gecko/content/media/VideoSegment.h
Robert O'Callahan d76ff3d562 Bug 664918. Part 2: Create MediaSegment, AudioSegment and VideoSegment classes to manage intervals of media data. r=jesup
Also introduces a SharedBuffer class, representing a blob of binary data with threadsafe refcounting.
2012-04-30 15:11:19 +12:00

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3.2 KiB
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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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 MOZILLA_VIDEOSEGMENT_H_
#define MOZILLA_VIDEOSEGMENT_H_
#include "MediaSegment.h"
#include "ImageLayers.h"
namespace mozilla {
class VideoFrame {
public:
typedef mozilla::layers::Image Image;
VideoFrame(already_AddRefed<Image> aImage, const gfxIntSize& aIntrinsicSize)
: mImage(aImage), mIntrinsicSize(aIntrinsicSize) {}
VideoFrame() : mIntrinsicSize(0, 0) {}
bool operator==(const VideoFrame& aFrame) const
{
return mImage == aFrame.mImage && mIntrinsicSize == aFrame.mIntrinsicSize;
}
bool operator!=(const VideoFrame& aFrame) const
{
return !operator==(aFrame);
}
Image* GetImage() const { return mImage; }
const gfxIntSize& GetIntrinsicSize() const { return mIntrinsicSize; }
void SetNull() { mImage = nsnull; mIntrinsicSize = gfxIntSize(0, 0); }
void TakeFrom(VideoFrame* aFrame)
{
mImage = aFrame->mImage.forget();
mIntrinsicSize = aFrame->mIntrinsicSize;
}
protected:
// mImage can be null to indicate "no video" (aka "empty frame"). It can
// still have an intrinsic size in this case.
nsRefPtr<Image> mImage;
// The desired size to render the video frame at.
gfxIntSize mIntrinsicSize;
};
struct VideoChunk {
void SliceTo(TrackTicks aStart, TrackTicks aEnd)
{
NS_ASSERTION(aStart >= 0 && aStart < aEnd && aEnd <= mDuration,
"Slice out of bounds");
mDuration = aEnd - aStart;
}
TrackTicks GetDuration() const { return mDuration; }
bool CanCombineWithFollowing(const VideoChunk& aOther) const
{
return aOther.mFrame == mFrame;
}
bool IsNull() const { return !mFrame.GetImage(); }
void SetNull(TrackTicks aDuration)
{
mDuration = aDuration;
mFrame.SetNull();
}
TrackTicks mDuration;
VideoFrame mFrame;
};
class VideoSegment : public MediaSegmentBase<VideoSegment, VideoChunk> {
public:
typedef mozilla::layers::Image Image;
VideoSegment() : MediaSegmentBase<VideoSegment, VideoChunk>(VIDEO) {}
void AppendFrame(already_AddRefed<Image> aImage, TrackTicks aDuration,
const gfxIntSize& aIntrinsicSize)
{
VideoChunk* chunk = AppendChunk(aDuration);
VideoFrame frame(aImage, aIntrinsicSize);
chunk->mFrame.TakeFrom(&frame);
}
const VideoFrame* GetFrameAt(TrackTicks aOffset, TrackTicks* aStart = nsnull)
{
VideoChunk* c = FindChunkContaining(aOffset, aStart);
if (!c) {
return nsnull;
}
return &c->mFrame;
}
const VideoFrame* GetLastFrame(TrackTicks* aStart = nsnull)
{
VideoChunk* c = GetLastChunk();
if (!c) {
return nsnull;
}
if (aStart) {
*aStart = mDuration - c->mDuration;
}
return &c->mFrame;
}
// Segment-generic methods not in MediaSegmentBase
void InitFrom(const VideoSegment& aOther)
{
}
void SliceFrom(const VideoSegment& aOther, TrackTicks aStart, TrackTicks aEnd) {
BaseSliceFrom(aOther, aStart, aEnd);
}
static Type StaticType() { return VIDEO; }
};
}
#endif /* MOZILLA_VIDEOSEGMENT_H_ */