Hi,
You can refer to the code below to apply Hadamard transform on the image.
% Load the PNG image
img = imread('img.jpg');
img = double(img);
% Resize the image to 256x256
lena = imresize(lena, [256,256]);
% Compute the Walsh-Hadamard Transform
wht = hadamard(256) .* lena .* hadamard(256)';
wht = wht / sqrt(256*256);
% Display the results
subplot(1,2,1);
imshow(uint8(lena));
title('Original Image');
subplot(1,2,2);
imshow(log(1+abs(wht)), []);
title('Walsh-Hadamard Transform');
Hope this helps!