Is there a decent AviSynth version of the VDub Chroma smoother?

[Z.Sath]

Hi Guys.

Encoding some NTSC Laserdic cartoons to Mpeg2, and am trying to tone down the peculiar blockyness you get with Reds (is it called cross-chrominance?)

Anyway, tried Cnr2 in AviSynth: cnr2() and Cnr("xxx", 4, 5, 255)

Neither seem to mute the effect like the VDub Chroma Smoother.

Any suggestions?

Thanks in advance

Paul.