src/content/renderer/media/video_capture_impl_manager.h

   1 // Copyright (c) 2012 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 // VideoCaptureImplManager manages video capture devices in renderer process.
   6 // The video capture clients use AddDevice() to get a pointer to
   7 // video capture device. VideoCaputreImplManager supports multiple clients
   8 // accessing same device.
   9
  10 #ifndef CONTENT_RENDERER_MEDIA_VIDEO_CAPTURE_IMPL_MANAGER_H_
  11 #define CONTENT_RENDERER_MEDIA_VIDEO_CAPTURE_IMPL_MANAGER_H_
  12
  13 #include <list>
  14 #include <map>
  15
  16 #include "base/message_loop/message_loop_proxy.h"
  17 #include "base/threading/thread.h"
  18 #include "base/synchronization/lock.h"
  19 #include "content/common/content_export.h"
  20 #include "media/video/capture/video_capture.h"
  21
  22 namespace content {
  23
  24 class VideoCaptureImpl;
  25 class VideoCaptureMessageFilter;
  26
  27 class CONTENT_EXPORT VideoCaptureImplManager
  28     : public base::RefCountedThreadSafe<VideoCaptureImplManager> {
  29  public:
  30   VideoCaptureImplManager();
  31
  32   // Called by video capture client |handler| to add device referenced
  33   // by |id| to VideoCaptureImplManager's list of opened device list.
  34   // A pointer to VideoCapture is returned to client so that client can
  35   // operate on that pointer, such as StartCaptrue, StopCapture.
  36   virtual media::VideoCapture* AddDevice(
  37       media::VideoCaptureSessionId id,
  38       media::VideoCapture::EventHandler* handler);
  39
  40   // Called by video capture client |handler| to remove device referenced
  41   // by |id| from VideoCaptureImplManager's list of opened device list.
  42   virtual void RemoveDevice(media::VideoCaptureSessionId id,
  43                             media::VideoCapture::EventHandler* handler);
  44
  45   // Make all existing VideoCaptureImpl instances stop/resume delivering
  46   // video frames to their clients, depends on flag |suspend|.
  47   virtual void SuspendDevices(bool suspend);
  48
  49   VideoCaptureMessageFilter* video_capture_message_filter() const {
  50     return filter_.get();
  51   }
  52
  53  protected:
  54   virtual ~VideoCaptureImplManager();
  55
  56  private:
  57   friend class base::RefCountedThreadSafe<VideoCaptureImplManager>;
  58
  59   struct Device {
  60     Device(VideoCaptureImpl* device,
  61            media::VideoCapture::EventHandler* handler);
  62     ~Device();
  63
  64     VideoCaptureImpl* vc;
  65     std::list<media::VideoCapture::EventHandler*> clients;
  66   };
  67
  68   void FreeDevice(VideoCaptureImpl* vc);
  69
  70   typedef std::map<media::VideoCaptureSessionId, Device*> Devices;
  71   Devices devices_;
  72   base::Lock lock_;
  73   scoped_refptr<VideoCaptureMessageFilter> filter_;
  74   base::Thread thread_;
  75   scoped_refptr<base::MessageLoopProxy> message_loop_proxy_;
  76
  77   DISALLOW_COPY_AND_ASSIGN(VideoCaptureImplManager);
  78 };
  79
  80 }  // namespace content
  81
  82 #endif  // CONTENT_RENDERER_MEDIA_VIDEO_CAPTURE_IMPL_MANAGER_H_