使用Directshow和C＃錄制視頻時的文本疊加

Question

通過使用DirectShowLib，我可以使用ASF writter錄制視頻，這里是開始錄制的代碼

 try
        {
            IBaseFilter capFilter = null;
            IBaseFilter asfWriter = null;
            IFileSinkFilter pTmpSink = null;
            ICaptureGraphBuilder2 captureGraph = null;               
            GetVideoDevice();
            if (availableVideoInputDevices.Count > 0)
            {
                //
                //init capture graph
                //
                graphBuilder = (IFilterGraph2)new FilterGraph();
                captureGraph = (ICaptureGraphBuilder2)new CaptureGraphBuilder2();
                //
                //sets filter object from graph
                //
                captureGraph.SetFiltergraph(graphBuilder);
                //
                //which device will use graph setting
                //
                graphBuilder.AddSourceFilterForMoniker(AvailableVideoInputDevices.First().Mon, null, AvailableVideoInputDevices.First().Name, out capFilter);
                captureDeviceName = AvailableVideoInputDevices.First().Name;                    
                //
                //check saving path is exsist or not;if not then create
                //
                if (!Directory.Exists(ConstantHelper.RootDirectoryName + "\\Assets\\Video\\"))
                {
                    Directory.CreateDirectory(ConstantHelper.RootDirectoryName + "\\Assets\\Video\\");
                }
                #region WMV                   
                //
                //sets output file name,and file type
                //
                captureGraph.SetOutputFileName(MediaSubType.Asf, ConstantHelper.RootDirectoryName + "\\Assets\\Video\\" + videoFilename + ".wmv", out asfWriter, out pTmpSink);                    
                //
                //configure which video setting is used by graph
                //                
                IConfigAsfWriter lConfig = asfWriter as IConfigAsfWriter;
                Guid asfFilter = new Guid("8C45B4C7-4AEB-4f78-A5EC-88420B9DADEF");
                lConfig.ConfigureFilterUsingProfileGuid(asfFilter);
                #endregion
                //
                //render the stram to output file using graph setting
                //
                captureGraph.RenderStream(null, null, capFilter, null, asfWriter);
                m_mediaCtrl = graphBuilder as IMediaControl;
                m_mediaCtrl.Run();
                isVideoRecordingStarted = true;
                VideoStarted(m_mediaCtrl, null);

現在，我想在對視頻進行重新編碼時在視頻上添加文字疊加層，並且可以使用DirectshowLib嗎？

例如，當開始錄制視頻時，應該使用文本覆蓋來錄制視頻。

Answer 1

我在軟件中通過將SampleGrabber過濾器插入到圖形中的方式進行此SampleGrabber ，並在圖片到達時將其轉換為Bitmap對象，然后使用Graphics對其進行繪制。

Answer 2

查看DirectShow.Net示例中的DMO和DxLogo示例，以完成所需的工作。 您可以在DxSnap示例中找到DanielMošmondor解釋的內容...

http://directshownet.sourceforge.net/