPtr<OscillatorNode> mNode;
};
if (!mStopped) {
// Only dispatch the ended event once
NS_DispatchToMainThread(new EndedEventDispatcher(this));
mStopped = true;
}
// Drop the playing reference
// Warning: The below line might delete this.
MarkInactive();
}
}
}
}