Baudline is a time-frequency browser designed for scientific visualization of the spectral domain. Signal analysis is performed by Fourier, correlation, and raster transforms that create colorful spectrograms with vibrant detail. Conduct test and measurement experiments with the built in function generator, or play back audio files with a multitude of effects and filters. The baudline signal analyzer combines fast digital signal processing, versatile high speed displays, and continuous capture tools for hunting down and studying elusive signal characteristics.
eXtace is a visual sound display/analysis program. It requires Esound (esd) for its audio source. It includes various fast fourier transforms of the audio data in realtime. Its displays include a 3D wireframe flying landscape, a 3D textured flying landscape, a 16-256 channel graphic EQ, three types of scopes, a 3D "spike" flying landscape, and two forms of spectragrams. The 3D traces can be picked up, manipulated, and displayed at nearly any angle. eXtace also features a 3D direction control widget for controlling the angle and speed at which the trace runs away and a gradient/colormap editor for changing the colormap to suit your needs. No OpenGL is required.
The Snack sound extension adds commands for sound play/record and sound visualization, e.g. waveforms and spectrograms. It supports in- memory sound objects, file based audio, streaming audio, WAV, AU, AIFF, and MP3 file formats, synchronous and asynchronous playback. The visualization canvas item types update in real-time and can output postscript. New commands and file formats can be added using the Snack C-API.
speechd implements a /dev/speech device using either the Festival or rsynth speech synthesis packages. All plaintext written to this device will be spoken aloud (or optionally output as morse code if you are using the "morse" program as the underlying driver). Certain programs have been modified to make use of this device, including an ircII script called speech.irc, a Slashdot ticker called slashes and a package for TiK. All of these modified packages are available on the homepage.
The Two Dimensional Spatialization of Sound package takes a single monaural sound signal and processes it to create a binaural signal that places the source of the sound at a selectable arbitrary place around the listener. The package makes use of a set of HRTF Measurements of a KEMAR Dummy-Head Model created by Bill Gardner and Keith Martin of the MIT Media Lab. The sound spatialization software is ANSI C, and can be ported to any platform which will support the sound I/O requirements. The package also includes an FFT written in well-structured C.