media/capture/video/win/video_capture_device_win.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 // Windows specific implementation of VideoCaptureDevice.
   6 // DirectShow is used for capturing. DirectShow provide its own threads
   7 // for capturing.
   8
   9 #ifndef MEDIA_VIDEO_CAPTURE_WIN_VIDEO_CAPTURE_DEVICE_WIN_H_
  10 #define MEDIA_VIDEO_CAPTURE_WIN_VIDEO_CAPTURE_DEVICE_WIN_H_
  11
  12 // Avoid including strsafe.h via dshow as it will cause build warnings.
  13 #define NO_DSHOW_STRSAFE
  14 #include <dshow.h>
  15
  16 #include <map>
  17 #include <string>
  18
  19 #include "base/threading/non_thread_safe.h"
  20 #include "base/threading/thread.h"
  21 #include "base/win/scoped_comptr.h"
  22 #include "media/base/video_capture_types.h"
  23 #include "media/capture/video/video_capture_device.h"
  24 #include "media/capture/video/win/capability_list_win.h"
  25 #include "media/capture/video/win/sink_filter_win.h"
  26 #include "media/capture/video/win/sink_input_pin_win.h"
  27
  28 namespace media {
  29
  30 // All the methods in the class can only be run on a COM initialized thread.
  31 class VideoCaptureDeviceWin : public base::NonThreadSafe,
  32                               public VideoCaptureDevice,
  33                               public SinkFilterObserver {
  34  public:
  35   // A utility class that wraps the AM_MEDIA_TYPE type and guarantees that
  36   // we free the structure when exiting the scope.  DCHECKing is also done to
  37   // avoid memory leaks.
  38   class ScopedMediaType {
  39    public:
  40     ScopedMediaType() : media_type_(NULL) {}
  41     ~ScopedMediaType() { Free(); }
  42
  43     AM_MEDIA_TYPE* operator->() { return media_type_; }
  44     AM_MEDIA_TYPE* get() { return media_type_; }
  45     void Free();
  46     AM_MEDIA_TYPE** Receive();
  47
  48    private:
  49     void FreeMediaType(AM_MEDIA_TYPE* mt);
  50     void DeleteMediaType(AM_MEDIA_TYPE* mt);
  51
  52     AM_MEDIA_TYPE* media_type_;
  53   };
  54
  55   static HRESULT GetDeviceFilter(const std::string& device_id,
  56                                  const CLSID device_class_id,
  57                                  IBaseFilter** filter);
  58   static base::win::ScopedComPtr<IPin> GetPin(IBaseFilter* filter,
  59                                               PIN_DIRECTION pin_dir,
  60                                               REFGUID category,
  61                                               REFGUID major_type);
  62   static VideoCapturePixelFormat TranslateMediaSubtypeToPixelFormat(
  63       const GUID& sub_type);
  64
  65   explicit VideoCaptureDeviceWin(const Name& device_name);
  66   ~VideoCaptureDeviceWin() override;
  67   // Opens the device driver for this device.
  68   bool Init();
  69
  70   // VideoCaptureDevice implementation.
  71   void AllocateAndStart(const VideoCaptureParams& params,
  72                         scoped_ptr<VideoCaptureDevice::Client> client) override;
  73   void StopAndDeAllocate() override;
  74
  75  private:
  76   enum InternalState {
  77     kIdle,       // The device driver is opened but camera is not in use.
  78     kCapturing,  // Video is being captured.
  79     kError       // Error accessing HW functions.
  80                  // User needs to recover by destroying the object.
  81   };
  82
  83   // Implements SinkFilterObserver.
  84   void FrameReceived(const uint8* buffer, int length) override;
  85
  86   bool CreateCapabilityMap();
  87   void SetAntiFlickerInCaptureFilter();
  88   void SetErrorState(const std::string& reason);
  89
  90   Name device_name_;
  91   InternalState state_;
  92   scoped_ptr<VideoCaptureDevice::Client> client_;
  93
  94   base::win::ScopedComPtr<IBaseFilter> capture_filter_;
  95
  96   base::win::ScopedComPtr<IGraphBuilder> graph_builder_;
  97   base::win::ScopedComPtr<ICaptureGraphBuilder2> capture_graph_builder_;
  98
  99   base::win::ScopedComPtr<IMediaControl> media_control_;
 100   base::win::ScopedComPtr<IPin> input_sink_pin_;
 101   base::win::ScopedComPtr<IPin> output_capture_pin_;
 102
 103   scoped_refptr<SinkFilter> sink_filter_;
 104
 105   // Map of all capabilities this device support.
 106   CapabilityList capabilities_;
 107   VideoCaptureFormat capture_format_;
 108
 109   DISALLOW_IMPLICIT_CONSTRUCTORS(VideoCaptureDeviceWin);
 110 };
 111
 112 }  // namespace media
 113
 114 #endif  // MEDIA_VIDEO_CAPTURE_WIN_VIDEO_CAPTURE_DEVICE_WIN_H_