Question

How to do this on matlab?

zero pad the face image with a five‐pixel
thick rim around the borders of the
image. show the resulting image.

Must be manual codes on script.

Answer 1

save this function as create_padded_image.m

function padded_image = create_padded_image(image, padding)

if nargin < 2
    % if no padding passed - define it.
    padding = 5;
end

if nargin < 1
    % let's create an image if none is given
    image = rand(5, 4)
end

% what are the image dimensions?
image_size = size(image);


% allocate zero array of new padded image
padded_image = zeros(2*padding + image_size(1), 2*padding + image_size(2))

% write image into the center of padded image
padded_image(padding+1:padding+image_size(1), padding+1:padding+image_size(2)) = image;

end

Then call it like this:

% read in image - assuming that your image is a grayscale image
$ image = imread(filename);
$ padded_image = create_padded_image(image)