virtualdub displaying frazz from 368x480 file

[BabaG]

i have a file that gspot says is 368x480. i'm trying to load it into avisynth
to do a little processing but, on loading the script, vdub just show a lot
of diagonal frazz. what do i need to add to this simple script?

fwiw, it's a vob file because i found that, on another, similar file, i got
an error loading it into vdub but changing the file suffix to vob allowed
vdub to open it.

LoadPlugin("C:\Program Files\AviSynth 2.5\plugins\TIVTC.dll")
LoadPlugin("C:\Program Files\AviSynth 2.5\plugins\MPEGDecoder.dll")
MPEGSource("E:\receiving\Accordin1952.vob")

TFM(order=1) #0=bff, 1=tff
TDecimate()

thanks for any help,
BabaG