how to use a binary mask as a "stencil" for a grayscale image?

Hey everyone,

I have a binary mask (first attached image) that I want to use to trace-out the image of a gray-scale picture (second attacked image) and create another image in that manner.

I tried the simple AND operation, but the newly created image is a binary, not grayscale. I want to use the mask to crop out the image, without changing anything else.

Thanks in advance for any tips!

Answer 1

[Image Analyst]

Simply use the inverse of the mask to set those pixels to zero.

imageCopy = grayImage; % Make a copy so you don't destroy the original.
imageCopy(~mask) = 0;  % Set black areas to black, leaving gray areas intact.

[Naim]

simple, obvious, and worked just how I wanted it to!