Open Source Photo Editing Software
Phototonic
Phototonic is a fast and functional, open source image viewer and organizer. The software is written in C++/Qt and released for free under GNU General Public License v3. Phototonic takes inpiration from traditional image views and provides overview of your inventory with thumbnails and organized layouts.
ImageGlass
ImageGlass is a lightweight, versatile image viewing application that is designed for viewing images in a clean and intuitive working environment. It share many similarities with Windows Photo Viewer that shipped with Windows 7 and Windows Vista. ImageGlass provides tools that can be used to conver images to different formats, invluding BMP, EMF, EXIF, GIF, ICO, JPG, PNG, TIFF, WMV and BaseString.
Pixelfed
A free and ethical photo sharing platform, powered by ActivityPub federation protocol. Pixelfed is open-sourced software licensed under the AGPL license.
PhotoFlare
PhotoFlare is a powerful, free an open-spource cross-platform image editor. With PhotoFlare you can enjoy a simple, yet powerful image editor that gets straight to the point when it comes to improve and modify images. Some of the features of PhotoFlare include basic image editing capabilities, paint brushes, image filters, colour adjustments and more advanced features such as batch image processing. PhotoFlare is written in C++ and utilize the Qt framework for its interface. The software is openly developed by the community and is released under the GPL-3.0 License.
Aseprite
Aseprite is a pixel art software for macOS, Linux and Windows with which you can create animated sprites and graphics. Aseprite is much used tool in the pixel art and indie game development scene where the tool allow designers to gets down to the nitty-gritty and create amazing pixel sprites and animations.
Fotor
Fotor is a free web-based photo editor and graphic design software that allows you to work in your browser. The software provides common photo editing tools such as filters, frames, text, stickers and effects. Fotor is used by over 300 milion users, for browser-based design and photo editing tasks.
Pinta
Pinta is a free and open source drawing and image editing software similar paint.net. Pinta provides a simple yet powerful user interface that enables it users to draw and manipulate images on Linux, Mac, Windows, and BSD.
Inkscape
A free and open-source vector graphics editor developed by macOS, Linux and Windows. Inkscape provides a rich set of features and is widely used for both artistic and technical illustrations such as cartoons, clip art, logos, typography, diagramming and flowcharting. With Inkscape you can work on Scalable Vector Graphics (SVG) with a modern and intuitive UI and UX loved by many in the open-source community.
Apache NetBeans
Apache NetBeans is free and open-source IDE that combines development environment, a tooling platform and application framework into one package. With Apache NetBeans developer can build applications with Java, JavaScript, PHP, HTML5, CSS, and other languages. Apache NetBeans also features code highlighting, both syntactically and semantically, while also letting developers refactor code with a wide range of powerful and handy tools. The software is openly developed by the Apache Foundation and is available for macOS, Linux, Windows and BSD.
Darktable
Darktable is a free and open-soource photo editing software created for photographers, by photographers. Darktable is specifically designed for non-destructive raw photo post-production editing. The Darktable development community is comprised of avid photographers that has a good understanding of real world problems, challenges, and workflows.