imfilter and filter2

Hi guys,

Are imfilter and fiter2 the same for two dimensional array?

I did a lot of experiment. It seems they are the same. But filter2 are much faster than imfilter

Thanks,

Zhong

Answer 1

[Wayne King]

Yes, they are the same in some instances:

    h = 1/100*ones(10,10);
    x = randn(20,20);
    y = filter2(h,x);
    y1 = imfilter(x,h);
    max(abs(y(:)-y1(:)))

but imfilter() gives more options to specify boundary conditions for example and whether to rotate the kernel or not -- 'corr' vs 'conv'