media/capture/video/video_capture_device_factory.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 MEDIA_VIDEO_CAPTURE_VIDEO_CAPTURE_DEVICE_FACTORY_H_
   6 #define MEDIA_VIDEO_CAPTURE_VIDEO_CAPTURE_DEVICE_FACTORY_H_
   7
   8 #include "base/threading/thread_checker.h"
   9 #include "media/capture/video/video_capture_device.h"
  10
  11 namespace media {
  12
  13 // VideoCaptureDeviceFactory is the base class for creation of video capture
  14 // devices in the different platforms. VCDFs are created by MediaStreamManager
  15 // on IO thread and plugged into VideoCaptureManager, who owns and operates them
  16 // in Device Thread (a.k.a. Audio Thread).
  17 class MEDIA_EXPORT VideoCaptureDeviceFactory {
  18  public:
  19   static scoped_ptr<VideoCaptureDeviceFactory> CreateFactory(
  20       scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner);
  21
  22   VideoCaptureDeviceFactory();
  23   virtual ~VideoCaptureDeviceFactory();
  24
  25   // Creates a VideoCaptureDevice object. Returns NULL if something goes wrong.
  26   virtual scoped_ptr<VideoCaptureDevice> Create(
  27       const VideoCaptureDevice::Name& device_name) = 0;
  28
  29   // Asynchronous version of GetDeviceNames calling back to |callback|.
  30   virtual void EnumerateDeviceNames(const base::Callback<
  31       void(scoped_ptr<media::VideoCaptureDevice::Names>)>& callback);
  32
  33   // Gets the supported formats of a particular device attached to the system.
  34   // This method should be called before allocating or starting a device. In
  35   // case format enumeration is not supported, or there was a problem, the
  36   // formats array will be empty.
  37   virtual void GetDeviceSupportedFormats(
  38       const VideoCaptureDevice::Name& device,
  39       VideoCaptureFormats* supported_formats) = 0;
  40
  41  protected:
  42   // Gets the names of all video capture devices connected to this computer.
  43   // Used by the default implementation of EnumerateDeviceNames().
  44   virtual void GetDeviceNames(VideoCaptureDevice::Names* device_names) = 0;
  45
  46   base::ThreadChecker thread_checker_;
  47
  48  private:
  49   static VideoCaptureDeviceFactory* CreateVideoCaptureDeviceFactory(
  50       scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner);
  51
  52   DISALLOW_COPY_AND_ASSIGN(VideoCaptureDeviceFactory);
  53 };
  54
  55 }  // namespace media
  56
  57 #endif  // MEDIA_VIDEO_CAPTURE_VIDEO_CAPTURE_DEVICE_FACTORY_H_