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| author | priyanka | 2015-06-24 15:03:17 +0530 |
|---|---|---|
| committer | priyanka | 2015-06-24 15:03:17 +0530 |
| commit | b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b (patch) | |
| tree | ab291cffc65280e58ac82470ba63fbcca7805165 /3176/CH4/EX4.17 | |
| download | Scilab-TBC-Uploads-b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b.tar.gz Scilab-TBC-Uploads-b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b.tar.bz2 Scilab-TBC-Uploads-b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b.zip | |
initial commit / add all books
Diffstat (limited to '3176/CH4/EX4.17')
| -rw-r--r-- | 3176/CH4/EX4.17/Ex4_17.sce | 112 | ||||
| -rw-r--r-- | 3176/CH4/EX4.17/Ex_4_17_2.jpeg | bin | 0 -> 50491 bytes | |||
| -rw-r--r-- | 3176/CH4/EX4.17/Ex_4_17_4.jpeg | bin | 0 -> 64108 bytes |
3 files changed, 112 insertions, 0 deletions
diff --git a/3176/CH4/EX4.17/Ex4_17.sce b/3176/CH4/EX4.17/Ex4_17.sce new file mode 100644 index 000000000..2e5966dd5 --- /dev/null +++ b/3176/CH4/EX4.17/Ex4_17.sce @@ -0,0 +1,112 @@ +//Ex4_17
+// Image Smoothing with a Butterworth 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'butterworth'then
+ if argn(2)==4 then
+ n=1;
+ end
+ H = ones(M,N)./(1+(D./D0).^(2*n));
+
+ else
+ disp('Unknownfiltertype.')
+ end
+endfunction
+
+
+
+/////////////////////////////////// Main Programm ////////////////////////////////
+a=imread("Ex4_17.tif");
+//gray=rgb2gray(a);
+gray=im2double(a);
+
+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)
+figure,ShowImage(inm,'Frequency Spectrum');
+title('Frequency Spectrum','color','blue','fontsize',4);
+
+/////////////////////////// Filtering With Cut-off Frequency 10 ///////////////////////
+filt=lowpassfilter('butterworth',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('butterworth',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('butterworth',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('butterworth',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('butterworth',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);
diff --git a/3176/CH4/EX4.17/Ex_4_17_2.jpeg b/3176/CH4/EX4.17/Ex_4_17_2.jpeg Binary files differnew file mode 100644 index 000000000..692c991cc --- /dev/null +++ b/3176/CH4/EX4.17/Ex_4_17_2.jpeg diff --git a/3176/CH4/EX4.17/Ex_4_17_4.jpeg b/3176/CH4/EX4.17/Ex_4_17_4.jpeg Binary files differnew file mode 100644 index 000000000..b40e63022 --- /dev/null +++ b/3176/CH4/EX4.17/Ex_4_17_4.jpeg |
