如何使用ConfigureFilterUsingProfile DirectShow未压缩的记录调整质量？

Question

I am digging into DirectShow to record video from USB device and from the following code:

hr= m_captureGraphBuilder.SetOutputFileName(MediaSubType.Asf, 
  "E:\\exa.wmv", out pMux, out fSinkFilter);
//
//configure which video setting is used by graph
//                
IConfigAsfWriter2 lConfig = pMux as IConfigAsfWriter2;
Guid asfFilter = new Guid("8C45B4C7-4AEB-4f78-A5EC-88420B9DADEF");
lConfig.ConfigureFilterUsingProfileGuid(asfFilter);
m_captureGraphBuilder.RenderStream(null,null, m_deviceFilter, null, pMux);
m_mediaCtrl = m_graphBuilder as IMediaControl;
m_mediaCtrl.Run();

I am able to record video but it is lowest quality, i am new to directshow and things,

How can I increase quality?

Answer 1

The GUID's well-known name is: WMProfile_V80_288VideoOnly , which is:

Windows Media Video 8 for Dial-up Modem (No audio, 28.8 Kbps) -- Use this profile when creating video-only content for target audiences with dial-up modems.

Note that this way to set up encoding is somewhat outdated though still okay:

The profiles listed below all use the version 8 Windows Media Audio and Windows Media Video codecs. There are no predefined system profiles that use the Windows Media 9 Series codecs.

You can alternatively set up encoding profile as MSDN suggests above, or pick a better suitable identifier from the mentioned. The values are available in Windows SDK, or. for instance, here .

See related questions:

• DirectShow.NET sample - load a better profile
• Video Capture output always in 320x240 despite changing resolution (features ConfigureFilterUsingProfile as opposed to your ConfigureFilterUsingProfileGuid )