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/* -*- 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 */
#ifndef AudioBuffer_h_
#define AudioBuffer_h_
#include "AudioSegment.h"
#include "nsWrapperCache.h"
#include "nsCycleCollectionParticipant.h"
#include "mozilla/Attributes.h"
#include "mozilla/StaticPtr.h"
#include "mozilla/StaticMutex.h"
#include "nsTArray.h"
#include "js/TypeDecls.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/dom/TypedArray.h"
#include "nsPIDOMWindow.h"
#include "nsIWeakReferenceUtils.h"
namespace mozilla {
class ErrorResult;
class ThreadSharedFloatArrayBufferList;
namespace dom {
struct AudioBufferOptions;
* An AudioBuffer keeps its data either in the mJSChannels objects, which
* are Float32Arrays, or in mSharedChannels if the mJSChannels objects' buffers
* are detached.
class AudioBuffer final : public nsWrapperCache {
// If non-null, aInitialContents must have number of channels equal to
// aNumberOfChannels and their lengths must be at least aLength.
static already_AddRefed<AudioBuffer> Create(
nsPIDOMWindowInner* aWindow, uint32_t aNumberOfChannels, uint32_t aLength,
float aSampleRate,
already_AddRefed<ThreadSharedFloatArrayBufferList> aInitialContents,
ErrorResult& aRv);
static already_AddRefed<AudioBuffer> Create(nsPIDOMWindowInner* aWindow,
uint32_t aNumberOfChannels,
uint32_t aLength,
float aSampleRate,
ErrorResult& aRv) {
return Create(aWindow, aNumberOfChannels, aLength, aSampleRate, nullptr,
// Non-unit AudioChunk::mVolume is not supported
static already_AddRefed<AudioBuffer> Create(nsPIDOMWindowInner* aWindow,
float aSampleRate,
AudioChunk&& aInitialContents);
size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
static already_AddRefed<AudioBuffer> Constructor(
const GlobalObject& aGlobal, const AudioBufferOptions& aOptions,
ErrorResult& aRv);
nsPIDOMWindowInner* GetParentObject() const {
nsCOMPtr<nsPIDOMWindowInner> parentObject = do_QueryReferent(mOwnerWindow);
return parentObject;
JSObject* WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) override;
float SampleRate() const { return mSampleRate; }
uint32_t Length() const { return mSharedChannels.mDuration; }
double Duration() const {
return Length() / static_cast<double>(mSampleRate);
uint32_t NumberOfChannels() const { return mJSChannels.Length(); }
* If mSharedChannels is non-null, copies its contents to
* new Float32Arrays in mJSChannels. Returns a Float32Array.
void GetChannelData(JSContext* aJSContext, uint32_t aChannel,
JS::MutableHandle<JSObject*> aRetval, ErrorResult& aRv);
void CopyFromChannel(const Float32Array& aDestination,
uint32_t aChannelNumber, uint32_t aBufferOffset,
ErrorResult& aRv);
void CopyToChannel(JSContext* aJSContext, const Float32Array& aSource,
uint32_t aChannelNumber, uint32_t aBufferOffset,
ErrorResult& aRv);
* Returns a reference to an AudioChunk containing the sample data.
* The AudioChunk can have a null buffer if there is no data.
const AudioChunk& GetThreadSharedChannelsForRate(JSContext* aContext);
AudioBuffer(nsPIDOMWindowInner* aWindow, uint32_t aNumberOfChannels,
uint32_t aLength, float aSampleRate, ErrorResult& aRv);
void SetSharedChannels(
already_AddRefed<ThreadSharedFloatArrayBufferList> aBuffer);
bool RestoreJSChannelData(JSContext* aJSContext);
StealJSArrayDataIntoSharedChannels(JSContext* aJSContext);
void ClearJSChannels();
// Float32Arrays
AutoTArray<JS::Heap<JSObject*>, 2> mJSChannels;
// mSharedChannels aggregates the data from mJSChannels. This is non-null
// if and only if the mJSChannels' buffers are detached, but its mDuration
// member keeps the buffer length regardless of whether the buffer is
// provided by mJSChannels or mSharedChannels.
AudioChunk mSharedChannels;
nsWeakPtr mOwnerWindow;
float mSampleRate;
} // namespace dom
} // namespace mozilla