image restoration matlab code

조회 수: 122(최근 30일)
aziz alfares
aziz alfares 2021년 12월 2일
댓글: vaishnavi padhar 2022년 4월 13일
hello i am trying to implement this code to get the result in figure 5.26(b) but still something wrong could you help me in that
refernce: digital image processing gonzalez third edition
here is my code
c = im2double(imread('Fig0526(a)(original_DIP).tif'));
a = 0.1;
b = 0.1;
[M, N] = size(c);
h = zeros(M,N);
for u = 1:M
for v = 1:N
h(u,v) = (T/(pi*(u*a + v*b)))*...
sin(pi*(u*a + v*b))*...
exp(-1i*pi*(u*a + v*b));
c1 = cf.*h;
figure,imshow(abs(log(c1a)+1), []);

채택된 답변

Image Analyst
Image Analyst 2021년 12월 2일
The origin was not at the right place. Try this:
clc; % Clear the command window.
fprintf('Beginning to run %s.m ...\n', mfilename);
close all; % Close all figures (except those of imtool.)
clear; % Erase all existing variables. Or clearvars if you want.
workspace; % Make sure the workspace panel is showing.
format long g;
format compact;
fontSize = 15;
grayImage = im2double(imread('logo.tif'));
% Make sure it's 688 like the book says.
grayImage = imresize(grayImage, [688, 688]);
subplot(2, 3, 1);
imshow(grayImage, [])
axis('on', 'image')
title('Original Image', 'FontSize', fontSize)
% Make a filter for the spectral domain.
a = 0.1;
b = a;
[rows, columns] = size(grayImage);
h = zeros(rows, columns);
for u = 1 : rows
for v = 1 : columns
rx = v - columns/2;
ry = u - rows/2;
h(u,v) = (T/(pi*(ry*a + rx*b))) *...
sin(pi*(ry*a + rx*b))*...
exp(-1i*pi*(ry*a + rx*b));
% Print the max value of h.
absh = real(h);
fprintf('Max h = %f.\n', max(absh(:)))
subplot(2, 3, 2);
imshow(log(absh), []);
axis('on', 'image')
title('h Frequency Domain Filter', 'FontSize', fontSize)
% Compute fft of the image.
fftOrig = fftshift(fft2(grayImage));
subplot(2, 3, 3);
imshow(log(abs(fftOrig)), []);
axis('on', 'image')
title('FFT of original image', 'FontSize', fontSize)
% Multiply it by the filter. fftOrig and h have DC position at center of image.
c1 = fftOrig .* h;
% There are some nan's which mess up the inverse transform. Set nan's to zero.
rc = real(c1);
ic = imag(c1);
rc(isnan(rc)) = 0;
ic(isnan(ic)) = 0;
c1 = rc + 1i * ic;
subplot(2, 3, 4);
imshow(abs(log(c1)+1), []);
title('Filtered Spectrum', 'FontSize', fontSize)
% Inverse transform from frequency domain back to space domain.
% After multiplication, shift back.
c1Spatial = ifft2(ifftshift(c1));
subplot(2, 3, 5);
imshow(real(c1Spatial), []);
title('Filtered Image', 'FontSize', fontSize)
g = gcf;
g.WindowState = 'maximized'
  댓글 수: 2
vaishnavi padhar
vaishnavi padhar 2022년 4월 13일
can you please provide the code for inverse filtering

댓글을 달려면 로그인하십시오.

추가 답변(2개)

Image Analyst
Image Analyst 2021년 12월 2일
Why are you doing
exp(-1i*pi*(u*a + v*b));
??? Just use fft2().
  댓글 수: 1
aziz alfares
aziz alfares 2021년 12월 2일
the degradtion function as shown in (5.6-11) must be applied so i am trying to use the same equation to get the result

댓글을 달려면 로그인하십시오.

vaishnavi padhar
vaishnavi padhar 2022년 4월 13일
Can you please provide the block diagram for the same.




Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by