Subscripted assignment dimension mismatch.???

function [J] =  gabor_fn2(I)
clc; 
I=imread('e:\fingerprint3.jpg');
imshow(I); 
 I2 = imcrop(I); 
figure, imshow(I2) 
m=size(I2,1); 
n=size(I2,2); 
%%Gabor 
phi = 7*pi/8; 
theta = 2; 
sigma = 0.65*theta;
for i=1:3  
 for j=1:3 
      xprime= j*cos(phi); 
      yprime= i*sin(phi);   
    K = exp(2*pi*theta*sqrt(-1)*(xprime+ yprime)); 
      G= exp(-(i.^2+j.^2)/(sigma^2)).*abs(K);   
end 
end 

%%Convolve 
for i=1:m   
for j=1:n  
    J(i,j)=conv2(I2,G);   
end 
end 
figure,imshow(unit8(J))

Error in ==> gabor_fn2 at 26
    J(i,j)=conv2(I2,G);

Answer 1

[Wayne King]

The problem is that the output of conv2(I2,G) should be the same size as I2 the way that you have written the code.

In your code above, G, is a scalar, so you have constructed a for loop:

for ii=1:m 
    for jj =1:n 
        J(ii,jj)=conv2(I2,G); 
    end
end

that is convolving a matrix with a scalar.

For example:

G = 2;
x = randn(10,10);
size(conv2(x,G))

You cannot then assign this result to J(ii,jj). For example:

J(1,1) = conv2(x,G);

throws the error you are getting for the reasons I explained.