Processing or editing an image is not easy if you do not have the right skill and tools for that. The Gimp can be your ally. GIMP is an acronym for GNU Image Manipulation Program.
Customization: since it is a free software downloading the source code is possible, users can modify it according to their needs. One can for example customize the GUI or hide certain features for other users.
Photo editing: it has all the necessary tools to enhance and edit photos. Indeed, you can eradicate distortions of an image when shooting, as well as thumbnails. Also it is possible to work with files in jpeg, gif, bmp, png and more.
Image: this photo editing program is integrated with the tools for cloning or for cleaning. It is possible to use a mouse pen/tablet for details during the handling. Connecting Midi control surfaces is also possible. Simply choose the features you want to assign to each button.
The Gimp is downloadable free of charge.
It has all the basic tools for photo editing.
It uses MIDI controllers for better control.
GUI very well designed.
Getting started is quite tedious at first, requires time to adapt.