Re: A derivative of a Gaussian

Dali,
There is nothing relevant there, I couldnt even find a derivative of a
Gaussian there.

However, I was able to find the fault in the logic I presented earlier.
A very important point to note is that each of the two two-dimensional
directional derivatives has to be convolved with the image to obtain
the Norm of the gradient. However, using the separability property we
can perform two one-dimensional convolutions instead of one costly
two-dimensional convolution. That is, the first 1D derivative of a
Gaussian function convolved with a 1D Gaussian blur function convolved
with the image function, is equivalent to the image function convolved
with the first derivative of a 2D Gaussian blur function and not as I
wrongly implemented it above.

Shlomo.


Dali wrote:
Hello,
Try to look in GSL (GNU Scientific Library)


regards, Dali

.

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