We've announced a while ago that the BitmapEffects pipeline within WinFx (particularly in Windows Presentation Foundation) would be extensible. However, no samples were provided. Today I'm posting the first sample that we've created for test purposes. It demonstrates how to build a simple BitmapEffect.
RGB Adjustor BitmapEffect (February CTP): RGBFilterEffect_code.zip (code no longer available)
RGB Adjustor BitmapEffect (February CTP): RGBFilterEffect_compiled.zip (code no longer available)