Re: cross correlation and FFT problem

Is there any good examples (like commercial products or standards)
using the frequency domain for efficient convolution/filtering?

I guess that's what Bob's comment is about!?

Jens

I tend to agree with Bob's comment about doing convolution in the
frequency domain. Even though it's theoretically more efficient than
the time domain operation in certain cases I'm not familiar with any
practical implementations

On Wed, 28 Sep 2005 21:59:13 -0700, Bob Cain
<arcane@xxxxxxxxxxxxxxxxx> wrote:

>
>
>Jens Jørgen Nielsen wrote:
>> Hi,
>>
>> Be careful about the length of the FFT; you need a length at least the
>> sum of the lenghts of the two sequences minus one. The reason is that
>> the frequency domain operation is really a circular convolution.
>
>A rather useless operation IMHO. :-)
>
>
>Bob

.

Relevant Pages

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