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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 */
#include "mozilla/Mutex.h"
#include "mozilla/TimeStamp.h"
#include "gfxPoint.h"
#include "nsCOMPtr.h"
#include "ImageContainer.h"
#include "MediaSegment.h"
#include "VideoSegment.h"
namespace mozilla {
class MediaDecoderOwner;
* This object is used in the decoder backend threads and the main thread
* to manage the "current video frame" state. This state includes timing data
* and an intrinsic size (see below).
* This has to be a thread-safe object since it's accessed by resource decoders
* and other off-main-thread components. So we can't put this state in the media
* element itself ... well, maybe we could, but it could be risky and/or
* confusing.
class VideoFrameContainer {
virtual ~VideoFrameContainer();
typedef layers::ImageContainer ImageContainer;
typedef layers::Image Image;
VideoFrameContainer(MediaDecoderOwner* aOwner,
already_AddRefed<ImageContainer> aContainer);
void SetCurrentFrame(const gfx::IntSize& aIntrinsicSize, Image* aImage,
const TimeStamp& aTargetTime);
// Returns the last principalHandle we notified mElement about.
PrincipalHandle GetLastPrincipalHandle();
PrincipalHandle GetLastPrincipalHandleLocked() MOZ_REQUIRES(mMutex);
// We will notify mElement that aPrincipalHandle has been applied when all
// FrameIDs prior to aFrameID have been flushed out.
// aFrameID is ignored if aPrincipalHandle already is our pending
// principalHandle.
void UpdatePrincipalHandleForFrameID(const PrincipalHandle& aPrincipalHandle,
const ImageContainer::FrameID& aFrameID);
void UpdatePrincipalHandleForFrameIDLocked(
const PrincipalHandle& aPrincipalHandle,
const ImageContainer::FrameID& aFrameID) MOZ_REQUIRES(mMutex);
void SetCurrentFrames(
const gfx::IntSize& aIntrinsicSize,
const nsTArray<ImageContainer::NonOwningImage>& aImages);
void ClearCurrentFrame(const gfx::IntSize& aIntrinsicSize) {
// Make the current frame the only frame in the container, i.e. discard
// all future frames.
void ClearFutureFrames(TimeStamp aNow = TimeStamp::Now());
// Time in seconds by which the last painted video frame was late by.
// E.g. if the last painted frame should have been painted at time t,
// but was actually painted at t+n, this returns n in seconds. Threadsafe.
double GetFrameDelay();
// Clear any resources that are not immediately necessary.
void ClearCachedResources();
// Returns a new frame ID for SetCurrentFrames(). The client must either
// call this on only one thread or provide barriers. Do not use together
// with SetCurrentFrame().
ImageContainer::FrameID NewFrameID() { return ++mFrameID; }
// Call on main thread
void Invalidate() { InvalidateWithFlags(INVALIDATE_DEFAULT); }
void InvalidateWithFlags(uint32_t aFlags);
ImageContainer* GetImageContainer();
void ForgetElement() { mOwner = nullptr; }
uint32_t GetDroppedImageCount() {
MutexAutoLock lock(mMutex);
return mImageContainer->GetDroppedImageCount();
Maybe<gfx::IntSize> CurrentIntrinsicSize() {
MutexAutoLock lock(mMutex);
return mIntrinsicSize;
void SetCurrentFramesLocked(
const gfx::IntSize& aIntrinsicSize,
const nsTArray<ImageContainer::NonOwningImage>& aImages)
// Non-addreffed pointer to the owner. The owner calls ForgetElement
// to clear this reference when the owner is destroyed.
MediaDecoderOwner* mOwner;
RefPtr<ImageContainer> mImageContainer;
struct {
// True when the Image size has changed since the last time Invalidate() was
// called. When set, the next call to Invalidate() will ensure that the
// frame is fully invalidated instead of just invalidating for the image
// change in the ImageLayer.
bool mImageSizeChanged = false;
// The main thread mirror of the member of the same name below, in case it
// has changed.
// Set to some size when the intrinsic size has been changed by
// SetCurrentFrame() since the last call to Invalidate().
// The next call to Invalidate() will recalculate and update the intrinsic
// size on the element, request a frame reflow and then reset this to
// Nothing.
Maybe<gfx::IntSize> mNewIntrinsicSize;
} mMainThreadState;
Mutex mMutex;
// The intrinsic size is the ideal size which we should render the
// ImageContainer's current Image at.
// This can differ from the Image's actual size when the media resource
// specifies that the Image should be stretched to have the correct aspect
// ratio.
Maybe<gfx::IntSize> mIntrinsicSize MOZ_GUARDED_BY(mMutex);
// We maintain our own mFrameID which is auto-incremented at every
// SetCurrentFrame() or NewFrameID() call.
ImageContainer::FrameID mFrameID;
// The last PrincipalHandle we notified mElement about.
PrincipalHandle mLastPrincipalHandle MOZ_GUARDED_BY(mMutex);
// The PrincipalHandle the client has notified us is changing with FrameID
// mFrameIDForPendingPrincipalHandle.
PrincipalHandle mPendingPrincipalHandle MOZ_GUARDED_BY(mMutex);
// The FrameID for which mPendingPrincipal is first valid.
ImageContainer::FrameID mFrameIDForPendingPrincipalHandle
const RefPtr<AbstractThread> mMainThread;
} // namespace mozilla