gecko-dev/dom/media/AbstractMediaDecoder.h

123 строки
3.9 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 AbstractMediaDecoder_h_
#define AbstractMediaDecoder_h_
#include "mozilla/Attributes.h"
#include "mozilla/StateMirroring.h"
#include "MediaEventSource.h"
#include "MediaInfo.h"
#include "nsISupports.h"
#include "nsDataHashtable.h"
#include "nsThreadUtils.h"
namespace mozilla
{
namespace layers
{
class ImageContainer;
} // namespace layers
class MediaResource;
class ReentrantMonitor;
class VideoFrameContainer;
class MediaDecoderOwner;
#ifdef MOZ_EME
class CDMProxy;
#endif
typedef nsDataHashtable<nsCStringHashKey, nsCString> MetadataTags;
static inline bool IsCurrentThread(nsIThread* aThread) {
return NS_GetCurrentThread() == aThread;
}
/**
* The AbstractMediaDecoder class describes the public interface for a media decoder
* and is used by the MediaReader classes.
*/
class AbstractMediaDecoder : public nsIObserver
{
public:
// A special version of the above for the ogg decoder that is allowed to be
// called cross-thread.
virtual bool IsOggDecoderShutdown() { return false; }
// Get the current MediaResource being used. Its URI will be returned
// by currentSrc. Returns what was passed to Load(), if Load() has been called.
virtual MediaResource* GetResource() const = 0;
// Increments the parsed, decoded and dropped frame counters by the passed in
// counts.
// Can be called on any thread.
virtual void NotifyDecodedFrames(uint32_t aParsed, uint32_t aDecoded,
uint32_t aDropped) = 0;
virtual AbstractCanonical<media::NullableTimeUnit>* CanonicalDurationOrNull() { return nullptr; };
// Return an event that will be notified when data arrives in MediaResource.
// MediaDecoderReader will register with this event to receive notifications
// in order to udpate buffer ranges.
// Return null if this decoder doesn't support the event.
virtual MediaEventSource<void>* DataArrivedEvent()
{
return nullptr;
}
protected:
virtual void UpdateEstimatedMediaDuration(int64_t aDuration) {};
public:
void DispatchUpdateEstimatedMediaDuration(int64_t aDuration)
{
nsCOMPtr<nsIRunnable> r =
NS_NewRunnableMethodWithArg<int64_t>(this, &AbstractMediaDecoder::UpdateEstimatedMediaDuration,
aDuration);
NS_DispatchToMainThread(r);
}
virtual VideoFrameContainer* GetVideoFrameContainer() = 0;
virtual mozilla::layers::ImageContainer* GetImageContainer() = 0;
// Returns the owner of this media decoder. The owner should only be used
// on the main thread.
virtual MediaDecoderOwner* GetOwner() = 0;
// Set by Reader if the current audio track can be offloaded
virtual void SetPlatformCanOffloadAudio(bool aCanOffloadAudio) {}
// Stack based class to assist in notifying the frame statistics of
// parsed and decoded frames. Use inside video demux & decode functions
// to ensure all parsed and decoded frames are reported on all return paths.
class AutoNotifyDecoded {
public:
explicit AutoNotifyDecoded(AbstractMediaDecoder* aDecoder)
: mParsed(0), mDecoded(0), mDropped(0), mDecoder(aDecoder) {}
~AutoNotifyDecoded() {
if (mDecoder) {
mDecoder->NotifyDecodedFrames(mParsed, mDecoded, mDropped);
}
}
uint32_t mParsed;
uint32_t mDecoded;
uint32_t mDropped;
private:
AbstractMediaDecoder* mDecoder;
};
// Classes directly inheriting from AbstractMediaDecoder do not support
// Observe and it should never be called directly.
NS_IMETHOD Observe(nsISupports *aSubject, const char * aTopic, const char16_t * aData) override
{ MOZ_CRASH("Forbidden method"); return NS_OK; }
};
} // namespace mozilla
#endif