[Matrix-SIG] general 2D convolution, again.

David Buscher David.Buscher@durham.ac.uk
Fri, 27 Mar 1998 11:15:44 +0000 (GMT)

On Thu, 26 Mar 1998, David Ascher wrote:

> Problem: doing 2D convolutions with non-square and different shape arrays
> is (from what I've read) not doable using FFT multiplication.

I believe this is something of an oversimplification. All convolutions 
are doable using an FFT, providing you pad the arrays with zeros to a 
mutually compatible size, and perhaps add extra padding to take care of 
edge effects. The only question then is whether this is the most 
efficient way to do the computation, which is clearly an 
implementation-dependent topic. Someone please correct me if I'm wrong!

 David Buscher                          |  Phone  +44 191 374 7462
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