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From: Ravi on 30 Mar 2010 00:17
hello.
i am doing a project on simply EYE DETECTION based on Ring Gabor Filter.
i have a problem in the following code in .
in this code i am not getting the output of for G.
code:
I = imread('k110.jpg');
I = rgb2gray(I);
I = imresize(I,[140,140]);
% imshow(I);
I=padarray(I,[50/2,50/2],'symmetric','both');
figure,imshow(uint8(I));
sx=3.7;
sy=8.0;
t=0;
F=4/256;
%F=0.117188;
for x=1:50
for y=1:50
x1=x*cos(t)+y*sin(t);
y1=-x*sin(t)+y*cos(t);
g(x1,y1)=(1.0/(2.0*3.14*sx*sy))*exp((-1.0/2.0)*((x1^2/sx^2)+(y1^2/sy^2)));
G(x,y)=g(x1,y1)*exp(F*sqrt(x^2+y^2)*2.0*3.14i);
end
end
figure,imshow((uint8(G)));



the formula for elliptical gabor filter is
G(x,y)=g(x',y') exp(2π jF x2+y2)........(1)
where
(x',y')=(xcosθ+ysinθ,−xsinθ+ycosθ) and F is
the spatial central frequency of the filter in the frequency
domain, g(x, y) is 2-D Gaussian envelope as follows:
g (x y)=(1/2*3.14*σx*σy)exp[(-1/2)*(((x^2)/σx^2)+((y^2)/σy^2))]
where σx and σy are variances (scale factors) along x and y
axes respectively. (x, y) is the center of the receptive field in
the spatial domain, θ is the rotation angle of the filter.

here i have used sx and sy instedof σx and σy &
t instead of θ...
here t=0;
sx=3.7;
sy=8.0;
t=0;
F=4/256;
this values are given in the rearch paper named """A new eye location method based on Ring Gabor Filter
Yanfang Zhang, Nongliang Sun, Yang Gao, Maoyong Cao
College of Information and Electrical Engineering
Shandong University of Science and Technology
Qingdao, 266510, China..."""
here i am not getting output of G.
where is my mistake...
Pleaz help me as soon as fast.
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