matlab实现gabor filter (10) 效果很好

gabor 滤波器 函数：

 

function [GaborReal, GaborImg] = MakeGaborKernal(GaborH, GaborW, U, V, Kmax,f,sigma )
% function [GaborReal, GaborImg] = MakeGaborKernal[GaborH, GaborW, U, V]
% 用以生成 Gabor 核
% GaborReal: 核实部 GaborImg: 虚部
% GaborH,GaborW: Gabor窗口 高宽.
% U,V: 方向 大小
%            ||Ku,v||^2
% G(Z) = ---------------- exp(-||Ku,v||^2 * Z^2)/(2*sigma*sigma)(exp(i*Ku,v*Z)-exp(-sigma*sigma/2))
%          sigma*sigma

HarfH = fix(GaborH/2);
HarfW = fix(GaborW/2);

Qu = pi*U/8;
sqsigma = sigma*sigma;
% Kv = 2.5*pi*(2^(-(V+2)/2));
Kv = Kmax/(f^V);
 
postmean = exp(-sqsigma/2);

for j = -HarfH : HarfH
    for i =  -HarfW : HarfW
      
        tmp1 = exp(-(Kv*Kv*(j*j+i*i)/(2*sqsigma)));
        tmp2 = cos(Kv*cos(Qu)*i+Kv*sin(Qu)*j) - postmean;
  %      tmp3 = sin(Kv*cos(Qu)*i+Kv*sin(Qu)*j) - exp(-sqsigma/2);
        tmp3 = sin(Kv*cos(Qu)*i+Kv*sin(Qu)*j);
       
        GaborReal(j+HarfH+1, i+HarfW+1) = Kv*Kv*tmp1*tmp2/sqsigma;
        GaborImg(j+HarfH+1, i+HarfW+1) = Kv*Kv*tmp1*tmp3/sqsigma;
    end
end

调用代码：

 

% GaborReal, [GaborH,GaborW,40] 40个Gabor模板实部
% GaborImg,  [GaborH,GaborW,40] 40个Gabor模板虚部
% 缺省输入前2个参数,后面参数 Kmax=2.5*pi/2, f=sqrt(2), sigma=1.5*pi;
% GaborH, GaborW, Gabor模板大小
% U,方向因子{0,1,2,3,4,5,6,7}
% V,大小因子{0,1,2,3,4}
% Kmax,f,sigma 其他参数

GaborH=31;
GaborW=31;
Kmax=2.5*pi/2;
f=sqrt(2);
sigma=1.5*pi;
    
GaborReal = zeros( GaborH, GaborW, 40 );
GaborImg = zeros( GaborH, GaborW, 40 );

vnum=5;
unum=8;

% 获得滤波器组
for v = 0 : (vnum-1)
    for u = 0 : (unum-1)
        [ GaborReal(:,:,v*8+u+1), GaborImg(:,:,v*8+u+1) ] = MakeGaborKernal( GaborH, GaborW, u, v, Kmax,f,sigma );
    end
end


G=cell(5,8);
for i = 1:5
    for j = 1:8
        G{i,j}=zeros(GaborH,GaborW);
    end
end

for i = 1:5
    for j = 1:8
        G{i,j}=GaborReal(:,:,(i-1)*8+j);
    end
end

%plot
figure;
for i = 1:5
    for j = 1:8
        subplot(5,8,(i-1)*8+j);        
        %imshow(real(G{s,j})/2-0.5,[]);
        imshow(real(G{i,j}),[]);
    end
end

 

生成的滤波器组图像：