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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
#include "CaptureTask.h"
#include "gfxUtils.h"
#include "mozilla/dom/BlobImpl.h"
#include "mozilla/dom/ImageCapture.h"
#include "mozilla/dom/ImageCaptureError.h"
#include "mozilla/dom/ImageEncoder.h"
#include "mozilla/dom/MediaStreamTrack.h"
#include "mozilla/dom/VideoStreamTrack.h"
#include "mozilla/SchedulerGroup.h"
#include "nsThreadUtils.h"
#include "VideoSegment.h"
namespace mozilla {
class CaptureTask::MediaTrackEventListener : public MediaTrackListener {
public:
explicit MediaTrackEventListener(CaptureTask* aCaptureTask)
: mCaptureTask(aCaptureTask) {};
// MediaTrackListener methods.
void NotifyEnded(MediaTrackGraph* aGraph) override {
mCaptureTask->PostTrackEndEvent();
}
private:
CaptureTask* mCaptureTask;
};
CaptureTask::CaptureTask(dom::ImageCapture* aImageCapture)
: mImageCapture(aImageCapture),
mEventListener(new MediaTrackEventListener(this)),
mImageGrabbedOrTrackEnd(false),
mPrincipalChanged(false) {}
nsresult CaptureTask::TaskComplete(already_AddRefed<dom::BlobImpl> aBlobImpl,
nsresult aRv) {
MOZ_ASSERT(NS_IsMainThread());
DetachTrack();
nsresult rv;
RefPtr<dom::BlobImpl> blobImpl(aBlobImpl);
// We have to set the parent because the blob has been generated with a valid
// one.
RefPtr<dom::Blob> blob;
if (blobImpl) {
blob = dom::Blob::Create(mImageCapture->GetOwnerGlobal(), blobImpl);
if (NS_WARN_IF(!blob)) {
return NS_ERROR_FAILURE;
}
}
if (mPrincipalChanged) {
aRv = NS_ERROR_DOM_SECURITY_ERR;
IC_LOG("MediaStream principal should not change during TakePhoto().");
}
if (NS_SUCCEEDED(aRv)) {
rv = mImageCapture->PostBlobEvent(blob);
} else {
rv =
mImageCapture->PostErrorEvent(dom::ImageCaptureError::PHOTO_ERROR, aRv);
}
// Ensure ImageCapture dereference on main thread here because the TakePhoto()
// sequences stopped here.
mImageCapture = nullptr;
return rv;
}
void CaptureTask::AttachTrack() {
MOZ_ASSERT(NS_IsMainThread());
dom::MediaStreamTrack* track = mImageCapture->GetVideoStreamTrack();
track->AddPrincipalChangeObserver(this);
track->AddListener(mEventListener.get());
track->AddDirectListener(this);
}
void CaptureTask::DetachTrack() {
MOZ_ASSERT(NS_IsMainThread());
dom::MediaStreamTrack* track = mImageCapture->GetVideoStreamTrack();
track->RemovePrincipalChangeObserver(this);
track->RemoveListener(mEventListener.get());
track->RemoveDirectListener(this);
}
void CaptureTask::PrincipalChanged(dom::MediaStreamTrack* aMediaStreamTrack) {
MOZ_ASSERT(NS_IsMainThread());
mPrincipalChanged = true;
}
void CaptureTask::NotifyRealtimeTrackData(MediaTrackGraph* aGraph,
TrackTime aTrackOffset,
const MediaSegment& aMedia) {
MOZ_ASSERT(aMedia.GetType() == MediaSegment::VIDEO);
const VideoSegment& video = static_cast<const VideoSegment&>(aMedia);
// Callback for encoding complete, it calls on main thread.
class EncodeComplete : public dom::EncodeCompleteCallback {
public:
explicit EncodeComplete(CaptureTask* aTask) : mTask(aTask) {}
bool CanBeDeletedOnAnyThread() override {
// EncodeComplete is used from the main thread only.
return false;
}
nsresult ReceiveBlobImpl(
already_AddRefed<dom::BlobImpl> aBlobImpl) override {
MOZ_ASSERT(NS_IsMainThread());
RefPtr<dom::BlobImpl> blobImpl(aBlobImpl);
mTask->TaskComplete(blobImpl.forget(), NS_OK);
mTask = nullptr;
return NS_OK;
}
protected:
RefPtr<CaptureTask> mTask;
};
for (VideoSegment::ConstChunkIterator iter(video); !iter.IsEnded();
iter.Next()) {
VideoChunk chunk = *iter;
// Extract the first valid video frame.
VideoFrame frame;
if (chunk.IsNull()) {
continue;
}
RefPtr<layers::Image> image;
if (chunk.mFrame.GetForceBlack()) {
// Create a black image.
image = VideoFrame::CreateBlackImage(chunk.mFrame.GetIntrinsicSize());
} else {
image = chunk.mFrame.GetImage();
}
if (!image) {
MOZ_ASSERT(image);
continue;
}
bool wasGrabbed = mImageGrabbedOrTrackEnd.exchange(true);
if (wasGrabbed) {
return;
}
// Encode image.
nsresult rv;
nsAutoString type(u"image/jpeg"_ns);
nsAutoString options;
rv = dom::ImageEncoder::ExtractDataFromLayersImageAsync(
type, options, false, image, false, new EncodeComplete(this));
if (NS_FAILED(rv)) {
PostTrackEndEvent();
}
}
}
void CaptureTask::PostTrackEndEvent() {
bool wasGrabbed = mImageGrabbedOrTrackEnd.exchange(true);
if (wasGrabbed) {
return;
}
// Got track end or finish event, stop the task.
class TrackEndRunnable : public Runnable {
public:
explicit TrackEndRunnable(CaptureTask* aTask)
: mozilla::Runnable("TrackEndRunnable"), mTask(aTask) {}
NS_IMETHOD Run() override {
mTask->TaskComplete(nullptr, NS_ERROR_FAILURE);
mTask = nullptr;
return NS_OK;
}
protected:
RefPtr<CaptureTask> mTask;
};
IC_LOG("Got MediaTrack track removed or finished event.");
nsCOMPtr<nsIRunnable> event = new TrackEndRunnable(this);
SchedulerGroup::Dispatch(event.forget());
}
} // namespace mozilla