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序号：63574 发表者：hhui 发表日期：2003-12-04 16:48:38
<br>主题：视频捕获和传送
<br>内容：从摄像头抓取视频，然后发送,里面的几个filter怎么生成,怎么连接?哪位高人能否指点一二（有源代码的更好） 
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<font color=red>答案被接受</font><br>回复者：莉莉 回复日期：2003-12-04 17:42:25
<br>内容：Capture啊，1: Create the filter graph manager and query for interfaces.<BR>&nbsp;&nbsp;&nbsp;&nbsp;hr = CoCreateInstance(CLSID_CaptureGraphBuilder2, NULL, CLSCTX_INPROC_SERVER,<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;IID_ICaptureGraphBuilder2, (void **)&amp;pCaptureGraph);<BR><BR><BR>2:Use a method of the capture graph builder .To create an output path for the stream<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; hr = pCaptureGraph-&gt;SetOutputFileName(&amp;MEDIASUBTYPE_Asf, <BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;L&#34;C:\\MyWebcam111111.asf&#34;, &amp;pASFWriter, &amp;pSink);<BR><BR>3:Now get the filter graph manager<BR><BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; hr = pCaptureGraph-&gt;GetFiltergraph(&amp;pGraph);<BR><BR>4:Using QueryInterface on the graph builder<BR><BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; hr = pGraph-&gt;QueryInterface(IID_IMediaControl, (void **)&amp;pControl);<BR><BR>5:create the video input filter from the webcam,获得capture的设备（摄像头），得到指标，然后使用IFilterGraph::AddFilter把获得的指针加进the graph。<BR>&nbsp;&nbsp;&nbsp;&nbsp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; hr = GetVideoInputFilter(&amp;pVideoInputFilter, L&#34;Logitech&#34;);<BR>&nbsp;&nbsp;&nbsp;&nbsp;if (SUCCEEDED(hr)) {<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;hr = pGraph-&gt;AddFilter(pVideoInputFilter, L&#34;Webcam Video Capture&#34;);<BR>&nbsp;&nbsp;&nbsp;&nbsp;}<BR>&nbsp;&nbsp;&nbsp;&nbsp;GetVideoInputFilter为自定义的函数，使用System Device Enumerator查找Capture Filter.见 Microsoft DirectX 9.0 中的Selecting a Capture Device。<BR><BR>6：然后使用RenderStream分别把preview和capture 的pin Render出来，........<BR><BR>7:再接着就可以run 这个graph拉，接下来就是等待结束。<BR><BR>&nbsp;&nbsp;&nbsp;&nbsp;if (SUCCEEDED(hr))<BR>&nbsp;&nbsp;&nbsp;&nbsp;{<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;// Run the graph.<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;hr = pControl-&gt;Run();<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if (SUCCEEDED(hr))<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{ <BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;....<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}<BR><BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;// And let's stop the filter graph<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;hr = pControl-&gt;Stop();<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;......<BR>&nbsp;&nbsp;&nbsp;&nbsp; }
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回复者：bird 回复日期：2003-12-05 08:53:17
<br>内容：How to Write a Capture Application!<BR><BR><BR>DirectShow sdk 里有!
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