I’ve seen technical documentation for using / programming G’MIC itself but not for the filters. Obviously some of them are self explanatory, but equally obviously (to me at least!) many sliders / parameters are not clear… at least not to us who haven’t studied the underlying topic. In particular at the moment I’m interested in the usage of denoising and sharpening filters.
Have I overlooked it?
Thanks.
There is no consistent, project-wide documentation effort (or organized outcome from such) that covers the filters hosted by G’MIC-Qt plugin, comparable, say to the Technical Reference for the commands in the G’MIC scripting language. I’ve tried to be diligent with my tiny portfolio of filters (Finger Paint, Hedcut, Hair locks, Rectangular Tiling), but these are side effects of G’MIC tutorials; a few other filter authors have documented their filter controls, but in the main the G’MIC-Qt filters go undocumented. Many talented filter authors do not have English as their primary language. I guess the general feeling has been to get the filter itself in peoples’ hands first, niceties like documentation come later.
I think the best bet is to just post questions here about the filter, what you are trying to do with it and how the effort is falling short. If the filter author is active here on pixls.us, such a question will draw that worthy into the fray. Everybody takes pride in their creations, even if they lack time or language skills to write documentation. Failing that, I have been involved in a few efforts to decode the argument adapter portions of filters. That is a more light-weight endeavor than a full-blown filter dissection, so in the absence of a filter author, such decoding efforts may suffice.
That’s completely understandable. In my particular use case (at the moment) what I’m looking for has less to do with G’MIC and more to do with, for example, Richardson-Lucy, Ian’s Noise Reduction 2019 or whatever. I.e., what do all the sliders do (when it’s not self-evident).
As a result, there may be information of a more general sense elsewhere. I just want to use the tools as well as possible, which implies experimenting. That’s OK, but if there’s info that can help me avoid wasted time I’m all for it. 
Thanks.
Do you think you might be game for a little scripting? Computers are great for automating experimentation.
The gist of the idea may be found in the old Plasma Tutorial; scroll down to " Repeating Plasmas Using -srand" There’s a little squib of gmic command line interpreter code (CLI)
`gmic -repeat 5 -srand 123456 100,100,1,1 -plasma[-1] 1,'{$>}',6 -done -d -append x -n[-1] 0,255 -o[-1] betatest.png`
Except, in your case, you wouldn’t be using a blank image: 100,100,1,1, but input an image (or swatch) of something you want to study. And you wouldn’t be using plasma, but an fx_<some plugin adaptor> that constitutes the heart of the G’MIC-qt filter, and you might need to offset/scale the variable bit, {$>} to fit the parameter range of the filter.
I’m leaving out a boatload of practical nittie-gritties; just want to know if, in the main, you’re game. If you are, then I’ll walk you through the particulars.
I have the same issue. I just did a search on one of those filters and found a video on this site:
It is old, but may help you.
Another way is to scroll through the options panel, some authors put links to more help.
Searching more, I found Iain publishes his code at:
I hope this can point you in the right direction!
This looks like a very useful technique, one which I’ll put in my back pocket for the moment. I’m still very early on in my investigation but I may well come back and follow up with you. In a different universe as a unix admin before I retired I did LOTS of diagnostic and reference scripting, so the idea makes sense (even if the language doesn’t yet LOL).
Thanks for the offer and info!
Thanks for the info, I’ll check it out. Ideally it would be nice to completely handle denoising while raw-editing, but that may or may not work out.
Good info, thanks!
FYI, here’s some information on sharpening with R-L deconvolution vs. USM along with samples. I’ve not even read it yet but it looks interesting. I’ll get to it later.
https://clarkvision.com/articles/image-sharpening-intro/index.html