@Wallace
Can You make this change?

Thank You in advance.

I noticed that the "desaturating" function in GEGL (Color to Gray) looks to have much more interesting results than the standard non-GEGL one.

Would be someone willing to write the "interface" (in python) so that it can be called from a python filter?
I think it would be very useful for filter writers...

If you want to try and experiment for yourself take a look over here: https://www.gimp-forum.net/Thread-Scrip ... operations

Otherwise I'll try and get to this next week.

Kevin

Thank Kevin.
Downloaded and had a look inside.
It creates an interface to 3 GEGL operations (waterpixel, slic, emboss), isn't it?
But I feel myself totally inadequate to add another one, like Color to Gray, to which I'm interested currently.
So I will wait for you having time next week to do it; that's a very generous offer. Thanks.

I've obviously not explained myself very well over on GimpForums

There's a python script that provides a scriptable interface to GEGL and an example script-fu to show how to use the python created pdb function.

Just to show how to do it, the script-fu actions those three GEGL functions in one go.

To use the python, you will need to know how to make command/parameter lists in the Filters>>Generic>GEGL Graph filter

...which is very complex.

But: does this mean that the one I pointed to (which is already a GEGL filter, Color to Gray) can't be subject to your same manipulation, being the 3 listed above GEGL function and not filters?
IIRC somewhere it's said that you need to look into the GEGL filter and indentify the needed parameters before creating properly the python interface.

To be more precise:
I have installed "gegl" unsharp mark, both the python pdb interface and the example calling scheme.
What I hope it could be done next week is the "same" for the "gegl" Color to Gray.

I'm not going to create a C2G specific script, so try this instead:


It's the code you need and an example script that does three actions, C2G, Softglow and Wind that illustrate some ways to build the GEGL Graph pipeline. This way you can easily add more GEGL actions to whatever code you are writing.

I make no claims that it will work on anything but Windows 10.

Thanks a lot, Kevin

Hi Kevin.

Great solutions.
Do you have a working example when it comes to choosing a color?
I am doing something very wrong because a tip from Massimo Valentini
,
does not help.

Started using the method kindly provided by Kevin for using GEGL.
Look here: viewtopic.php?f=11&t=18691&start=30
I like much more GEGL c2g !
Thanks again Kevin !

to specify a color you can use rgb(r,g,b) or rgba(r,g,b,a):


I recommend reading the information in the GEGL Graph dialog:


Kevin

A very good solution is presented on the website:
Samj Créations
https://samjcreations.blogspot.com/2020 ... -tres.html



If you want to use gegl_list_all (for me the slashes must be in the opposite direction) this is in the attachment.

@Kevin
Late thanks for the information provided

First tests....
The interesting thing about a plugin is that for it to work, you don't have to enter all its parameters - just the ones you want to change - and the rest are accepted by default.





If You are interested in parameter names and their range, you can find them in * .c files (in the appendix they come from Gegl Version: 0.4.24 - gegl\operations common).

I adapted the plug (a bit) to my needs:
Ver.2 - add: 80 operations, open the result as a layer, Preset in Notepad (separate entry in the menu: Filters/GEGL command & preset ...) with a list of operations (and to save by pasting versions of interesting settings).




Since the gegl.exe executable (Windows) is available in portable versions of Gimp from Samj Creation, but not in the official version of gimp.org - it is also included.
Why there are two fields for custom operations - to compare how changing a specific parameter affects the result (and keep the previous setting).

ps. Samj writes "Gegl_command_line.py" will likely be replaced by a C filter after Python 2 is abandoned.

Is this version callable from a main .py filter?
Does it return the result to the caller?
If yes, could you write a very small example as a guide?
Thanks!

Hi Diego.

Usage is simple:
- open any RGB photo *;
- run the plugin from the menu: Filters / GEGL command line ...;
- select the type of operation (80 standard +2 non-standard=Custom);
- select ExportType (PNG or JPEG);
- select how to open image (as a new layers or a new image);
- new images processed by Gegl are saved in the bin folder (and overwritten with);
- when you run ( Filters / GEGL & preset.txt command...) a document will open with a list of all operations and a link where you can find additional ones informations;
- in this I also save interesting settings for Custom;
- the record can be pasted into the plugin Command line GEGL (in Custom-1 or Custom-2)
- 80 operation is run without aditional parameters with default values ​​(there are many more operations in the documentation - but require additional parameters).

What you detailed is how to use it ONLINE
(2.point "run the plugin from the menu: Filters / GEGL command line ...")

I would like to run one filter written by me and -when a gegl operation is required- write something like
.....
outlayer=pdb.python_fu_gegl_command_line (inImage, inlayer, cmd string)
...
then do whatever next I need using outlayer produced by the gegl command line

Is it possible?

I answer to myself: YES !