Hi, I have typed: " sudo apt-get install git build-essential libgimp2.0-dev libcv-dev libopencv-dev \
libhighgui-dev libcurl4-openssl-dev libfftw3-dev qt5-default qtbase5-dev" but I have these errors:

" The libhighgui-dev package has no versions available, but is named by another
package. This could indicate that the package is missing, obsolete
or is available only within another source
However, these packages replace it:
libopencv-dev: i386 libopencv-dev

The libcv-dev package has no versions available, but is named by another
package. This could indicate that the package is missing, obsolete
or is available only within another source
However, these packages replace it:
libopencv-dev: i386 libopencv-dev

E: The "libcv-dev" package has no candidate to install
E: The "libhighgui-dev" package has no candidate to install ".
I have also downloaded the .zip archive for gimp 2.10 for linux but I have a file named gmic_gimp_qt but I don't know what to do (I went to the file's folder and typed: "make gimp " but I got an error message saying: "No rules to generate the "gimp" goal. Stop.".
The Gimp version that I have is installed from flatpack, the G'MIC plugin availlable in the repositories is for Gimp 2.8.
Please help because I really don't know what to do.
Thanks in advance

1. You are using the Gimp 2.10 flatpack. You can not use that for compiling gimp plugins

2. You are using the Gimp 2.10 flatpack. That does not support QT applications. gmic_gimp_qt will not work

Alternatives to the flatpack.

Gimp 2.10.10 from the PPA see https://launchpad.net/~otto-kesselgulas ... buntu/gimp for details about adding to the repo.

Then get the gmic_gimp_qt plugin from https://gmic.eu/files/linux/gmic_gimp2. ... _amd64.zip Unzip, put in ~/.config/GIMP/2.10/plug-ins
Lots of dependencies so run Gimp from a terminal with the --verbose switch to see what you need. typically libcurl, libfftw3, libqt5core* libqt5widgets5* there might be more.

or

Use an appimage: https://github.com/aferrero2707/gimp-appimage/releases/ there are plugins including gmic for that https://github.com/aferrero2707/gimp-pl ... continuous
The snag I found (apart from unpacking several thousand files to /tmp every use) is it is not totally compatible with Ubuntu. It is very good, but first time I used one of my own plugins it would not run it.

I've found the only way I can get G'mic to work in the PPA running LM 19.1, is to use the G'mic DEB installer version for Ubunto 18.04 : https://gmic.eu/files/linux/gmic_ubuntu ... _amd64.deb

Remove any gmic_gimp_qt you may have in the Plug-ins folder 1st. This will install G'mic system-wide.

I unpacked that deb just to see the gmic_gimp_qt plugin. Seems to work but the title bar does say for Gimp 2.8

If you want just the gimp plugin for Gimp 2.10, I keep one here: https://www.gimp-forum.net/Thread-gmic- ... untu-18-04

It is specifically for 18.04 because of the 18.04 QT version but it does work, at least on a 'buntu 19.04 I was installing for someone just on Friday. The only drawback are the number of dependencies required on a 'minimal' 'buntu 19.04 installation.

Yes, you are correct, in that it does say "Gimp 2.8", but rest assured it works perfectly well in Gimp 2.10.10 at the moment....

No idea why it does this, but it does for all the "DEB" installers. Maybe a hacked version? I don't know.

The solution given by rich2005 (to download the package from the gimp forum) worked for me.
Thanks a lot

@rich2005, Yes your compiled version works perfectly. Thanks for doing the work. We now have at least two working options for LM19.x on Otto's PPA.

I really should learn to compile my own, but it's a little beyond my geek level.