From 34de475999a22ac7280411e15339e77a0c8dbc2e Mon Sep 17 00:00:00 2001
From: Joe Zhao <ztuowen@gmail.com>
Date: Tue, 12 May 2015 13:15:55 +0800
Subject: initial commit

---
 filterNorm.m    |  3 +++
 gaborFilter.m   | 13 +++++++++++++
 gabor_example.m | 43 +++++++++++++++++++++++++++++++++++++++++++
 gabor_fn.m      | 27 +++++++++++++++++++++++++++
 genFeatureVec.m | 55 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 getVecs.m       | 26 ++++++++++++++++++++++++++
 parGetVecs.m    |  7 +++++++
 schmidFilter.m  |  5 +++++
 8 files changed, 179 insertions(+)
 create mode 100644 filterNorm.m
 create mode 100644 gaborFilter.m
 create mode 100644 gabor_example.m
 create mode 100644 gabor_fn.m
 create mode 100644 genFeatureVec.m
 create mode 100644 getVecs.m
 create mode 100644 parGetVecs.m
 create mode 100644 schmidFilter.m

diff --git a/filterNorm.m b/filterNorm.m
new file mode 100644
index 0000000..2037ae0
--- /dev/null
+++ b/filterNorm.m
@@ -0,0 +1,3 @@
+function fout = filterNorm(fin)
+    [x,y]=size(fin);
+    fout = fin-sum(sum(fin))/x/y;
\ No newline at end of file
diff --git a/gaborFilter.m b/gaborFilter.m
new file mode 100644
index 0000000..8cf9260
--- /dev/null
+++ b/gaborFilter.m
@@ -0,0 +1,13 @@
+function fout = gaborFilter(gamma,theta,lambda,sigma)
+    sigma_x = sigma;
+    sigma_y = sigma/gamma;
+
+    sz=fix(4*max(sigma_y,sigma_x));
+
+    [x y]=meshgrid(-sz:sz,sz:-1:-sz);
+
+    % Rotation 
+    x_theta=x*cos(theta)+y*sin(theta);
+    y_theta=-x*sin(theta)+y*cos(theta);
+
+    fout=filterNorm(exp(-0.5*(x_theta.^2/sigma_x^2+y_theta.^2/sigma_y^2)).*exp(2*i*pi/lambda*x_theta));
\ No newline at end of file
diff --git a/gabor_example.m b/gabor_example.m
new file mode 100644
index 0000000..88d0bc0
--- /dev/null
+++ b/gabor_example.m
@@ -0,0 +1,43 @@
+function gabor_example()
+% an example to demonstrate the use of gabor filter.
+% requires lena.jpg in the same path.
+% the results mimic:
+% http://matlabserver.cs.rug.nl/edgedetectionweb/web/edgedetection_examples
+% .html
+% using default settings (except for in radians instead of degrees)
+%
+% note that gabor_fn only take scalar inputs, and multiple filters need to
+% be generated using (nested) loops
+%
+% also, apparently the scaling of the numbers is different from the example
+% software at
+% http://matlabserver.cs.rug.nl
+% but are consistent with the formulae shown there
+lambda  = 8;
+theta   = 0;
+psi     = [0 pi/2];
+gamma   = 0.5;
+bw      = 1;
+N       = 8;
+img_in = im2double(imread('lena.jpg'));
+img_in(:,:,2:3) = [];   % discard redundant channels, it's gray anyway
+img_out = zeros(size(img_in,1), size(img_in,2), N);
+for n=1:N
+    gb = gabor_fn(bw,gamma,psi(1),lambda,theta)...
+        + 1i * gabor_fn(bw,gamma,psi(2),lambda,theta);
+    % gb is the n-th gabor filter
+    img_out(:,:,n) = imfilter(img_in, gb, 'symmetric');
+    % filter output to the n-th channel
+    theta = theta + 2*pi/N;
+    % next orientation
+end
+figure(1);
+imshow(img_in);
+title('input image');
+figure(2);
+img_out_disp = sum(abs(img_out).^2, 3).^0.5;
+% default superposition method, L2-norm
+img_out_disp = img_out_disp./max(img_out_disp(:));
+% normalize
+imshow(img_out_disp);
+title('gabor output, L-2 super-imposed, normalized');
\ No newline at end of file
diff --git a/gabor_fn.m b/gabor_fn.m
new file mode 100644
index 0000000..effc0ba
--- /dev/null
+++ b/gabor_fn.m
@@ -0,0 +1,27 @@
+function gb=gabor_fn(bw,gamma,psi,lambda,theta)
+% bw    = bandwidth, (1)
+% gamma = aspect ratio, (0.5)
+% psi   = phase shift, (0)
+% lambda= wave length, (>=2)
+% theta = angle in rad, [0 pi)
+ 
+sigma = lambda/pi*sqrt(log(2)/2)*(2^bw+1)/(2^bw-1);
+sigma_x = sigma;
+sigma_y = sigma/gamma;
+
+sz=fix(8*max(sigma_y,sigma_x));
+if mod(sz,2)==0, sz=sz+1;end
+
+% alternatively, use a fixed size
+% sz = 60;
+ 
+[x y]=meshgrid(-fix(sz/2):fix(sz/2),fix(sz/2):-1:fix(-sz/2));
+% x (right +)
+% y (up +)
+
+% Rotation 
+x_theta=x*cos(theta)+y*sin(theta);
+y_theta=-x*sin(theta)+y*cos(theta);
+ 
+gb=exp(-0.5*(x_theta.^2/sigma_x^2+y_theta.^2/sigma_y^2)).*cos(2*pi/lambda*x_theta+psi);
+imshow(gb/2+0.5);
\ No newline at end of file
diff --git a/genFeatureVec.m b/genFeatureVec.m
new file mode 100644
index 0000000..75fa0e8
--- /dev/null
+++ b/genFeatureVec.m
@@ -0,0 +1,55 @@
+function vec = genFeatureVec(img)
+    bins = 16;
+    ncnls = 8;
+    cnls = zeros(size(img,1), size(img,2),ncnls);
+    cnls(:,:,1:3) = img;
+    cnls(:,:,4:6) = rgb2ycbcr(img);
+    hsv = rgb2hsv(img);
+    cnls(:,:,7:8) = hsv(:,:,1:2);
+    % Schmid
+    scVec=[
+        1,2;
+        1,4;
+        2,4;
+        1,6;
+        2,6;
+        3,6;
+        1,8;
+        2,8;
+        3,8;
+        1,10;
+        2,10;
+        3,10;
+        4,10];
+    gbVec = [
+        0.3,0,4,2;
+        0.3,0,8,2;
+        0.4,0,4,1;
+        0.4,0,8,2;
+        0.3,pi/2,4,2;
+        0.3,pi/2,8,2;
+        0.4,pi/2,4,1;
+        0.4,pi/2,8,2;];
+    gb = length(gbVec);
+    sc = length(scVec);
+    vec=[];
+    for i = 1:sc
+        for cnl = 1:ncnls
+            filt = schmidFilter(scVec(i,1),scVec(i,2));
+            pos = real(sum(sum(filt.*(filt>0))));
+            neg = real(sum(sum(filt.*(filt<0))));
+            ss = (pos-neg)/bins;
+            v = histcounts(imfilter(cnls(:,:,cnl), filt, 'symmetric'),(0:bins)*ss+neg);
+            vec=cat(2,vec,v);
+        end
+    end
+    for i = 1:gb
+        for cnl = 1:ncnls
+            filt = gaborFilter(gbVec(i,1),gbVec(i,2),gbVec(i,3),gbVec(i,4));
+            pos = real(sum(sum(filt.*(filt>0))));
+            neg = real(sum(sum(filt.*(filt<0))));
+            ss = (pos-neg)/bins;
+            v = histcounts(real(imfilter(cnls(:,:,cnl), filt, 'symmetric')),(0:bins)*ss+neg);
+            vec=cat(2,vec,v);
+        end
+    end
\ No newline at end of file
diff --git a/getVecs.m b/getVecs.m
new file mode 100644
index 0000000..40f08cd
--- /dev/null
+++ b/getVecs.m
@@ -0,0 +1,26 @@
+function getVecs(dirname)
+    indir = strcat(strcat('~/VIPeR/',dirname),'/');
+    idlist=dir(indir);
+
+    ofile = strcat(dirname,'.txt');
+    fid = fopen(ofile,'wt');
+
+    for i=1:length(idlist)
+        n = idlist(i).name;
+        switch n
+            case '.'
+                continue;
+            case '..'
+                continue;
+            otherwise
+                n=n(1:strfind(n,'_')-1)
+        end
+        img=im2double(imread(strcat(indir,idlist(i).name)));
+        I=genFeatureVec(img);
+        fprintf(fid,'%s ',n);
+        fprintf(fid,'%f ',I);
+        fprintf(fid,'\n');
+    end
+    fprintf(fid,'0');
+    fclose(fid);
+end
\ No newline at end of file
diff --git a/parGetVecs.m b/parGetVecs.m
new file mode 100644
index 0000000..4097f5a
--- /dev/null
+++ b/parGetVecs.m
@@ -0,0 +1,7 @@
+parfor i=1:2
+    if i==1
+        getVecs('test_a');
+    else
+        getVecs('test_b');
+    end
+end
\ No newline at end of file
diff --git a/schmidFilter.m b/schmidFilter.m
new file mode 100644
index 0000000..12d4b30
--- /dev/null
+++ b/schmidFilter.m
@@ -0,0 +1,5 @@
+function fout = schmidFilter(t,sigma)
+    sz=fix(4*sigma);
+    [x,y] = meshgrid(-sz:sz,sz:-1:-sz);
+    r=sqrt(x.^2+y.^2);
+    fout = filterNorm(cos((2*pi*t/sigma)*r).*exp(-(r.^2)/(2*sigma^2)));
-- 
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