Add Random Phase inside eclipse-masked image.

[June Kang]

I've tried to add random noise only to phase of the image based on this code.

http://visionscience.com/pipermail/visionlist/2007/002181.html

However, Now I want to this job WITHIN the image which eclipse-shaped masked.
like this.

http://24.media.tumblr.com/5cd8bb5bbd95dbb3d9d4a66a979df9e6/tumblr_mn9jmhY0Le1sswo2do2_500.png

Of course I have a mask itself and easily import it to matlab and transfer to 'logic matrix'

http://24.media.tumblr.com/e803af2129dff40cd92cfb06c2047fc2/tumblr_mn9jmhY0Le1sswo2do1_500.png

However the results is very weired. FFT happens with whole image and I cannot find the way.

Is it possible to seperate phase and add random noise for ONLY within-eclipse part?