Using imageData and maskData

[Ken Norris]

Howdy,

I'm getting headache trying to get my mind wrapped around these things.
There must be a better explanation and examples somewhere. I really need to
see heavily commented scripts in a working stack, or a genuine tutorial.
I've looked at Easy Transparency, but I don't know what's going on. The
dictionary description of imageData function is over my head. I'm not
getting it.

What I want to do is make an imported 8bit image into a mask for an image
for a windowShape. It's black, but I have to make the white areas
transparent.

About 4 months ago, I did it with another image, but I can't remember how. I
remember creating a repeat loop that did it because I remember watching it
work its way through the image. I probably put a few suggestions together
and just stumbled into it. I still have the image, but that doesn't help
now.

Someone is going to have to lead me by the hand one baby step at a time. Any
takers?

Ken N.