darktable

darktable is an open source photography workflow application and raw developer. A virtual lighttable and darkroom for photographers. It manages your digital negatives in a database, lets you view them...
Language(s): C, GTK+
Operating system(s): FreeBSD, Linux, Mac OS, Solaris, Windows
License: GNU General Public License 3 or later.

digiKam

digiKam is an advanced open-source digital photo management application that runs on Linux, Windows, and MacOS. The application provides a comprehensive set of tools for importing, managing, editing, ...
Language(s): C++, QT
Operating system(s): Linux, Windows, Mac OS
License: GNU General Public License

eSpeakNG

The eSpeak NG (Next Generation) Text-to-Speech program is an open source speech synthesizer that supports 102 languages and accents, based on the eSpeak engine created by Jonathan Duddington. It suppo...
Language(s): C
Operating system(s): Linux, Windows, Mac OS X, FreeBSD
License: GNU GPL v3+

gThumb

gThumb is an image viewer and browser for the GNOME Desktop. It also includes an importer tool for transferring photos from cameras. gThumb is available for most Linux distributions, just do a sear...
Language(s): C (GTK+)
Operating system(s): Unix, Linux
License: GNU General Public License

gnuplot

Gnuplot is a portable command-line driven graphing utility for Linux, OS/2, MS Windows, OSX, VMS, and many other platforms. The source code is copyrighted but freely distributed (i.e., you don't have ...
Language(s): C
Operating system(s): Linux, OS/2, MS Windows, OSX, VMS and more.
License: Gnuplot license