what does this do r = img1(:,:,1); % red channel g = img1(:,:,2); % green b = img1(:,:,3);

r = img1(:,:,1);

g = img1(:,:,2);

b = img1(:,:,3);

Answer 1

[Wayne King]

That is taking an RGB image, img1, and extracting the red, green, and blue parts and creating 3 2-D matrices: r,g, and b.

An RGB image, sometimes referred to as a truecolor image, is stored in MATLAB as an M-by-N-by-3 data array that defines red, green, and blue color components for each individual pixel. RGB images do not use a palette. The color of each pixel is determined by the combination of the red, green, and blue intensities stored in each color plane at the pixel's location.

[Prasad MV]

thank you. . .

can you tell me what does this means. .

repmat(okpxls, [1, 1, 3]);

and

zeros(size(img), class(img));

pls reply asap. .

[Wayne King]

repmat(okpxls,[1 1 3]) replicates (copies) an input into 3-D.

x = randn(3,1);

y = repmat(x,[1 1 3]);

zeros(size(img), class(img));

creates a matrix of zeros the same size and class as image

x1 = uint8(randn(8,8));

x2 = zeros(size(x1),class(x1));