content/browser/renderer_host/media/video_capture_host.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 // VideoCaptureHost serves video capture related messages from
   6 // VideoCaptureMessageFilter which lives inside the render process.
   7 //
   8 // This class is owned by RenderProcessHostImpl, and instantiated on UI
   9 // thread, but all other operations and method calls happen on IO thread.
  10 //
  11 // Here's an example of a typical IPC dialog for video capture:
  12 //
  13 //   Renderer                             VideoCaptureHost
  14 //      |                                        |
  15 //      |  VideoCaptureHostMsg_Start >           |
  16 //      | < VideoCaptureMsg_StateChanged         |
  17 //      |        (VIDEO_CAPTURE_STATE_STARTED)   |
  18 //      | < VideoCaptureMsg_NewBuffer(1)         |
  19 //      | < VideoCaptureMsg_NewBuffer(2)         |
  20 //      | < VideoCaptureMsg_NewBuffer(3)         |
  21 //      |                                        |
  22 //      | < VideoCaptureMsg_BufferReady(1)       |
  23 //      | < VideoCaptureMsg_BufferReady(2)       |
  24 //      | VideoCaptureHostMsg_BufferReady(1) >   |
  25 //      | < VideoCaptureMsg_BufferReady(3)       |
  26 //      | VideoCaptureHostMsg_BufferReady(2) >   |
  27 //      | < VideoCaptureMsg_BufferReady(1)       |
  28 //      | VideoCaptureHostMsg_BufferReady(3) >   |
  29 //      | < VideoCaptureMsg_BufferReady(2)       |
  30 //      | VideoCaptureHostMsg_BufferReady(1) >   |
  31 //      |             ...                        |
  32 //      | < VideoCaptureMsg_BufferReady(3)       |
  33 //      |                                        |
  34 //      |             ... (resolution change)    |
  35 //      | < VideoCaptureMsg_FreeBuffer(1)        |  Buffers are re-allocated
  36 //      | < VideoCaptureMsg_NewBuffer(4)         |  at a larger size, as
  37 //      | < VideoCaptureMsg_BufferReady(4)       |  needed.
  38 //      | VideoCaptureHostMsg_BufferReady(2) >   |
  39 //      | < VideoCaptureMsg_FreeBuffer(2)        |
  40 //      | < VideoCaptureMsg_NewBuffer(5)         |
  41 //      | < VideoCaptureMsg_BufferReady(5)       |
  42 //      |             ...                        |
  43 //      |                                        |
  44 //      | < VideoCaptureMsg_BufferReady          |
  45 //      | VideoCaptureHostMsg_Stop >             |
  46 //      | VideoCaptureHostMsg_BufferReady >      |
  47 //      | < VideoCaptureMsg_StateChanged         |
  48 //      |         (VIDEO_CAPTURE_STATE_STOPPED)  |
  49 //      v                                        v
  50
  51 #ifndef CONTENT_BROWSER_RENDERER_HOST_MEDIA_VIDEO_CAPTURE_HOST_H_
  52 #define CONTENT_BROWSER_RENDERER_HOST_MEDIA_VIDEO_CAPTURE_HOST_H_
  53
  54 #include <map>
  55
  56 #include "base/memory/ref_counted.h"
  57 #include "base/memory/weak_ptr.h"
  58 #include "base/sequenced_task_runner_helpers.h"
  59 #include "content/browser/renderer_host/media/video_capture_controller.h"
  60 #include "content/common/content_export.h"
  61 #include "content/public/browser/browser_message_filter.h"
  62 #include "ipc/ipc_message.h"
  63
  64 namespace content {
  65 class MediaStreamManager;
  66
  67 class CONTENT_EXPORT VideoCaptureHost
  68     : public BrowserMessageFilter,
  69       public VideoCaptureControllerEventHandler {
  70  public:
  71   explicit VideoCaptureHost(MediaStreamManager* media_stream_manager);
  72
  73   // BrowserMessageFilter implementation.
  74   virtual void OnChannelClosing() OVERRIDE;
  75   virtual void OnDestruct() const OVERRIDE;
  76   virtual bool OnMessageReceived(const IPC::Message& message,
  77                                  bool* message_was_ok) OVERRIDE;
  78
  79   // VideoCaptureControllerEventHandler implementation.
  80   virtual void OnError(const VideoCaptureControllerID& id) OVERRIDE;
  81   virtual void OnBufferCreated(const VideoCaptureControllerID& id,
  82                                base::SharedMemoryHandle handle,
  83                                int length,
  84                                int buffer_id) OVERRIDE;
  85   virtual void OnBufferDestroyed(const VideoCaptureControllerID& id,
  86                                  int buffer_id) OVERRIDE;
  87   virtual void OnBufferReady(const VideoCaptureControllerID& id,
  88                              int buffer_id,
  89                              base::TimeTicks timestamp,
  90                              const media::VideoCaptureFormat& format) OVERRIDE;
  91   virtual void OnEnded(const VideoCaptureControllerID& id) OVERRIDE;
  92
  93  private:
  94   friend class BrowserThread;
  95   friend class base::DeleteHelper<VideoCaptureHost>;
  96   friend class MockVideoCaptureHost;
  97   friend class VideoCaptureHostTest;
  98
  99   virtual ~VideoCaptureHost();
 100
 101   // IPC message: Start capture on the VideoCaptureDevice referenced by
 102   // |session_id|. |device_id| is an id created by VideoCaptureMessageFilter
 103   // to identify a session between a VideoCaptureMessageFilter and a
 104   // VideoCaptureHost.
 105   void OnStartCapture(int device_id,
 106                       media::VideoCaptureSessionId session_id,
 107                       const media::VideoCaptureParams& params);
 108   void OnControllerAdded(
 109       int device_id,
 110       const base::WeakPtr<VideoCaptureController>& controller);
 111   void DoControllerAddedOnIOThread(
 112       int device_id,
 113       const base::WeakPtr<VideoCaptureController>& controller);
 114
 115   // IPC message: Stop capture on device referenced by |device_id|.
 116   void OnStopCapture(int device_id);
 117
 118   // IPC message: Pause capture on device referenced by |device_id|.
 119   void OnPauseCapture(int device_id);
 120
 121   // IPC message: Receive an empty buffer from renderer. Send it to device
 122   // referenced by |device_id|.
 123   void OnReceiveEmptyBuffer(int device_id, int buffer_id);
 124
 125   // Send a newly created buffer to the VideoCaptureMessageFilter.
 126   void DoSendNewBufferOnIOThread(
 127       const VideoCaptureControllerID& controller_id,
 128       base::SharedMemoryHandle handle,
 129       int length,
 130       int buffer_id);
 131
 132   void DoSendFreeBufferOnIOThread(
 133       const VideoCaptureControllerID& controller_id,
 134       int buffer_id);
 135
 136   // Send a filled buffer to the VideoCaptureMessageFilter.
 137   void DoSendFilledBufferOnIOThread(
 138       const VideoCaptureControllerID& controller_id,
 139       int buffer_id,
 140       base::TimeTicks timestamp,
 141       const media::VideoCaptureFormat& format);
 142
 143   // Handle error coming from VideoCaptureDevice.
 144   void DoHandleErrorOnIOThread(const VideoCaptureControllerID& controller_id);
 145
 146   void DoEndedOnIOThread(const VideoCaptureControllerID& controller_id);
 147
 148   void DeleteVideoCaptureControllerOnIOThread(
 149       const VideoCaptureControllerID& controller_id);
 150
 151   MediaStreamManager* media_stream_manager_;
 152
 153   typedef std::map<VideoCaptureControllerID,
 154                    base::WeakPtr<VideoCaptureController> > EntryMap;
 155
 156   // A map of VideoCaptureControllerID to the VideoCaptureController to which it
 157   // is connected. An entry in this map holds a null controller while it is in
 158   // the process of starting.
 159   EntryMap entries_;
 160
 161   DISALLOW_COPY_AND_ASSIGN(VideoCaptureHost);
 162 };
 163
 164 }  // namespace content
 165
 166 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_VIDEO_CAPTURE_HOST_H_