How to combine multiple Video streams in single stream in C#?

[shashank]

Here is my sample code---in C#

IGraphBuilder oFilterGraph = (IGraphBuilder)new
FilterGraph();
VideoMixingRenderer9 oVideoMixingRenderer = new
VideoMixingRenderer9();
oFilterGraph.AddFilter((IBaseFilter)oVideoMixingRenderer,
"Video");

IVMRFilterConfig9 oVMRFilterConfig =
(IVMRFilterConfig9)oVideoMixingRenderer;
oVMRFilterConfig.SetRenderingMode(VMR9Mode.Windowed);
oVMRFilterConfig.SetNumberOfStreams(2);

oVMRFilterConfig.SetRenderingPrefs(VMR9RenderPrefs.None);

IVMRMixerControl9 oIVMRMixerControl =
(IVMRMixerControl9)oVideoMixingRenderer;

NormalizedRect oNormalizedRect = new NormalizedRect();
oNormalizedRect.left = 0.0F;
oNormalizedRect.top = 0.0F;
oNormalizedRect.bottom = 0.5F;
oNormalizedRect.right = 0.5F;

NormalizedRect oNormalizedRect1 = new NormalizedRect();
oNormalizedRect.left = 0.5F;
oNormalizedRect.top = 0.5F;
oNormalizedRect.bottom = 1;
oNormalizedRect.right = 1;

int iStreamId1 = oFilterGraph.RenderFile("c:\\file1.wmv",
string.Empty);
int iStreamId2 = oFilterGraph.RenderFile("c:\\file2.wmv",
string.Empty);

oIVMRMixerControl.SetOutputRect(0, ref oNormalizedRect);
oIVMRMixerControl.SetOutputRect(1, ref
oNormalizedRect1);

oIVMRMixerControl.SetAlpha(0, 1);
oIVMRMixerControl.SetAlpha(1, 1);

IMediaControl oMediaControl = (IMediaControl)oFilterGraph;
oMediaControl.Run();

I tried with the code but could not succeed. It is showing only one
video in control & not showing other one.