Image Grey to Color

Hi there, I am trying to perform certain task on the image:

In which I should divide it into three equal parts, then extract the RGB planes seperately and fuse all of them in a one color image:

img = imread('image.jpg');
[h, w] = size(img);
h_one = h / 3;
B = imcrop(img,[1, 1, w, h_one]);
G = imcrop(img,[1, 1*h_one, w, h_one]); 
R = imcrop(img,[1, 2*h_one, w, h_one]); 
colorImg(:,:,1) = R;
colorImg(:,:,2) = G;
colorImg(:,:,3) = B;
imshow(colorImg)

but the grader of the course doesn't accept it and tells me: Variable B must be of size [341 400]. It is currently of size [342 400], and I don't know to to handle it.

The result image:

[Rena Berman]

(Answers Dev) Restored edit

Answer 1

[Walter Roberson]

B = imcrop(img,[1, 1, w, h_one]);

What is the first row number that will be extracted when you do that? What is the last row number that will be extracted when you do that?

G = imcrop(img,[1, 1*h_one, w, h_one]); 

What is the first row number that will be extracted when you do that? What is the last row number that will be extracted when you do that?

Is the black border extracted above the top image the same height as the black border extracted above the middle image?

Is the black border extracted below the bottom image the same height as the black border extracted below the middle image?