Make cricket::VideoCapturer implement VideoSourceInterface

webrtc/media/base/videobroadcaster.h

+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef WEBRTC_MEDIA_BASE_VIDEOBROADCASTER_H_
+#define WEBRTC_MEDIA_BASE_VIDEOBROADCASTER_H_
+
+#include <utility>
+#include <vector>
+
+#include "webrtc/base/thread_checker.h"
+#include "webrtc/media/base/videoframe.h"
+#include "webrtc/media/base/videosinkinterface.h"
+#include "webrtc/media/base/videosourceinterface.h"
+
+namespace rtc {
+
+class VideoBroadCaster : public VideoSourceInterface<cricket::VideoFrame>,
+                         public VideoSinkInterface<cricket::VideoFrame> {

[pthatcher1, 2016/02/08 20:59:39]

"broadcast" is one word, so "Broadcaster", with a lowercase "c".

[perkj_webrtc, 2016/02/09 13:23:57]

sorry - I realized that on my way home yesterday...... 

+ public:
+  VideoBroadCaster();
+  void AddSink(VideoSinkInterface<cricket::VideoFrame>* sink) override;
+  void RemoveSink(VideoSinkInterface<cricket::VideoFrame>* sink) override;
+  void AddOrUpdateSink(VideoSinkInterface<cricket::VideoFrame>* sink,
+                       const VideoSinkHints& hints) override;
+
+  // Returns true if the next frame will be delivered to at least one sink.
+  bool FrameWillBeDelivered() const;

[pthatcher1, 2016/02/08 20:59:39]

How about calling this frame_wanted()?

[perkj_webrtc, 2016/02/09 13:23:57]

Done.

+
+  // Returns the hints a source is requested to fulfill. They are aggregated
+  // by all hints from all sinks.
+  VideoSinkHints DerivedHints() const;

[pthatcher1, 2016/02/08 20:59:39]

I'd prefer a name like AggregateSinkHints(), or better yet just sink_hints()

[perkj_webrtc, 2016/02/09 13:23:57]

Done.

+
+  void OnFrame(const cricket::VideoFrame& frame) override;
+
+ protected:
+  ThreadChecker thread_checker_;
+  std::pair<VideoSinkInterface<cricket::VideoFrame>*, VideoSinkHints>
+      current_hints_;

[nisse-webrtc, 2016/02/08 14:57:04]

This makes me puzzled. Maybe simply don't understand stl, but I had expected
something like

std::vector<std::pair<VideoSinkInterface<cricket::VideoFrame>*, hints>> sinks_;

[pthatcher1, 2016/02/08 20:59:39]

I was thinking the same thing.

[perkj_webrtc, 2016/02/09 13:23:57]

I wanted to not actually do the aggregation of wants in this cl and just check
that they are all the same. But it is easy to implement for rotation now that we
always require an explicit VideoWant from all sinks.

+  using Sinks = std::vector<VideoSinkInterface<cricket::VideoFrame>*>;
+  Sinks sinks_;
+};
+
+}  // namespace rtc
+
+#endif  // WEBRTC_MEDIA_BASE_VIDEOBROADCASTER_H_