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.
5 // TODO(hclam): This class should be renamed to VideoCaptureService.
7 // This class provides access to a video capture device in the browser
8 // process through IPC. The main function is to deliver video frames
13 // VideoCaptureImplManager lives only on the render thread. All methods
14 // must be called on this thread.
16 // VideoFrames are delivered on the IO thread. Callbacks provided by
17 // a client are also called on the IO thread.
19 #ifndef CONTENT_RENDERER_MEDIA_VIDEO_CAPTURE_IMPL_MANAGER_H_
20 #define CONTENT_RENDERER_MEDIA_VIDEO_CAPTURE_IMPL_MANAGER_H_
24 #include "base/callback.h"
25 #include "base/memory/linked_ptr.h"
26 #include "base/memory/ref_counted.h"
27 #include "base/memory/scoped_ptr.h"
28 #include "base/memory/weak_ptr.h"
29 #include "base/message_loop/message_loop_proxy.h"
30 #include "base/synchronization/lock.h"
31 #include "base/threading/thread_checker.h"
32 #include "content/common/content_export.h"
33 #include "content/common/media/video_capture.h"
34 #include "media/video/capture/video_capture_types.h"
38 class VideoCaptureImpl;
39 class VideoCaptureMessageFilter;
41 class CONTENT_EXPORT VideoCaptureImplManager {
43 VideoCaptureImplManager();
44 virtual ~VideoCaptureImplManager();
46 // Open a device associated with the session ID.
47 // This method must be called before any methods with the same ID
49 // Returns a callback that should be used to release the acquired
51 base::Closure UseDevice(media::VideoCaptureSessionId id);
53 // Start receiving video frames for the given session ID.
55 // |state_update_cb| will be called on the IO thread when capturing
57 // States will be one of the following four:
58 // * VIDEO_CAPTURE_STATE_STARTED
59 // * VIDEO_CAPTURE_STATE_STOPPED
60 // * VIDEO_CAPTURE_STATE_PAUSED
61 // * VIDEO_CAPTURE_STATE_ERROR
63 // |deliver_frame_cb| will be called on the IO thread when a video
66 // Returns a callback that is used to stop capturing. Note that stopping
67 // video capture is not synchronous. Client should handle the case where
68 // callbacks are called after capturing is instructed to stop, typically
69 // by binding the passed callbacks on a WeakPtr.
70 base::Closure StartCapture(
71 media::VideoCaptureSessionId id,
72 const media::VideoCaptureParams& params,
73 const VideoCaptureStateUpdateCB& state_update_cb,
74 const VideoCaptureDeliverFrameCB& deliver_frame_cb);
76 // Get supported formats supported by the device for the given session
77 // ID. |callback| will be called on the IO thread.
78 void GetDeviceSupportedFormats(
79 media::VideoCaptureSessionId id,
80 const VideoCaptureDeviceFormatsCB& callback);
82 // Get supported formats currently in use for the given session ID.
83 // |callback| will be called on the IO thread.
84 void GetDeviceFormatsInUse(
85 media::VideoCaptureSessionId id,
86 const VideoCaptureDeviceFormatsCB& callback);
88 // Make all existing VideoCaptureImpl instances stop/resume delivering
89 // video frames to their clients, depends on flag |suspend|.
90 void SuspendDevices(bool suspend);
92 VideoCaptureMessageFilter* video_capture_message_filter() const {
97 virtual VideoCaptureImpl* CreateVideoCaptureImplForTesting(
98 media::VideoCaptureSessionId id,
99 VideoCaptureMessageFilter* filter) const;
102 void StopCapture(int client_id, media::VideoCaptureSessionId id);
103 void UnrefDevice(media::VideoCaptureSessionId id);
105 // The int is used to count clients of the corresponding VideoCaptureImpl.
106 // VideoCaptureImpl objects are owned by this object. But they are
107 // destroyed on the IO thread. These are raw pointers because we destroy
109 typedef std::map<media::VideoCaptureSessionId,
110 std::pair<int, VideoCaptureImpl*> >
111 VideoCaptureDeviceMap;
112 VideoCaptureDeviceMap devices_;
114 // This is an internal ID for identifying clients of VideoCaptureImpl.
115 // The ID is global for the render process.
118 scoped_refptr<VideoCaptureMessageFilter> filter_;
120 // Bound to the render thread.
121 base::ThreadChecker thread_checker_;
123 // Bound to the render thread.
124 // NOTE: Weak pointers must be invalidated before all other member variables.
125 base::WeakPtrFactory<VideoCaptureImplManager> weak_factory_;
127 DISALLOW_COPY_AND_ASSIGN(VideoCaptureImplManager);
130 } // namespace content
132 #endif // CONTENT_RENDERER_MEDIA_VIDEO_CAPTURE_IMPL_MANAGER_H_