I've got an AVI from an old B/W video, which has some vertical lines or scratches. (Eg, the dark band through the man's eye.)

The bands are about 9-10 pixels wide, and are throughout most of the video, moving slightly from frame to frame.

I want to clean it up in Avisynth.

I tried to use Fizick's descratch, like this:

descratch(mindif=2, minlen=200, maxgap=20)

But it wasn't very successful. It detected and filtered the scratch about 20% of the time, leaving a flickering effect even worse than the original.

In the docs, it says:
maxwidth - maximal scratch width (1 or 3, default=3)

Does this mean it only detects scratches up to 3 pixels wide? As mentioned, those in this video are 9-10 pixels wide.

Any suggestions on tweaking descratch's parameters, or other filters to try?