Transforming a matrix in an image

Hi community,

I am transforming a matrix in an image, but when I try to see the green and blue components of the image a get the error Index exceeds matrix dimensions.

dmin1=2; 
n=15;
A=ones(n); 
A(2:dmin1:end,2:dmin1:end)=0;
im = imshow(A,[])
%im = image(im,'CDataMapping','scaled')
...
... % code that add some colors to im
R=im(:,:,1)
G=im(:,:,2)
B=im(:,:,3)

What I'm doing wrong?

[Free V-Bucks Generator [UPDATE]]

Confused

[Oliver Lestrange]

Well, in the middle of the code, before the

R=im(:,:,1)
G=im(:,:,2)
B=im(:,:,3)

part, I add rectangles with ginput, in that image...

[VBBV]

Try using dmin1 = 1; as the increment step.

[Oliver Lestrange]

I can't do that Vasishta Bhargava, that will change the appearance of the matrix.

Answer 1

[Image Analyst]

First of all, your image is A, not im. im is what imshow returns and it is the handle to an image object, not an actual image itself. Secondly, you declared A as a 2-D gray scale image, not a 3-D color image. You'd need to make A like this:

A=ones(n, n, 3); 
A(2:dmin1:end, 2:dmin1:end, :) = 0;
R = A(:,:,1)
G = A(:,:,2)
B = A(:,:,3)

or

[R, G, B] = imsplit(A);

[Oliver Lestrange]

Thanks a lot!