[GRASS-user] adaptive gaussian filter

GRASS GRASS user
1

Hi all,

I would like to ask, whether there is a code or extension, which would
apply gaussian filtering on raster data, but with varying sigma value
according to one of input raster maps?

I would like to blur raster but differently on different regions (e.g.
based on texture characteristics)

Thank you

Jachym

--
Jachym Cepicky
e-mail: jachym.cepicky gmail com
URL: http://les-ejk.cz
GPG: http://les-ejk.cz/pgp/JachymCepicky.pgp

2

Something like anisotropic diffusion described by Perona P. and Malik
J. 1990? https://en.wikipedia.org/wiki/Anisotropic_diffusion
I do have a working C module performing aforementioned noise reduction
(with optional Tukey's conductance function according to Black et al.
1998) but I haven't found time (and need) to clean it up + write
documentation to make it production ready. If you are working on a
publication where it would be useful, I'm in.

Māris.

Perona P. and Malik J. 1990. Scale-space and edge detection using
anisotropic diffusion. IEEE transactions on pattern analysis and
machine intelligence, 12(7).
Black M.J., Sapiro G., Marimont D.H. and Heeger D. 1998. Robust
anisotropic diffusion. IEEE transactions on image processing, 7(3).

trešd., 2020. g. 29. jūl., plkst. 14:22 — lietotājs Jachym Cepicky
(<jachym.cepicky@gmail.com>) rakstīja:

Hi all,

I would like to ask, whether there is a code or extension, which would
apply gaussian filtering on raster data, but with varying sigma value
according to one of input raster maps?

I would like to blur raster but differently on different regions (e.g.
based on texture characteristics)

Thank you

Jachym

--
Jachym Cepicky
e-mail: jachym.cepicky gmail com
URL: http://les-ejk.cz
GPG: http://les-ejk.cz/pgp/JachymCepicky.pgp
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3

Interesting, thanks for the hint

J

st 29. 7. 2020 v 14:24 odesílatel Maris Nartiss <maris.gis@gmail.com> napsal:

Something like anisotropic diffusion described by Perona P. and Malik
J. 1990? https://en.wikipedia.org/wiki/Anisotropic_diffusion
I do have a working C module performing aforementioned noise reduction
(with optional Tukey's conductance function according to Black et al.
1998) but I haven't found time (and need) to clean it up + write
documentation to make it production ready. If you are working on a
publication where it would be useful, I'm in.

Māris.

Perona P. and Malik J. 1990. Scale-space and edge detection using
anisotropic diffusion. IEEE transactions on pattern analysis and
machine intelligence, 12(7).
Black M.J., Sapiro G., Marimont D.H. and Heeger D. 1998. Robust
anisotropic diffusion. IEEE transactions on image processing, 7(3).

trešd., 2020. g. 29. jūl., plkst. 14:22 — lietotājs Jachym Cepicky
(<jachym.cepicky@gmail.com>) rakstīja:
>
> Hi all,
>
> I would like to ask, whether there is a code or extension, which would
> apply gaussian filtering on raster data, but with varying sigma value
> according to one of input raster maps?
>
> I would like to blur raster but differently on different regions (e.g.
> based on texture characteristics)
>
> Thank you
>
> Jachym
>
> --
> Jachym Cepicky
> e-mail: jachym.cepicky gmail com
> URL: http://les-ejk.cz
> GPG: http://les-ejk.cz/pgp/JachymCepicky.pgp
> _______________________________________________
> grass-user mailing list
> grass-user@lists.osgeo.org
> https://lists.osgeo.org/mailman/listinfo/grass-user

--
Jachym Cepicky
e-mail: jachym.cepicky gmail com
URL: http://les-ejk.cz
GPG: http://les-ejk.cz/pgp/JachymCepicky.pgp