I found:

1. Smart Sharpening, Redux version, by Martin Egger.
2. Smart Sharpen by Paul Harrison, that uses the resynthesizer plugin
3. Luminocity Sharpen by Olli Salonen
4. SmartSharpening by Diego

Olli Salonen's Luminocity Sharpen (<Image>/FX-Foundry/Photo/Sharpen/Luminocity Sharpen) , gives a similar result, I think.
http://www.trsqr.net/photokit/ss.html (website Olli Salonen)

Finished the look into: yes, there is a Smart Sharpen script among those from Japan.
Probably what I remembered.
Thanks

Here it is, in case someone likes to test it:

Dinasset, Olli Salonen refers to the same tutorial in his script.

With your script, the image is smoother (less noisy) and can scale, so it is something different. Maybe you can make the smoothing adjustable?

The original gimp tutorial refers to this photoshop tutorial (John Brownlow):
https://luminous-landscape.com/smart-sharp/

Now I see, this ps tutorial is hidden behind a paywall. The first time I got the whole tutorial, strange.

iarga, are you saying that my outcome is "too" smooth?
or simply "smoother" than Olli's.
I did apply a smooth indeed, to get rid of noise.

Assuming you wanted to say "too" smooth, I reduced the smoothing step.
I posted the update.

Dinasset, I didn't say "too smooth". I think that's a matter of taste. Actually I like the smoothing step. Therefore I asked you if you could make the smoothing adjustable (with a slider?). Your filter doesn't have tot be the same as the filter made by Salonen.

OK, but what do you think of the update?
Is it still enough smooth to be scaled?

With scaling, I prefer, without a doubt, your first filter, the smooth one.

Without scaling, I like both filters or a combination from both of them. It depends on what I want to achief.

Thanks.

I like your results, Pat.

Thanks Pat and Issabella.
I've prepared a new release with the possibility for the user to enter/modify the intensity of the sharpen and the smooth steps (last one as requested by iarga).
All friends can perform tests on this version and tell me their comments.


iarga, is it OK how it is now? (I added the possibility to customize also the sharpening amount)

This is with your newest version.

Dinasset, very nice filter. With everything I recommended (and more). Thank you very much.

Thanks a lot Pat and iarga.
I'm happy you like the filter, iarga. Hope you can use it with benefits for your photos.

Pat, your cat&bird is a very nice image and filter's outcome.

Thank you, Dinasset. You have another very fine script for us to use.