标签:init filter array 插入 uid property cat exce end
DirectShow .Net 实现视频
1 1、获取视频采集设备IBaseFilter接口对象的方法 2 3 //获取所有视频设备名称 4 public ArrayList GetVideoInputDevice() 5 { return GetDeviceCollection(FilterCategory.VideoInputDevice);} 6 private ArrayList GetDeviceCollection(Guid DeviceType) 7 { 8 ArrayList returnString = new ArrayList(); 9 foreach (DsDevice ds in DsDevice.GetDevicesOfCat(DeviceType)) 10 { 11 returnString.Add(ds.Name); 12 } 13 return returnString; 14 } 15 16 //通过获取到的视频设备名称设置采集设备的IBaseFilter对象 17 public bool SetVideoInputDevice(string VideoInputDeviceName) 18 { //创建视频输入设备接口 19 theVideoDevice = CreateFilter(FilterCategory.VideoInputDevice, VideoInputDeviceName); 20 } 21 //通过过滤器类型和过滤器名称获取IBaseFilter接口 22 private IBaseFilter CreateFilter(Guid category, string friendlyname) 23 { 24 object source = null; 25 Guid iid = typeof(IBaseFilter).GUID; 26 foreach (DsDevice device in DsDevice.GetDevicesOfCat(category)) 27 { 28 if (device.Name.CompareTo(friendlyname) == 0) 29 { 30 device.Mon.BindToObject(null, null, ref iid, out source); 31 break; 32 } 33 } 34 35 return (IBaseFilter)source; 36 } 37 38 2、初始化基本的接口对象 39 40 private void InitInterfaces() 41 { 42 int hr = 0; 43 44 // 获取IGraphBuilder接口对象 45 this.m_graphBuilder = (IGraphBuilder)new FilterGraph(); 46 //获取ICaptureGraphBuilder2接口对象 47 this.m_captureGraphBuilder = (ICaptureGraphBuilder2)new CaptureGraphBuilder2(); 48 //获取m_graphBuilder 接口对象的IMediaControl对象 49 this.m_mediaControl = (IMediaControl)this.m_graphBuilder; 50 //获取m_graphBuilder 接口对象的IVideoWindow对象 51 this.m_videoWindow = (IVideoWindow)this.m_graphBuilder; 52 //获取m_graphBuilder 接口对象的IMediaEventEx对象 53 this.m_mediaEventEx = (IMediaEventEx)this.m_graphBuilder; 54 //设置ICaptureGraphBuilder2的IGraphBuilder接口对象为当前对象 55 hr = this.m_captureGraphBuilder.SetFiltergraph(this.m_graphBuilder); 56 DsError.ThrowExceptionForHR(hr); 57 //注册事件到应用程序的窗体上 58 hr = this.m_mediaEventEx.SetNotifyWindow(this.hwnPropertyPageOwner, WM_GRAPHNOTIFY, IntPtr.Zero); 59 DsError.ThrowExceptionForHR(hr); 60 } 61 62 63 64 65 66 67 68 3、开始视频预览 69 public void VideoPreview() 70 try 71 { 72 73 int hr = 0; 74 hr = this.m_graphBuilder.AddFilter(theVideoDevice, "Video Capture"); 75 DsError.ThrowExceptionForHR(hr); 76 77 // 通过theVideoDevice(IBaseFilter)视频接口对象的Preview Pin预览 78 hr = this.m_captureGraphBuilder.RenderStream(PinCategory.Preview, MediaType.Video, theVideoDevice, null, null); 79 DsError.ThrowExceptionForHR(hr); 80 81 //插入SampleGrabber 82 m_pinStill = DsFindPin.ByCategory(theVideoDevice, PinCategory.Still, 0); 83 84 if (m_pinStill == null) 85 { 86 m_pinStill = DsFindPin.ByCategory(theVideoDevice, PinCategory.Capture, 0); 87 } 88 89 90 // 获取theVideoDevice的IAMVideoControl对象,对于具有Still Pin的对象可以获到,采集设备不具备Still Pin,那么该对象将为Null 91 m_VidControl = theVideoDevice as IAMVideoControl; 92 93 // 设置采集视频参数 94 if (this.videoHeight + this.videoWidth + this.videoStride > 0) 95 { 96 SetConfigParms(m_pinStill, this.videoWidth, this.videoHeight, 24); 97 } 98 99 //开始拍照功能所需的接口对象 100 // 获得SampleGrabber对象接口 101 sampGrabber = new SampleGrabber() as ISampleGrabber; 102 103 // 配置sample grabber 104 baseGrabFlt = sampGrabber as IBaseFilter; 105 ConfigureSampleGrabber(sampGrabber); 106 107 // 将sample grabber添加到图形过滤器中 108 hr = m_graphBuilder.AddFilter(baseGrabFlt, "Ds.NET Grabber"); 109 DsError.ThrowExceptionForHR(hr); 110 111 //通过渲染将采集设备的相关输出Pin与sample grabber对象的输入Pin连接起来 112 //如果采集设备提供Still Pin,则通过Still Pin连接,否则直接使用Capture Pin连接 113 if (m_VidControl!=null) 114 { 115 hr = this.m_captureGraphBuilder.RenderStream(PinCategory.Still, MediaType.Video, theVideoDevice, null, baseGrabFlt); 116 DsError.ThrowExceptionForHR(hr); 117 118 } 119 else 120 { 121 hr = this.m_captureGraphBuilder.RenderStream(PinCategory.Capture, MediaType.Video, theVideoDevice, null, baseGrabFlt); 122 DsError.ThrowExceptionForHR(hr); 123 } 124 //设置抓取图片相关参数 125 SaveSizeInfo(sampGrabber); 126 //拍照功能所需的接口对象添加结束 127 128 129 // 开始将视频窗口绑定到主窗体上 130 hr = this.m_videoWindow.put_Owner(this.hwnVideoWindowOwner); 131 DsError.ThrowExceptionForHR(hr); 132 133 hr = this.m_videoWindow.put_WindowStyle(WindowStyle.Child | WindowStyle.ClipChildren); 134 DsError.ThrowExceptionForHR(hr); 135 136 if (this.m_videoWindow != null) 137 { 138 this.m_videoWindow.SetWindowPosition(0, 0, this.videoWidth, this.videoHeight); 139 } 140 141 142 hr = this.m_videoWindow.put_Visible(OABool.True); 143 DsError.ThrowExceptionForHR(hr); 144 145 // 开始预览采集设备采集到的视频 146 hr = this.m_mediaControl.Run(); 147 148 DsError.ThrowExceptionForHR(hr); 149 m_IsPreview = true; 150 } 151 catch 152 { 153 m_IsPreview = false; 154 throw new Exception("VideoPreview函数出现异常,视频预览失败!"); 155 156 } 157 }
标签:init filter array 插入 uid property cat exce end
原文地址:http://www.cnblogs.com/endv/p/6082784.html