content/renderer/media/webrtc/webrtc_video_capturer_adapter.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_RENDERER_MEDIA_WEBRTC_WEBRTC_VIDEO_CAPTURER_ADAPTER_H_
   6 #define CONTENT_RENDERER_MEDIA_WEBRTC_WEBRTC_VIDEO_CAPTURER_ADAPTER_H_
   7
   8 #include <vector>
   9
  10 #include "base/compiler_specific.h"
  11 #include "base/threading/thread_checker.h"
  12 #include "content/common/content_export.h"
  13 #include "media/base/video_capture_types.h"
  14 #include "media/base/video_frame.h"
  15 #include "third_party/libjingle/source/talk/media/base/videocapturer.h"
  16
  17 namespace content {
  18
  19 // WebRtcVideoCapturerAdapter implements a simple cricket::VideoCapturer that is
  20 // used for VideoCapturing in libJingle and especially in PeerConnections.
  21 // The class is created and destroyed on the main render thread.
  22 // PeerConnection access cricket::VideoCapturer from a libJingle worker thread.
  23 // An instance of WebRtcVideoCapturerAdapter is owned by an instance of
  24 // webrtc::VideoSourceInterface in libJingle. The implementation of
  25 // webrtc::VideoSourceInterface guarantees that this object is not deleted
  26 // while it is still used in libJingle.
  27 class CONTENT_EXPORT WebRtcVideoCapturerAdapter
  28     : NON_EXPORTED_BASE(public cricket::VideoCapturer) {
  29  public:
  30   explicit WebRtcVideoCapturerAdapter(bool is_screencast);
  31   ~WebRtcVideoCapturerAdapter() override;
  32
  33   // OnFrameCaptured delivers video frames to libjingle. It must be called on
  34   // libjingles worker thread.
  35   // This method is virtual for testing purposes.
  36   virtual void OnFrameCaptured(const scoped_refptr<media::VideoFrame>& frame);
  37
  38  private:
  39   // cricket::VideoCapturer implementation.
  40   // These methods are accessed from a libJingle worker thread.
  41   cricket::CaptureState Start(
  42       const cricket::VideoFormat& capture_format) override;
  43   void Stop() override;
  44   bool IsRunning() override;
  45   bool GetPreferredFourccs(std::vector<uint32>* fourccs) override;
  46   bool GetBestCaptureFormat(const cricket::VideoFormat& desired,
  47                             cricket::VideoFormat* best_format) override;
  48   bool IsScreencast() const override;
  49
  50   // |thread_checker_| is bound to the libjingle worker thread.
  51   base::ThreadChecker thread_checker_;
  52
  53   const bool is_screencast_;
  54   bool running_;
  55   base::TimeDelta first_frame_timestamp_;
  56
  57   class MediaVideoFrameFactory;
  58
  59   DISALLOW_COPY_AND_ASSIGN(WebRtcVideoCapturerAdapter);
  60 };
  61
  62 }  // namespace content
  63
  64 #endif  // CONTENT_RENDERER_MEDIA_WEBRTC_WEBRTC_VIDEO_CAPTURER_ADAPTER_H_