From b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b Mon Sep 17 00:00:00 2001
From: priyanka
Date: Wed, 24 Jun 2015 15:03:17 +0530
Subject: initial commit / add all books

---
 3176/CH5/EX5.8/Ex5_8.sce | 65 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 65 insertions(+)
 create mode 100644 3176/CH5/EX5.8/Ex5_8.sce

(limited to '3176/CH5/EX5.8/Ex5_8.sce')

diff --git a/3176/CH5/EX5.8/Ex5_8.sce b/3176/CH5/EX5.8/Ex5_8.sce
new file mode 100644
index 000000000..db4e987db
--- /dev/null
+++ b/3176/CH5/EX5.8/Ex5_8.sce
@@ -0,0 +1,65 @@
+//Ex5_8
+//Removal of Periodic Noise by Notch Filtering
+// 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]=notchfilter(M,N,W)//notchfilter is used to filter an image .
+        H=ones(M,N);
+        H(1:ceil(M/2-10),ceil(N/2-W/2):ceil(N/2+W/2))=0;
+        H(ceil(M/2+10):M,ceil(N/2-W/2):ceil(N/2+W/2))=0;    
+
+endfunction
+
+
+
+///////////////////////////////////   Main Programm   ////////////////////////////////
+a=imread("Ex5_8.tif");
+//gray=rgb2gray(a);
+gray=im2double(imresize(a,0.5));
+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');
+
+filt=notchfilter(M,N,3); // User Define Function which generate Filter Mask Corresponding to Low Frequency
+filt_pass=1-filt;
+//filt_shift=fftshift(filt);
+figure,ShowImage(filt,'Filter Mask');
+title('Filter Mask (Band stop) to Specific Cut-Off Frequency');
+
+n=filt.*fftshift(h);//Multiply the Original Spectrum with the Filter Mask.
+Image_filter=real(ifft(fftshift(n)));
+Image_filter=mat2gray(Image_filter)
+figure,ShowImage(Image_filter,'Filtered Image');
+title('Filtered Image with Specific Cut-Off Frequency');
+
+
+figure,ShowImage(filt_pass,'Filter Mask');
+title('Filter Mask (Band Pass) to Specific Cut-Off Frequency');
+
+n=filt_pass.*fftshift(h);//Multiply the Original Spectrum with the Filter Mask.
+Image_filter=real(ifft(fftshift(n)));
+Image_filter=mat2gray(Image_filter)
+figure,ShowImage(Image_filter,'Filtered Image');
+title('Filtered Image (Noise Pattern) with Specific Cut-Off Frequency');
+
+
+
+
+
+
-- 
cgit