Re: 7x7 and 9x9 Gaussian Convolution Kernel

On Fri, 5 Aug 2005 01:45:09 +0200, "Max" <adsl@xxxxxxxxxx> wrote:

>Hello!
>
>Could anyone write me a 7x7, 9x9 Gaussian convolution kernel with the
>coefficients are not zero and the sum of coefficients is equal to 256?
>How to calculate?

Assuming you want integer coefficients, I don't think your request is
possible: you're either going to have to accept some zeros -- since
Gaussian is not square -- or use floating point coeffs.

It's best to decompose gaussian two 1D convolutions, 7x1/1x7 or
9x1/1x9, in which case your desire can be met, and will be much faster
than a 2D linear filter.

Google this group for sample C code. I posted some a year or two ago.

--
Phillip Crews aka Severian
Microsoft MVP, Windows SDK
Posting email address is real, but please post replies on the newsgroup.
.

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