General Free Software
Audacity – Audio editor and multi-track recorder for most basic tasks.
Ardour – Production system for audio professionals.
Blender – 3d graphic design and video editor.
Filezilla – File transfer program. Great for exchanging files on web servers.
GIMP – Image editing software for all operating systems.
Inkscape – Vector graphics design for all platforms.
Kdenlive – Video editing, visual effects, transitions, and rendering.
Krita – Graphic design and image editing.
LibreOffice – Word processing, spreadsheets, presentations, vector graphics, databases, and formulas.
MakeHuman – Open source avatar design.
Mixxx – Musical DJ playback supporting live track blending and multiple effects.
projectM – Graphical visualizations responsive to audio playback.
Thunderbird – Email client offering message filtering and junk controls.
VLC – Video and audio player for any operating system.
Text To Speech
Festival – Mature open source speech synthesis system.
CMU Sphinx – Series of established open source voice recognition systems.
Kaldi – Extensible speech recognition toolkit written in C++.
Blather – Earlier speech recognizer that will run set commands with spoken presets.
Lucida – Open web-based framework for interactive text search and image matching.
Robot Operating System – Open framework for creating robotic software using Linux.
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