thanks, David
conference or vacation?
applied your statement

the result is an image with bands of pure (255) colors:

new infos for you (for me it's like Arabic...)
1-it seems that the execution part of the command only gets from the max fn a value 0,0,1 or 0,1,0 or 1,0,0 for the channels, so that the multiplier 255 transforms them into 0,0,255 or 0,255,0 or 255,0,0



2-if I replace 255*(i==max(R,G,B)) with (i=max(R,G,B)) it seems I get the correct max values but in greyscale



(strarting from this original)




hope this infos can help you...

Should work then.

yes, thanks!

David the magician of G'MIC...
You did in just one line what I did with tenths of lines, wonderful!
Excellent...

a new question to my friends

is there in G'MIC an equivalent of gimp "fuzzy borders"?
here an example:



but with some improvements:
1-the possibility to have just one fuzzy border, not all four
2-the possibility to have not a colour (white in the example) but transparency replacing the eroded part

Thanks

another (more general) question:
- is it possible from a G'MIC filter to call a "preview" of another G'MIC filter?
it's common to call from one filter another filter, but afaik one has to call it as an "execution" filter passing the required parameters;
my request is concerning the possibility to call the "preview" of the called filter, in order to have the parameters of the called filter prompted so that the user can choose among the parameters' options.
A sort of a "drill down" technique based on:
- a main filter where the user can select a "class" of options
- based on this selected class the main filter calls a "preview" of another filter, which is prompted to the user for the selection of a "specific" option inside the selected class
This possibility could allow to avoid writing filters with a looong list of parameters.
Thanks

Hello dinasset,
Sorry for not responding to your previous question, I didn't see it.
Concerning the previews : no, it is not possible for a G'MIC filter to make the user choose the parameter for a filter, then go back to another filter, and so on..
I really doubt this would be a desirable feature tough.
If one filter requires more than 10 parameters, it is already quite hard to use. So I don't imagine people want to use filters with more and more parameters.

For the framing effect, it looks that the command '-frame_fuzzy' may help in your case :

Thanks, David.
About the fuzzy frame I tried: it's excellent and flexible!.
About the other question I like to explain you better the need for such a "drill-down" selection:
- I'm trying to implement a filter which will have a parameter "colour"
- I like to give the user the possibility to choose the colour based on an "official" (standardized) colour name
- because the colours are a lot I was thinking about the possibility to have the main filter asking to choose only the colour category, for instance: "red colours"
- based on this choice I was hoping to have the possibility to "call" one among many slave filters, in this case the slave "red colours selection", where the list of the options will be of a reasonable size
Theoretically there are other possible solutions:
- one could be the possibility to have the list of the options "expandable", like the list of the filters in G'MIC itself, so that initially the user sees only the category then he/she may click on the category and expand the submenu
- another solution is to have two parameters the second of which is only "clickable" once the user has selected the first one and it is "linked" to that selection in order to "explode" itself accordingly
....
Probably in my previous post I did not explain properly the problem; I hate filters with many parameters, I consider them more or less totally "disturbing"; in my case the number of parameters is small, but the options list for one parameter is huge if there is no solution for a "drill-down" selection

Any hope?