diff options
Diffstat (limited to '3176/CH4/EX4.18/Ex4_18.sce')
| -rw-r--r-- | 3176/CH4/EX4.18/Ex4_18.sce | 216 |
1 files changed, 108 insertions, 108 deletions
diff --git a/3176/CH4/EX4.18/Ex4_18.sce b/3176/CH4/EX4.18/Ex4_18.sce index 8a3e54776..ec3586868 100644 --- a/3176/CH4/EX4.18/Ex4_18.sce +++ b/3176/CH4/EX4.18/Ex4_18.sce @@ -1,108 +1,108 @@ -//Ex4_18
-//Image Smoothing Using Gaussian Lowpass Filter.
-// 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'gaussian'then
- H=exp(-(D.^2)./(2*(D0^2)));
- else
- disp('Unknownfiltertype.')
- end
-endfunction
-
-
-
-/////////////////////////////////// Main Programm ////////////////////////////////
-a=imread("Ex4_18.tif");
-//gray=rgb2gray(a);
-gray=im2double(a);
-
-figure,ShowImage(gray,'Gray Image');
-title('Original Image');
-[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)
-figure,ShowImage(inm,'Frequency Spectrum');
-title('Frequency Spectrum','color','blue','fontsize',4);
-
-/////////////////////////// Filtering With Cut-off Frequency 10 ///////////////////////
-filt=lowpassfilter('gaussian',M,N,10); // Function which generate Filter Mask Corresponding to Low Frequency
-//filt_shift=fftshift(filt);
-//figure,ShowImage(filt_shift,'Filter Mask');
-//title('Filter Mask to Specific Cut-Off Frequency');
-n=filt.*h;//Multiply the Original Spectrum with the Filter Mask.
-Image_filter=real(ifft(n));
-Image_filter=mat2gray(Image_filter)
-figure,ShowImage(Image_filter,'Filtered Image');
-title('Filtered Image with Cut-Off Frequency 10','color','blue','fontsize',4);
-
-
-/////////////////////////// Filtering With Cut-off Frequency 30 ///////////////////////
-filt=lowpassfilter('gaussian',M,N,30); // Function which generate Filter Mask Corresponding to Low Frequency
-//filt_shift=fftshift(filt);
-//figure,ShowImage(filt_shift,'Filter Mask');
-//title('Filter Mask to Specific Cut-Off Frequency');
-n=filt.*h;//Multiply the Original Spectrum with the Filter Mask.
-Image_filter=real(ifft(n));
-Image_filter=mat2gray(Image_filter)
-figure,ShowImage(Image_filter,'Filtered Image');
-title('Filtered Image with Cut-Off Frequency 30','color','blue','fontsize',4);
-
-
-/////////////////////////// Filtering With Cut-off Frequency 60 ///////////////////////
-filt=lowpassfilter('gaussian',M,N,60); // Function which generate Filter Mask Corresponding to Low Frequency
-//filt_shift=fftshift(filt);
-//figure,ShowImage(filt_shift,'Filter Mask');
-//title('Filter Mask to Specific Cut-Off Frequency');
-n=filt.*h;//Multiply the Original Spectrum with the Filter Mask.
-Image_filter=real(ifft(n));
-Image_filter=mat2gray(Image_filter)
-figure,ShowImage(Image_filter,'Filtered Image');
-title('Filtered Image with Cut-Off Frequency 60','color','blue','fontsize',4);
-
-
-/////////////////////////// Filtering With Cut-off Frequency 160 ///////////////////////
-filt=lowpassfilter('gaussian',M,N,160); // Function which generate Filter Mask Corresponding to Low Frequency
-//filt_shift=fftshift(filt);
-//figure,ShowImage(filt_shift,'Filter Mask');
-//title('Filter Mask to Specific Cut-Off Frequency');
-n=filt.*h;//Multiply the Original Spectrum with the Filter Mask.
-Image_filter=real(ifft(n));
-Image_filter=mat2gray(Image_filter)
-figure,ShowImage(Image_filter,'Filtered Image');
-title('Filtered Image with Cut-Off Frequency 160','color','blue','fontsize',4);
-
-
-/////////////////////////// Filtering With Cut-off Frequency 460 ///////////////////////
-filt=lowpassfilter('gaussian',M,N,460); // Function which generate Filter Mask Corresponding to Low Frequency
-//filt_shift=fftshift(filt);
-//figure,ShowImage(filt_shift,'Filter Mask');
-//title('Filter Mask to Specific Cut-Off Frequency');
-n=filt.*h;//Multiply the Original Spectrum with the Filter Mask.
-Image_filter=real(ifft(n));
-Image_filter=mat2gray(Image_filter)
-figure,ShowImage(Image_filter,'Filtered Image');
-title('Filtered Image with Cut-Off Frequency 460','color','blue','fontsize',4);
+//Ex4_18 +//Image Smoothing Using Gaussian Lowpass Filter. +// 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'gaussian' + H=exp(-(D.^2)./(2*(D0^2))); + else + disp('Unknownfiltertype.') + end +endfunction + + + +/////////////////////////////////// Main Programm //////////////////////////////// +a=imread("Ex4_18.tif"); +//gray=rgb2gray(a); +gray=im2double(a); + +figure,ShowImage(gray,'Gray Image'); +title('Original Image'); +[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) +figure,ShowImage(inm,'Frequency Spectrum'); +title('Frequency Spectrum','color','blue','fontsize',4); + +/////////////////////////// Filtering With Cut-off Frequency 10 /////////////////////// +filt=lowpassfilter('gaussian',M,N,10); // Function which generate Filter Mask Corresponding to Low Frequency +//filt_shift=fftshift(filt); +//figure,ShowImage(filt_shift,'Filter Mask'); +//title('Filter Mask to Specific Cut-Off Frequency'); +n=filt.*h;//Multiply the Original Spectrum with the Filter Mask. +Image_filter=real(ifft(n)); +Image_filter=mat2gray(Image_filter) +figure,ShowImage(Image_filter,'Filtered Image'); +title('Filtered Image with Cut-Off Frequency 10','color','blue','fontsize',4); + + +/////////////////////////// Filtering With Cut-off Frequency 30 /////////////////////// +filt=lowpassfilter('gaussian',M,N,30); // Function which generate Filter Mask Corresponding to Low Frequency +//filt_shift=fftshift(filt); +//figure,ShowImage(filt_shift,'Filter Mask'); +//title('Filter Mask to Specific Cut-Off Frequency'); +n=filt.*h;//Multiply the Original Spectrum with the Filter Mask. +Image_filter=real(ifft(n)); +Image_filter=mat2gray(Image_filter) +figure,ShowImage(Image_filter,'Filtered Image'); +title('Filtered Image with Cut-Off Frequency 30','color','blue','fontsize',4); + + +/////////////////////////// Filtering With Cut-off Frequency 60 /////////////////////// +filt=lowpassfilter('gaussian',M,N,60); // Function which generate Filter Mask Corresponding to Low Frequency +//filt_shift=fftshift(filt); +//figure,ShowImage(filt_shift,'Filter Mask'); +//title('Filter Mask to Specific Cut-Off Frequency'); +n=filt.*h;//Multiply the Original Spectrum with the Filter Mask. +Image_filter=real(ifft(n)); +Image_filter=mat2gray(Image_filter) +figure,ShowImage(Image_filter,'Filtered Image'); +title('Filtered Image with Cut-Off Frequency 60','color','blue','fontsize',4); + + +/////////////////////////// Filtering With Cut-off Frequency 160 /////////////////////// +filt=lowpassfilter('gaussian',M,N,160); // Function which generate Filter Mask Corresponding to Low Frequency +//filt_shift=fftshift(filt); +//figure,ShowImage(filt_shift,'Filter Mask'); +//title('Filter Mask to Specific Cut-Off Frequency'); +n=filt.*h;//Multiply the Original Spectrum with the Filter Mask. +Image_filter=real(ifft(n)); +Image_filter=mat2gray(Image_filter) +figure,ShowImage(Image_filter,'Filtered Image'); +title('Filtered Image with Cut-Off Frequency 160','color','blue','fontsize',4); + + +/////////////////////////// Filtering With Cut-off Frequency 460 /////////////////////// +filt=lowpassfilter('gaussian',M,N,460); // Function which generate Filter Mask Corresponding to Low Frequency +//filt_shift=fftshift(filt); +//figure,ShowImage(filt_shift,'Filter Mask'); +//title('Filter Mask to Specific Cut-Off Frequency'); +n=filt.*h;//Multiply the Original Spectrum with the Filter Mask. +Image_filter=real(ifft(n)); +Image_filter=mat2gray(Image_filter) +figure,ShowImage(Image_filter,'Filtered Image'); +title('Filtered Image with Cut-Off Frequency 460','color','blue','fontsize',4);
\ No newline at end of file |