Screen Capture of RMVB, how do I

[Flame10]

I'm using Real Alternative codec to play rmvb video files, but I'm unable to take any screenshots from media player classic [gabest's], neither using specialised tool like snagit.

Anybody know how to do it, without converting the whole file to another format. I just need screenshots

Ty

[Flame10]

Ok solved it

Used Directshowsource in AviSynth and am able to take screenshots now

[Sirber]

Set MPC to "Render WMR9" for RV then use "Save screenshot" in File menu.