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 media {
  65 class VideoCaptureCapability;
  66 }
  67
  68 namespace content {
  69 class MediaStreamManager;
  70
  71 class CONTENT_EXPORT VideoCaptureHost
  72     : public BrowserMessageFilter,
  73       public VideoCaptureControllerEventHandler {
  74  public:
  75   explicit VideoCaptureHost(MediaStreamManager* media_stream_manager);
  76
  77   // BrowserMessageFilter implementation.
  78   virtual void OnChannelClosing() OVERRIDE;
  79   virtual void OnDestruct() const OVERRIDE;
  80   virtual bool OnMessageReceived(const IPC::Message& message,
  81                                  bool* message_was_ok) OVERRIDE;
  82
  83   // VideoCaptureControllerEventHandler implementation.
  84   virtual void OnError(const VideoCaptureControllerID& id) OVERRIDE;
  85   virtual void OnBufferCreated(const VideoCaptureControllerID& id,
  86                                base::SharedMemoryHandle handle,
  87                                int length,
  88                                int buffer_id) OVERRIDE;
  89   virtual void OnBufferDestroyed(const VideoCaptureControllerID& id,
  90                                  int buffer_id) OVERRIDE;
  91   virtual void OnBufferReady(
  92       const VideoCaptureControllerID& id,
  93       int buffer_id,
  94       base::Time timestamp,
  95       const media::VideoCaptureFormat& format) OVERRIDE;
  96   virtual void OnEnded(const VideoCaptureControllerID& id) OVERRIDE;
  97
  98  private:
  99   friend class BrowserThread;
 100   friend class base::DeleteHelper<VideoCaptureHost>;
 101   friend class MockVideoCaptureHost;
 102   friend class VideoCaptureHostTest;
 103
 104   virtual ~VideoCaptureHost();
 105
 106   // IPC message: Start capture on the VideoCaptureDevice referenced by
 107   // |session_id|. |device_id| is an id created by VideoCaptureMessageFilter
 108   // to identify a session between a VideoCaptureMessageFilter and a
 109   // VideoCaptureHost.
 110   void OnStartCapture(int device_id,
 111                       media::VideoCaptureSessionId session_id,
 112                       const media::VideoCaptureParams& params);
 113   void OnControllerAdded(
 114       int device_id,
 115       const base::WeakPtr<VideoCaptureController>& controller);
 116   void DoControllerAddedOnIOThread(
 117       int device_id,
 118       const base::WeakPtr<VideoCaptureController>& controller);
 119
 120   // IPC message: Stop capture on device referenced by |device_id|.
 121   void OnStopCapture(int device_id);
 122
 123   // IPC message: Pause capture on device referenced by |device_id|.
 124   void OnPauseCapture(int device_id);
 125
 126   // IPC message: Receive an empty buffer from renderer. Send it to device
 127   // referenced by |device_id|.
 128   void OnReceiveEmptyBuffer(int device_id, int buffer_id);
 129
 130   // Send a newly created buffer to the VideoCaptureMessageFilter.
 131   void DoSendNewBufferOnIOThread(
 132       const VideoCaptureControllerID& controller_id,
 133       base::SharedMemoryHandle handle,
 134       int length,
 135       int buffer_id);
 136
 137   void DoSendFreeBufferOnIOThread(
 138       const VideoCaptureControllerID& controller_id,
 139       int buffer_id);
 140
 141   // Send a filled buffer to the VideoCaptureMessageFilter.
 142   void DoSendFilledBufferOnIOThread(
 143       const VideoCaptureControllerID& controller_id,
 144       int buffer_id,
 145       base::Time timestamp,
 146       const media::VideoCaptureFormat& format);
 147
 148   // Handle error coming from VideoCaptureDevice.
 149   void DoHandleErrorOnIOThread(const VideoCaptureControllerID& controller_id);
 150
 151   void DoEndedOnIOThread(const VideoCaptureControllerID& controller_id);
 152
 153   void DeleteVideoCaptureControllerOnIOThread(
 154       const VideoCaptureControllerID& controller_id);
 155
 156   MediaStreamManager* media_stream_manager_;
 157
 158   typedef std::map<VideoCaptureControllerID,
 159                    base::WeakPtr<VideoCaptureController> > EntryMap;
 160
 161   // A map of VideoCaptureControllerID to the VideoCaptureController to which it
 162   // is connected. An entry in this map holds a null controller while it is in
 163   // the process of starting.
 164   EntryMap entries_;
 165
 166   DISALLOW_COPY_AND_ASSIGN(VideoCaptureHost);
 167 };
 168
 169 }  // namespace content
 170
 171 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_VIDEO_CAPTURE_HOST_H_