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/video/capture/video_capture_device.h"
23#include "media/video/capture/video_capture_types.h"
24#include "media/video/capture/win/capability_list_win.h"
25#include "media/video/capture/win/sink_filter_win.h"
26#include "media/video/capture/win/sink_input_pin_win.h"
27
28namespace media {
29
30// All the methods in the class can only be run on a COM initialized thread.
31class VideoCaptureDeviceWin
32    : public base::NonThreadSafe,
33      public VideoCaptureDevice,
34      public SinkFilterObserver {
35 public:
36  // A utility class that wraps the AM_MEDIA_TYPE type and guarantees that
37  // we free the structure when exiting the scope.  DCHECKing is also done to
38  // avoid memory leaks.
39  class ScopedMediaType {
40   public:
41    ScopedMediaType() : media_type_(NULL) {}
42    ~ScopedMediaType() { Free(); }
43
44    AM_MEDIA_TYPE* operator->() { return media_type_; }
45    AM_MEDIA_TYPE* get() { return media_type_; }
46    void Free();
47    AM_MEDIA_TYPE** Receive();
48
49   private:
50    void FreeMediaType(AM_MEDIA_TYPE* mt);
51    void DeleteMediaType(AM_MEDIA_TYPE* mt);
52
53    AM_MEDIA_TYPE* media_type_;
54  };
55
56  static HRESULT GetDeviceFilter(const std::string& device_id,
57                                 const CLSID device_class_id,
58                                 IBaseFilter** filter);
59  static base::win::ScopedComPtr<IPin> GetPin(IBaseFilter* filter,
60                                              PIN_DIRECTION pin_dir,
61                                              REFGUID category,
62                                              REFGUID major_type);
63  static VideoPixelFormat TranslateMediaSubtypeToPixelFormat(
64      const GUID& sub_type);
65
66  explicit VideoCaptureDeviceWin(const Name& device_name);
67  virtual ~VideoCaptureDeviceWin();
68  // Opens the device driver for this device.
69  bool Init();
70
71  // VideoCaptureDevice implementation.
72  virtual void AllocateAndStart(
73      const VideoCaptureParams& params,
74      scoped_ptr<VideoCaptureDevice::Client> client) OVERRIDE;
75  virtual void StopAndDeAllocate() OVERRIDE;
76
77 private:
78  enum InternalState {
79    kIdle,  // The device driver is opened but camera is not in use.
80    kCapturing,  // Video is being captured.
81    kError  // Error accessing HW functions.
82            // User needs to recover by destroying the object.
83  };
84
85  // Implements SinkFilterObserver.
86  virtual void FrameReceived(const uint8* buffer, int length);
87
88  bool CreateCapabilityMap();
89  void SetAntiFlickerInCaptureFilter();
90  HRESULT InstantiateWDMFiltersAndPins();
91  HRESULT AddWDMCrossbarFilterToGraphAndConnect();
92  void SetErrorState(const std::string& reason);
93
94  Name device_name_;
95  InternalState state_;
96  scoped_ptr<VideoCaptureDevice::Client> client_;
97
98  base::win::ScopedComPtr<IBaseFilter> capture_filter_;
99  base::win::ScopedComPtr<IGraphBuilder> graph_builder_;
100  base::win::ScopedComPtr<IMediaControl> media_control_;
101  base::win::ScopedComPtr<IPin> input_sink_pin_;
102  base::win::ScopedComPtr<IPin> output_capture_pin_;
103  // Used when using a MJPEG decoder.
104  base::win::ScopedComPtr<IBaseFilter> mjpg_filter_;
105  base::win::ScopedComPtr<IPin> input_mjpg_pin_;
106  base::win::ScopedComPtr<IPin> output_mjpg_pin_;
107  // Used for WDM devices as specified by |device_name_|. These devices need a
108  // WDM Crossbar Filter upstream from the Capture filter.
109  base::win::ScopedComPtr<IBaseFilter> crossbar_filter_;
110  base::win::ScopedComPtr<IPin> crossbar_video_output_pin_;
111  base::win::ScopedComPtr<IPin> analog_video_input_pin_;
112
113  scoped_refptr<SinkFilter> sink_filter_;
114
115  // Map of all capabilities this device support.
116  CapabilityList capabilities_;
117  VideoCaptureFormat capture_format_;
118
119  DISALLOW_IMPLICIT_CONSTRUCTORS(VideoCaptureDeviceWin);
120};
121
122}  // namespace media
123
124#endif  // MEDIA_VIDEO_CAPTURE_WIN_VIDEO_CAPTURE_DEVICE_WIN_H_
125