I'm trying to make a 3d-box like effect (don't know how it's called correctly), similar to what raise is doing, so image would look like this:

So what I tried to do:
Having this base image:

I made
Code: Select all
convert bath.jpg -gravity southwest -splice 25x25 -raise 25 -chop 25x25 framed.jpg

So, as you can see, it's almost what I need excepting bottom right corner, which should be cropped up-right or smth. How I can do it? Crop works only on rectangular basis. Or maybe there's an easier way to do whole effect?
Thank you.