Assign value to a circular mask

Question

X 2014-8-14

回答： Dishant Arora 2014-8-14

Hi everyone,

I used the following code to generate a circle mask located at [cX, cY] on a 500 by 500 "film":

cX=200; cY=100; r=30; % radius of the circle width=500; height=500;

[W,H]=meshgrid(1:width, 1:height); mask=sqrt((W-cX).^2+(H-cY).^2)<=r; imshow(mask) colorbar

But for now the circle value = 1, and the rest of the film value = 0; How can I assign specific value (for instance, 5) to the circle value?

Thank you! Sonia

Answer 1

Dishant Arora 2014-8-14

Use logical indexing.

circDisk = double(mask); % Converting mask to the type double
circdisk(mask) = 5 % or whatever value you want.