GIMP Version: 2.8.14
Operating System: Windows
GIMP Experience: Basic Level

List any relevant plug-ins or scripts:
wavelet denoise (M.Rossini)

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wavelet denoise (M.Rossini)

I'm a bit curious about the use of this filter in a NON-INTERACTIVE mode, because the procedure browser shows the filter details WITHOUT ANY PARAMETER, while calling it interactively there are many and very interesting options.

Hence my questions:
1-why there is no detailed interface to this plug-in?
2-someone expert on it (Prokoudine?) could possible extend the interface to include the parameters available online? (I don't know the complexity of such a request...)
3-when called inside a script (w/o parameters), which are the defaults applied? (I ask this because some denoising effect is performed on the image)

Thanks

@Dinasset
I don't think the author ever intended this plug-in to be used non-interactively ..it is really only intended for interactive use ..you load-up a picture, decide you want to reduce the noise level, so you invoke "Wavelet denoise...", play around with the settings until the preview shows something you like, then hit OK or Cancel. That is the nature of the beast.

If you run it non-interactively, it should just use the same values as the last interactive use, the same as doing <Image>Filters>Repeat "Wavelet denoise..." (ie. for this plug-in RUN-NONINTERACTIVE is the same as RUN-WITH-LAST-VALS).

Having said that, if there is a genuine case for using it non-interactively, it should not be too difficult to upgrade - all the denoising parameters are stored in a simple data structure which is stored by Gimp between invocations (using gimp_set_data() and gimp_get_data() ) the same as all other C plug-ins, and it should therefore be a relatively straightforward matter to set those values from user-supplied parameters when called non-interactively.

There is a smooth [wavelets] filter in G'MIC that's probably a bit more powerful than the plug-in. Might be an option for you to call non-interactively from a script.

thanks, jontait2
do you mean that -in case I want to experiment using that filter in a .scm script- I can make use of "gimp-procedural-db-get-data" and "gimp-procedural-db-set-data"?
But in this case what sequence of data do I retrieve/put?
I don't know the data structure (string) of that filter, also I don't know about C code, I just write my scripts in .scm (sometimes .py)
So, I guess, for a very basic script-writer like me, I have to wait on an enhanced version of that filter...

Yes, thanks Gnutux, I know about that G'MIC filter, it's nice.
But I'm always jumping forth and back from gimp to gmic, so I am curious why the author (and/or any susequent maintainer) did not think about a use in a non-interactive way...It's a good gimp filter and if someone wants to write a script which performs many image enhancements and among those a wavelet denoising, why not?

No!
The gimp_set_data() and gimp_get_data() are libgimp functions used by C plug-ins to store and retrieve data, including run parameters. Nothing to do with PDB data, so you can't use those PDB procedures to access/change the values used by a plug-in.
What I meant was that we could enhance the "Wavelet denoise" plug-in to accept parameters in NONINTERACTIVE mode. But that means amending the source and building for the various platforms (Linux, Windows, etc).

BTW what operating system are you using?

Windows 7 - 32bits

I'm going to possibly disagree with you, mostly because you seem to have miss-read what dinnaset wrote: gimp-procedural-db-get-data not gimp_get_data()

This is what gets returned after running wavelet-denoise with default settings:

All you have to do is decode all 136 numbers into the values passed in

I've been experimenting with the Refocus plug-in (less parameters) and I can change the last remembered values using gimp-procedural-db-set-data

I have yet to work out the encoding.

I do however agree that the best option is to modify wavelet-denoise so that it can be run interactively, although I question whether it's sensible to run interactively as that implies batch processing and noise reduction is very subjective and "best" settings will vary between images.

Kevin

Here is a script to call G'MIC's Smoothing [wavelets] non-interactively. I've included the first 3 parameters in a script-fu dialog for demonstration purposes. Maybe you will find this useful.

thanks Kevin
should I be one day enough relaxed to "understand" all that bulk of numbers and try to modify the string using the "set", I'll post here my tests

Thanks Gnutux for your input.
I wrote already a script using G'MIC wavelet, it works fine.
As I said I was willing to try Gimp...

Oh, OK. Sorry, I misunderstood. I just thought you needed to run a wavelet filter non-interactively from a script and G'MIC seemed like a good option, since it's already there. Never like to re-invent the wheel.

I appreciate your help, Gnutux! Don't be sorry, I didn't say before I wrote already using G'MIC, I only said I knew it; that's the origin of the misunderstanding.
I'm still working on that Gimp-G'MIC filter, because denoising is just part of my goal: enhancing a photo under various aspects (I'm normally lazy, but also ambitious from time to time...hehehe!).
The whole thing will take long...

Kevin, this morning a made a little test:
1-run the filter setting threshold to 10 and softness to 1
2-entered into the script-fu console the command
(gimp-procedural-db-get-data "plug-in-wavelet-denoise")
3-stored the output into a text file
4-run again the filter setting threshold to 5 and softness to 0.5
5-entered again the command into the console
6-appended the output into the previous text file
7-compared the two outputs

I hoped to find just two differences, related to the two parameters changed.
No, the differences are a lot, and the input values are not recognizable, at least for me

these are the data:


hence I will certainly not continue on this way
should some expert modify the code of the plug-in so that it can be called non-interactively with the same parameters available online, well
otherwise I will stay with my G'MIC wavelet denoise filter

dinasset:

My experimenting yesterday leads me to the conclusion that the float values are being stored as double precision binary floats:- which are 8 bytes each.

For plug-in-refocus:


See: http://www.binaryconvert.com/convert_double.html

Kevin

thanks Kevin
this important info could lead me to do some other experiment...

@Dinasset
The data stored by "plug-in-wavelet-denoise" is defined thus:

So the data you retrieved with your second use of (gimp-procedural-db-get-data "plug-in-wavelet-denoise") corresponds like this:

The gray_threshold[] and gray_low[] values are for GRAY images and only the first value is actually used at present (as far as I can see).
The colour_threshold [] and colour_low[] values correspond to the colour channels shown in the dialog and are therefore dependent upon the colour_mode.
Note: the "low" values correspond to the "Softness" setting in the dialog.

So you can use (gimp-procedural-db-get-data ) to set the parameters if you want to, but this is a pretty obtuse way of doing it. You will still have to convert float values to bytes.

If you want to do it the "proper" way, here is a hacked version of the plugin source which accepts parameters in
NONINTERACTIVE mode:
You can see the parameters listed in the Procedure Browser.

I've run this on Linux and it seems to work okay, but I cannot build it for Windows at the moment (my MINGW environment is broken ..must sort it out).
Perhaps somebody else (eg. Rod or Graechan) can build it for Windows 32bit.

Like Kevin, I'm still doubtful of the merits of trying to use this filter non-interactively.
Sounds a bit like .. http://xkcd.com/1503/

many thanks jontait2, both for the info (which I can try to use...) and for the revised filter (for which I need to wait an .exe compiled for win 32)

let me say, I don't understand why this filter shouldn't be used in a script, if it is because you think the user should see interactively how the parameters changes act on the image, that's something true for the majority of the filters
(note that the equivalent G'MIC filter can be used inside a script)

No, the point is that, for any given image, you really only get the best results thru judging by eye the best settings for each color channel .. and there are considerable differences between images.
So, unless you have lots of images with exactly the same contrast/levels/exposure/color settings/etc it's difficult to see how using this filter non-interactively is going to produce useful results.

correct, but you have the same difficulty with a lot of many other filters manipulating the "appearance" of the pixels in the image...
a reasonable script should define the parameters at a much higher level, for the common user, for instance:
- requested intensity of the denoising action: low, moderate, high...
and the filter should be able to translate into internal values which can reasonably provide an average good (=as expected) result for an amateur
then, the interactive filter is always there for the real photographers