From f35ea80659b6a49d1bb2ce1d7d002583f3f40947 Mon Sep 17 00:00:00 2001 From: prashantsinalkar Date: Tue, 10 Oct 2017 12:38:01 +0530 Subject: updated the code --- 3176/CH4/EX4.20/Ex4_20.sce | 152 +++++++++++++++++++++------------------------ 1 file changed, 72 insertions(+), 80 deletions(-) (limited to '3176/CH4/EX4.20') diff --git a/3176/CH4/EX4.20/Ex4_20.sce b/3176/CH4/EX4.20/Ex4_20.sce index a193300fd..41226efb3 100644 --- a/3176/CH4/EX4.20/Ex4_20.sce +++ b/3176/CH4/EX4.20/Ex4_20.sce @@ -1,80 +1,72 @@ -//Ex4_20 -// Image Sharping in Frequency Domain Using the Laplacian -// Version : Scilab 5.4.1 -// Operating System : Window-xp, Window-7 -//Toolbox: Image Processing Design 8.3.1-1 -//Toolbox: SIVP 0.5.3.1-2 -//Reference book name : Digital Image Processing -//book author: Rafael C. Gonzalez and Richard E. Woods - -clc; -close; -clear; -xdel(winsid())//to close all currently open figure(s). - -function[H]=lowpassfilter(type1,M,N,D0,n)//lowpassfilter is used to filter an image . - u=0:(M-1); - v=0:(N-1); - idx=find(u>M/2); - u(idx)=u(idx)-M; - idy=find(v>N/2); - v(idy)=v(idy)-N; - [U,V]=meshgrid(v,u); - D=sqrt(U.^2+V.^2); - select type1 - - case'ideal'then - H=double(D<=D0); - - case'Laplacian'then - H_temp=double(D<=D0); - H=(4*(%pi)^2*D^2); - H=H.*H_temp; - - case'butterworth'then - if argn(2)==4 then - n=1; - end - H = ones(M,N)./(1+(D./D0).^(2*n)); - H_temp=ones(M,N)+(4*(%pi)^2*D^2); - H=H.*H_temp; - - case'gaussian'then - H=exp(-(D.^2)./(2*(D0^2))); - else - disp('Unknownfiltertype.') - end -endfunction - - - -/////////////////////////////////// Main Programm //////////////////////////////// -a=imread("Ex4_20.tif"); -//gray=rgb2gray(a); -gray=im2double(imresize(a,[540 540])); - -figure,ShowImage(gray,'Gray Image'); -title('Original Image','color','blue','fontsize',4); -[M,N]=size(gray); - -h=fft2(gray);//fft2() is used to find 2-Dimensional Fast Fourier Transform of an matrix -i=log(1+abs(h)); -in=fftshift(i);//fftshift() is used to rearrange the fft output, moving the zero frequency to the center of the spectrum. -inm=mat2gray(in); -filt=lowpassfilter('Laplacian',M,N,55); // User Define Function which generate Filter Mask Corresponding to Low Frequency -filt_shift=fftshift(filt); -n=filt.*h;//Multiply the Original Spectrum with the Filter Mask. -Image_filter=real(ifft(n)); -Image_filter=mat2gray(Image_filter); - -z=gray+Image_filter; -figure,ShowImage(mat2gray(z),'Filtered Image'); -title('Filtered Image with Specific Cut-Off Frequency','color','blue','fontsize',4); - - - - - - - - +//Ex4_20 +// Image Sharping in Frequency Domain Using the Laplacian +// Version : Scilab 5.4.1 +// Operating System : Window-xp, Window-7 +//Toolbox: Image Processing Design 8.3.1-1 +//Toolbox: SIVP 0.5.3.1-2 +//Reference book name : Digital Image Processing +//book author: Rafael C. Gonzalez and Richard E. Woods + +clc; +close; +clear; +xdel(winsid())//to close all currently open figure(s). + +function[H]=lowpassfilter(type1,M,N,D0,n)//lowpassfilter is used to filter an image . + u=0:(M-1); + v=0:(N-1); + idx=find(u>M/2); + u(idx)=u(idx)-M; + idy=find(v>N/2); + v(idy)=v(idy)-N; + [U,V]=meshgrid(v,u); + D=sqrt(U.^2+V.^2); + select type1 + + case'ideal' + H=double(D<=D0); + + case'Laplacian' + H_temp=double(D<=D0); + H=(4*(%pi)^2*D^2); + H=H.*H_temp; + + case'butterworth' + if argn(2)==4 + n=1; + end + H = ones(M,N)./(1+(D./D0).^(2*n)); + H_temp=ones(M,N)+(4*(%pi)^2*D^2); + H=H.*H_temp; + + case'gaussian' + H=exp(-(D.^2)./(2*(D0^2))); + else + disp('Unknownfiltertype.') + end +endfunction + + + +/////////////////////////////////// Main Programm //////////////////////////////// +a=imread("Ex4_20.tif"); +//gray=rgb2gray(a); +gray=im2double(imresize(a,[540 540])); + +figure,ShowImage(gray,'Gray Image'); +title('Original Image','color','blue','fontsize',4); +[M,N]=size(gray); + +h=fft2(gray);//fft2() is used to find 2-Dimensional Fast Fourier Transform of an matrix +i=log(1+abs(h)); +in=fftshift(i);//fftshift() is used to rearrange the fft output, moving the zero frequency to the center of the spectrum. +inm=mat2gray(in); +filt=lowpassfilter('Laplacian',M,N,55); // User Define Function which generate Filter Mask Corresponding to Low Frequency +filt_shift=fftshift(filt); +n=filt.*h;//Multiply the Original Spectrum with the Filter Mask. +Image_filter=real(ifft(n)); +Image_filter=mat2gray(Image_filter); + +z=gray+Image_filter; +figure,ShowImage(mat2gray(z),'Filtered Image'); +title('Filtered Image with Specific Cut-Off Frequency','color','blue','fontsize',4); \ No newline at end of file -- cgit