An un-sharp masking is used for enhancing the edges in an image. The method is to subtract an un-sharp version of the image from the original image with suitable weighting, that is g(m,n)=f(m,n)*h(m,n) (* = convolution) where: g(m,n)=af(m,n)-[ f(m-1,n)+f(m+1,n)+f(m,n-1)+f(m,n+1)]

Where f(m,n) is the original image.

1. Calculate the transfer function for the filter, for example: the DTFT (Discrete Time Fourier Transform) H(u,v) of the impulse response h(m,n) for a=2. 2. Plot |H(u,v)| for relevant frequency span. Explain your choice of span

m, n represent x,y co-ordinates. e,g f(x,y).