walhad_cvip() - perform forward Walsh/Hadamard transform.



[ spect ] = walhad_cvip( input_img, block_size )

Input Parameters Include :

Output Parameters Include :


This function performs the Walsh/Hadamard transform of an input image. The Walsh/Hadamard transform uses rectangular function as the basis vectors. These vectors consist only of '1's and '-1's. This transform is easy to compute than Fourier and Discrete Cosine transforms. The function performs the WHT transform on the input image and zero pads the spectrum to the size of the block_size specified by the user.


1. Scott E Umbaugh. DIGITAL IMAGE PROCESSING AND ANALYSIS: Applications with MATLAB and CVIPtools, 3rd Edition.


% Read Image

 input_img = imread('Butterfly.tif');

% Block size

 block_size = 4;

% call function

 spect = walhad_cvip(input_img,block_size);

% Display input image

 figure;imshow(input_img);title('Input Image');

% Display output image

 figure;imshow(remap_cvip(log(1+abs(spect))),[]);title('Output Transformed Image');


Author: Mehrdad Alvandipour, July 2017
Copyright © 2017-2018 Scott E Umbaugh
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