media/video/capture/fake_video_capture_device.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 // Implementation of a fake VideoCaptureDevice class. Used for testing other
   6 // video capture classes when no real hardware is available.
   7
   8 #ifndef MEDIA_VIDEO_CAPTURE_FAKE_VIDEO_CAPTURE_DEVICE_H_
   9 #define MEDIA_VIDEO_CAPTURE_FAKE_VIDEO_CAPTURE_DEVICE_H_
  10
  11 #include <string>
  12
  13 #include "base/memory/scoped_ptr.h"
  14 #include "base/threading/thread.h"
  15 #include "media/video/capture/video_capture_device.h"
  16
  17 namespace media {
  18
  19 class MEDIA_EXPORT FakeVideoCaptureDevice : public VideoCaptureDevice {
  20  public:
  21   static VideoCaptureDevice* Create(const Name& device_name);
  22   virtual ~FakeVideoCaptureDevice();
  23   // Used for testing. This will make sure the next call to Create will
  24   // return NULL;
  25   static void SetFailNextCreate();
  26
  27   static void GetDeviceNames(Names* device_names);
  28
  29   // VideoCaptureDevice implementation.
  30   virtual void Allocate(const VideoCaptureCapability& capture_format,
  31                          VideoCaptureDevice::EventHandler* observer) OVERRIDE;
  32   virtual void Start() OVERRIDE;
  33   virtual void Stop() OVERRIDE;
  34   virtual void DeAllocate() OVERRIDE;
  35   virtual const Name& device_name() OVERRIDE;
  36
  37  private:
  38   // Flag indicating the internal state.
  39   enum InternalState {
  40     kIdle,
  41     kAllocated,
  42     kCapturing,
  43     kError
  44   };
  45   explicit FakeVideoCaptureDevice(const Name& device_name);
  46
  47   // Called on the capture_thread_.
  48   void OnCaptureTask();
  49
  50   // EXPERIMENTAL, similar to allocate, but changes resolution and calls
  51   // observer->OnFrameInfoChanged(VideoCaptureCapability&)
  52   void Reallocate();
  53   void PopulateCapabilitiesRoster();
  54
  55   Name device_name_;
  56   VideoCaptureDevice::EventHandler* observer_;
  57   InternalState state_;
  58   base::Thread capture_thread_;
  59   scoped_ptr<uint8[]> fake_frame_;
  60   int frame_count_;
  61   VideoCaptureCapability capture_format_;
  62
  63   // When the device is configured as mutating video captures, this vector
  64   // holds the available ones which are used in sequence, restarting at the end.
  65   std::vector<VideoCaptureCapability> capabilities_roster_;
  66   int capabilities_roster_index_;
  67
  68   static bool fail_next_create_;
  69
  70   DISALLOW_IMPLICIT_CONSTRUCTORS(FakeVideoCaptureDevice);
  71 };
  72
  73 }  // namespace media
  74
  75 #endif  // MEDIA_VIDEO_CAPTURE_FAKE_VIDEO_CAPTURE_DEVICE_H_