Page 1 of 1
Laplacian Filter
Posted: Thu Oct 28, 2021 6:48 pm
by Scottk
In the layers module, how about adding a Laplacian filter? I knw the Sobel filter is there but adding a second order filter could provide more possibilities.
Re: Laplacian Filter
Posted: Sun Oct 31, 2021 12:00 am
by admin
Is this for edge detection/enhancement purposes? If so, would you find a Laplacian over Gaussian more useful?
Re: Laplacian Filter
Posted: Mon Nov 01, 2021 1:22 pm
by Scottk
Ivo,
Yes I am thinking about edge detection and enhancement. Please elaborate on how the Gaussian could be used. I would think that this would have the opposite effect.
Thanks.
Re: Laplacian Filter
Posted: Tue Nov 02, 2021 11:24 pm
by admin
Scottk wrote: ↑Mon Nov 01, 2021 1:22 pm
Ivo,
Yes I am thinking about edge detection and enhancement. Please elaborate on how the Gaussian could be used. I would think that this would have the opposite effect.
Thanks.
The problem with using a Laplacian filter alone is that the output is quite noisy and doesn't yield good/smooth edges. It is often combined with a Gaussian Filter.
I will implement this for the next beta.
In the meantime, also have a look at the Fractional Differentiation filter (
paper here) in the Layer module, which is much more useful for astronomical purposes (e.g. it is very adept at visualising structures that are otherwise very difficult to see).
Re: Laplacian Filter
Posted: Fri Nov 12, 2021 3:41 am
by admin
A Laplacian over Gaussian filter is now available in the Layer module in 1.8.519 beta. Any trouble, do let me know.