how to avoid 'index exceeds matrix dimension' error?

filter=[0.25 0.5 0.5 0.5 0.25;0.5 0.75 1 0.75 0.5;0.5 1 2 1 0.5;0.5 0.75 1 0.75 0.5;0.25 0.5 0.5 0.5 0.25];

for i=1:5 for j=1:5 filter(i,j)=filter(i,j)/16; end end

% Performs Smoothing

for v = 3 : m for u = 3 : n sum = 0; for i = -2 : 2 for j = -2 : 2 sum = sum + (I(u+i, v+j) * filter(i+3, j+3)); %here error occurs end end IDx(u,v) = sum; end end

Answer 1

[dpb]

filter=[0.25 0.5 0.5 0.5 0.25; ...
        ...
        0.25 0.5 0.5 0.5 0.25]/16;
% Performs Smoothing
for v= 3:m
  for u=3:n
    sum = 0; 
    for i = -2 : 2 
      for j = -2 : 2 
        sum=sum+(I(u+i,v+j)*filter(i+3, j+3)); %here error occurs
      end
    end
    IDx(u,v) = sum;
  end 
end

It's not in the filter subscripting so you've blown it w/ I

Having not provided any information for it or m, n, a precise answer isn't possible.

I'd suggest

doc filter2

[Idrees]

m & n are basically size of the input image 'I'.

[dpb]

So then

u+i>size(I,1) for i>0

and similarly for v+j

[Idrees]

is this smoothing can be achieved by conv2 function? if yes then how?