Legacy ImageMagick Discussions Archive

I have some rather large maps which have some fine details which are difficult to locate while looking at the entire map. What I would do in gimp is to select by color, expand selection by 1000px, feather, fill, shrink by 200px, feather, delete.
I have, however, over 80 maps and due to their large size they're real memory hogs.
Any help would be appreciated.

You could turn all other colours black and turn the required colour white (possibly with fuzz).

Then dilate and erode with morphology.

Feather with blur.

I don't understand your other operations, but they are probably easy in IM. From the greyscale version I outline above, you could highlight the map, like using a highlighter pen. Or do something else.

Gimp is 8-bit. IM is usually 16-bit, so uses twice as much memory. You could use Q8 IM.