[Coco] Vol. IX No. 1 Scanned

[John R. Hogerhuis]

Seems like you should be able to use gimp to make the b&w mask.

Barring that, you could try imagemagick to reduce the color depth. It's
got all kinds of dials to turn, and buttons to press, just need to find
the right ones, and you could do all your scans as a batch.

-- John.