gecko/content/media/MediaRecorder.h

128 lines
5.2 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/. */
#ifndef MediaRecorder_h
#define MediaRecorder_h
#include "DOMMediaStream.h"
#include "MediaEncoder.h"
#include "mozilla/dom/MediaRecorderBinding.h"
#include "nsDOMEventTargetHelper.h"
#include "EncodedBufferCache.h"
#include "TrackUnionStream.h"
// Max size for allowing queue encoded data in memory
#define MAX_ALLOW_MEMORY_BUFFER 1024000
namespace mozilla {
class ErrorResult;
namespace dom {
/**
* Implementation of https://dvcs.w3.org/hg/dap/raw-file/default/media-stream-capture/MediaRecorder.html
* The MediaRecorder accepts a mediaStream as input source passed from UA. When recorder starts,
* a MediaEncoder will be created and accept the mediaStream as input source.
* Encoder will get the raw data by track data changes, encode it by selected MIME Type, then store the encoded in EncodedBufferCache object.
* The encoded data will be extracted on every timeslice passed from Start function call or by RequestData function.
* Thread model:
* When the recorder starts, it creates a "Media Encoder" thread to read data from MediaEncoder object and store buffer in EncodedBufferCache object.
* Also extract the encoded data and create blobs on every timeslice passed from start function or RequestData function called by UA.
*/
class MediaRecorder : public nsDOMEventTargetHelper
{
class ExtractEncodedDataTask;
class PushBlobTask;
class PushErrorMessageTask;
public:
MediaRecorder(DOMMediaStream&);
virtual ~MediaRecorder();
// nsWrapperCache
virtual JSObject* WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aScope) MOZ_OVERRIDE;
nsPIDOMWindow* GetParentObject() { return GetOwner(); }
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(MediaRecorder,
nsDOMEventTargetHelper)
// WebIDL
// Start recording. If timeSlice has been provided, mediaRecorder will
// raise a dataavailable event containing the Blob of collected data on every timeSlice milliseconds.
// If timeSlice isn't provided, UA should call the RequestData to obtain the Blob data, also set the mTimeSlice to zero.
void Start(const Optional<int32_t>& timeSlice, ErrorResult & aResult);
// Stop the recording activiy. Including stop the Media Encoder thread, un-hook the mediaStreamListener to encoder.
void Stop(ErrorResult& aResult);
// Pause the mTrackUnionStream
void Pause(ErrorResult& aResult);
void Resume(ErrorResult& aResult);
// Extract encoded data Blob from EncodedBufferCache.
void RequestData(ErrorResult& aResult);
// Return the The DOMMediaStream passed from UA.
DOMMediaStream* Stream() const { return mStream; }
// The current state of the MediaRecorder object.
RecordingState State() const { return mState; }
// Return the current encoding MIME type selected by the MediaEncoder.
void GetMimeType(nsString &aMimeType) { aMimeType = mMimeType; }
static already_AddRefed<MediaRecorder>
Constructor(const GlobalObject& aGlobal, JSContext* aCx, DOMMediaStream& aStream,
ErrorResult& aRv);
// EventHandler
IMPL_EVENT_HANDLER(dataavailable)
IMPL_EVENT_HANDLER(error)
IMPL_EVENT_HANDLER(stop)
IMPL_EVENT_HANDLER(warning)
friend class ExtractEncodedData;
protected:
void Init(JSContext* aCx, nsPIDOMWindow* aOwnerWindow);
// Copy encoded data from encoder to EncodedBufferCache. This function runs in the Media Encoder Thread.
void ExtractEncodedData();
MediaRecorder& operator = (const MediaRecorder& x) MOZ_DELETE;
// Create dataavailable event with Blob data and it runs in main thread
nsresult CreateAndDispatchBlobEvent();
// Creating a simple event to notify UA simple event.
void DispatchSimpleEvent(const nsAString & aStr);
// Creating a error event with message.
void NotifyError(nsresult aRv);
// Check if the recorder's principal is the subsume of mediaStream
bool CheckPrincipal();
MediaRecorder(const MediaRecorder& x) MOZ_DELETE; // prevent bad usage
// Runnable thread for read data from mediaEncoder. It starts at MediaRecorder::Start() and stops at MediaRecorder::Stop().
nsCOMPtr<nsIThread> mReadThread;
// The MediaEncoder object initializes on start() and destroys in ~MediaRecorder.
nsRefPtr<MediaEncoder> mEncoder;
// MediaStream passed from js context
nsRefPtr<DOMMediaStream> mStream;
// This media stream is used for notifying raw data to encoder and can be blocked.
nsRefPtr<ProcessedMediaStream> mTrackUnionStream;
// This object creates on start() and destroys in ~MediaRecorder.
nsAutoPtr<EncodedBufferCache> mEncodedBufferCache;
// It specifies the container format as well as the audio and video capture formats.
nsString mMimeType;
// The interval of timer passed from Start(). On every mTimeSlice milliseconds, if there are buffers store in the EncodedBufferCache,
// a dataavailable event will be fired.
int32_t mTimeSlice;
// The current state of the MediaRecorder object.
RecordingState mState;
};
}
}
#endif