summaryrefslogtreecommitdiffstats
path: root/dom/media/imagecapture/CaptureTask.h
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--dom/media/imagecapture/CaptureTask.h90
1 files changed, 90 insertions, 0 deletions
diff --git a/dom/media/imagecapture/CaptureTask.h b/dom/media/imagecapture/CaptureTask.h
new file mode 100644
index 0000000000..efcd0e84b2
--- /dev/null
+++ b/dom/media/imagecapture/CaptureTask.h
@@ -0,0 +1,90 @@
+/* -*- 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 CAPTURETASK_H
+#define CAPTURETASK_H
+
+#include "MediaTrackGraph.h"
+#include "MediaTrackListener.h"
+#include "PrincipalChangeObserver.h"
+
+namespace mozilla {
+
+namespace dom {
+class BlobImpl;
+class ImageCapture;
+class MediaStreamTrack;
+} // namespace dom
+
+/**
+ * CaptureTask retrieves image from MediaTrack and encodes the image to jpeg in
+ * ImageEncoder. The whole procedures start at AttachTrack(), it will add this
+ * class into MediaTrack and retrieves an image in MediaTrackGraph thread.
+ * Once the image is retrieved, it will be sent to ImageEncoder and the encoded
+ * blob will be sent out via encoder callback in main thread.
+ *
+ * CaptureTask holds a reference of ImageCapture to ensure ImageCapture won't be
+ * released during the period of the capturing process described above.
+ */
+class CaptureTask : public DirectMediaTrackListener,
+ public dom::PrincipalChangeObserver<dom::MediaStreamTrack> {
+ public:
+ class MediaTrackEventListener;
+
+ // DirectMediaTrackListener methods
+ void NotifyRealtimeTrackData(MediaTrackGraph* aGraph, TrackTime aTrackOffset,
+ const MediaSegment& aMedia) override;
+
+ // PrincipalChangeObserver<MediaStreamTrack> methods
+ void PrincipalChanged(dom::MediaStreamTrack* aMediaStreamTrack) override;
+
+ // CaptureTask methods.
+
+ // It is called when aBlob is ready to post back to script in company with
+ // aRv == NS_OK. If aRv is not NS_OK, it will post an error event to script.
+ //
+ // Note:
+ // this function should be called on main thread.
+ nsresult TaskComplete(already_AddRefed<dom::BlobImpl> aBlobImpl,
+ nsresult aRv);
+
+ // Add listeners into MediaStreamTrack and PrincipalChangeObserver.
+ // It should be on main thread only.
+ void AttachTrack();
+
+ // Remove listeners from MediaStreamTrack and PrincipalChangeObserver.
+ // It should be on main thread only.
+ void DetachTrack();
+
+ // CaptureTask should be created on main thread.
+ explicit CaptureTask(dom::ImageCapture* aImageCapture);
+
+ protected:
+ virtual ~CaptureTask() = default;
+
+ // Post a runnable on main thread to end this task and call TaskComplete to
+ // post error event to script. It is called off-main-thread.
+ void PostTrackEndEvent();
+
+ // The ImageCapture associates with this task. This reference count should not
+ // change in this class unless it clears this reference after a blob or error
+ // event to script.
+ RefPtr<dom::ImageCapture> mImageCapture;
+
+ RefPtr<MediaTrackEventListener> mEventListener;
+
+ // True when an image is retrieved from the video track, or MediaTrackGraph
+ // sends a track finish, end, or removed event. Any thread.
+ Atomic<bool> mImageGrabbedOrTrackEnd;
+
+ // True after MediaStreamTrack principal changes while waiting for a photo
+ // to finish and we should raise a security error.
+ bool mPrincipalChanged;
+};
+
+} // namespace mozilla
+
+#endif // CAPTURETASK_H