ICaptureGraphBuilder2::RenderStream的连接如何断开?

[SonicX]

我用
fBuild.RenderStream(@PIN_CATEGORY_PREVIEW, @MEDIATYPE_Audio, fCap, nil, pDSoundRender)
连接后如果不需要的该如何断开?

Delphi7
////////////////////////////////////////////////////////
fCap:=GetBaseFilter(0); //得到视频设备过程略
CocreateInstance(CLSID_CaptureGraphBuilder2, nil, CLSCTX_INPROC, IID_ICaptureGraphBuilder2, pBuild);
CocreateInstance(CLSID_FilterGraph, nil, CLSCTX_INPROC, IID_IFilterGraph, pGraph);
pBuild.SetFiltergraph(pGraph);
fGraph.AddFilter(fCap, 'VideoCap'); //添加视频设备Filter
CoCreateInstance(CLSID_DSoundRender, nil, CLSCTX_INPROC_SERVER, IID_IBaseFilter, pSoundRender);
fGraph.AddFilter(pSoundRender, 'SoundRender'); //添加声音Filter
fBuild.RenderStream(@PIN_CATEGORY_PREVIEW, @MEDIATYPE_Audio, fCap, nil, pDSoundRender); //建立声音播放连接
fBuild.RenderStream(@PIN_CATEGORY_PREVIEW, @MEDIATYPE_Video, fCap, nil, nil); //建立视频播放连接
fGraph.QueryInterface(IID_IMediaControl, fMControl);
fMControl.Run; //播放

[asddg67]

	HRESULT hr = S_OK;
	if (m_pMC)
	{
		OAFilterState state;
		int times = 10;
		while(times)
		{
			m_pMC->GetState(40, &state);
			if (State_Stopped == state)
			{
				if (m_pSourceFilter)
					NukeDownStream(m_pGB, m_pSourceFilter);

				RemoveAllFilterInGraph(m_pGB);
				return true;
			}
			hr = m_pMC->Stop();
			times--;
		}
	}
	if (FAILED(hr))
	{
		return false;
	}

[瓶盒]

一般而言是找到连接的两个Pin,然后对两个Pin分别调用IGraphBuilder::Disconnect( IPin *ppin)去断开