Avisynth does not support TSCC codec ?

[dyanglp]

I am using Camtasia Studio 2 to prepare some training material and try to get subtitle work...(long story in short), the avi generated by Camtasia uses TSCC codec and I do have it installed in the system, so I created an Avisynth script as below:

AviSourc("training.avi",false,FourCC="TSCC")

and drag the avs file onto VirtualdubMod, it gave:

"Avisynth open failure:
AVISourc: couldn't locate a decompressor for fourcc TSCC..."

So I changed "TSCC" into "tscc"

This time it didn't complain, but when I looked up the "file information",it gave:
FourCC code: FourCC: [] Unknown
Decompressor: Uncompressed RGB32

So it seems that the Avisynth didn't load the codec requested and the movie is totally useless when playback.

When I drag the avi file directly to the virtualdub, the file information shows:

FourCC doce: FourCC: [tscc]
Decompressor: TechSmith Screen Capture Codec

I am using Avisynth 255, Windows XP SP2

Any help is appreciated.

[celtic_druid]

Why not just use avisource("training.avi",false) if VDub can use the correct fourCC automatically, then AVISynth should to.