1 files changed, 197 insertions, 0 deletions
diff --git a/dom/media/imagecapture/CaptureTask.cpp b/dom/media/imagecapture/CaptureTask.cpp
new file mode 100644
index 000000000..589ba5a42
--- /dev/null
+++ b/dom/media/imagecapture/CaptureTask.cpp
@@ -0,0 +1,197 @@
+/* -*- 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/. */
+
+#include "CaptureTask.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 "gfxUtils.h"
+#include "nsThreadUtils.h"
+
+namespace mozilla {
+
+class CaptureTask::MediaStreamEventListener : public MediaStreamTrackListener
+{
+public:
+  explicit MediaStreamEventListener(CaptureTask* aCaptureTask)
+    : mCaptureTask(aCaptureTask) {};
+
+  // MediaStreamListener methods.
+  void NotifyEnded() override
+  {
+    if(!mCaptureTask->mImageGrabbedOrTrackEnd) {
+      mCaptureTask->PostTrackEndEvent();
+    }
+  }
+
+private:
+  CaptureTask* mCaptureTask;
+};
+
+CaptureTask::CaptureTask(dom::ImageCapture* aImageCapture)
+  : mImageCapture(aImageCapture)
+  , mEventListener(new MediaStreamEventListener(this))
+  , mImageGrabbedOrTrackEnd(false)
+  , mPrincipalChanged(false)
+{
+}
+
+nsresult
+CaptureTask::TaskComplete(already_AddRefed<dom::Blob> aBlob, nsresult aRv)
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  DetachTrack();
+
+  nsresult rv;
+  RefPtr<dom::Blob> blob(aBlob);
+
+  // We have to set the parent because the blob has been generated with a valid one.
+  if (blob) {
+    blob = dom::Blob::Create(mImageCapture->GetParentObject(), blob->Impl());
+  }
+
+  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::VideoStreamTrack* track = mImageCapture->GetVideoStreamTrack();
+  track->AddPrincipalChangeObserver(this);
+  track->AddListener(mEventListener.get());
+  track->AddDirectListener(this);
+}
+
+void
+CaptureTask::DetachTrack()
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  dom::VideoStreamTrack* 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::SetCurrentFrames(const VideoSegment& aSegment)
+{
+  if (mImageGrabbedOrTrackEnd) {
+    return;
+  }
+
+  // Callback for encoding complete, it calls on main thread.
+  class EncodeComplete : public dom::EncodeCompleteCallback
+  {
+  public:
+    explicit EncodeComplete(CaptureTask* aTask) : mTask(aTask) {}
+
+    nsresult ReceiveBlob(already_AddRefed<dom::Blob> aBlob) override
+    {
+      RefPtr<dom::Blob> blob(aBlob);
+      mTask->TaskComplete(blob.forget(), NS_OK);
+      mTask = nullptr;
+      return NS_OK;
+    }
+
+  protected:
+    RefPtr<CaptureTask> mTask;
+  };
+
+  VideoSegment::ConstChunkIterator iter(aSegment);
+
+
+
+  while (!iter.IsEnded()) {
+    VideoChunk chunk = *iter;
+
+    // Extract the first valid video frame.
+    VideoFrame frame;
+    if (!chunk.IsNull()) {
+      RefPtr<layers::Image> image;
+      if (chunk.mFrame.GetForceBlack()) {
+        // Create a black image.
+        image = VideoFrame::CreateBlackImage(chunk.mFrame.GetIntrinsicSize());
+      } else {
+        image = chunk.mFrame.GetImage();
+      }
+      MOZ_ASSERT(image);
+      mImageGrabbedOrTrackEnd = true;
+
+      // Encode image.
+      nsresult rv;
+      nsAutoString type(NS_LITERAL_STRING("image/jpeg"));
+      nsAutoString options;
+      rv = dom::ImageEncoder::ExtractDataFromLayersImageAsync(
+                                type,
+                                options,
+                                false,
+                                image,
+                                new EncodeComplete(this));
+      if (NS_FAILED(rv)) {
+        PostTrackEndEvent();
+      }
+      return;
+    }
+    iter.Next();
+  }
+}
+
+void
+CaptureTask::PostTrackEndEvent()
+{
+  mImageGrabbedOrTrackEnd = true;
+
+  // Got track end or finish event, stop the task.
+  class TrackEndRunnable : public Runnable
+  {
+  public:
+    explicit TrackEndRunnable(CaptureTask* aTask)
+      : mTask(aTask) {}
+
+    NS_IMETHOD Run() override
+    {
+      mTask->TaskComplete(nullptr, NS_ERROR_FAILURE);
+      mTask = nullptr;
+      return NS_OK;
+    }
+
+  protected:
+    RefPtr<CaptureTask> mTask;
+  };
+
+  IC_LOG("Got MediaStream track removed or finished event.");
+  NS_DispatchToMainThread(new TrackEndRunnable(this));
+}
+
+} // namespace mozilla