glfer is a GTK+ application that shows the input signal frequency spectrum in a waterfall display and can also control a transmitter to emit slow-CW (QRSS) signals. The signal to be analyzed can be acquired in real-time from the sound card or can be read from a WAV file. The signal spectrum can be computed using four different spectral estimators. The spectrogram display can be saved as an image; you can choose to save the entire window, or select a rectangular region to save with the mouse.
bbJewel creates a PDF of a cover for the listed MP3 files for the purpose of printing a jewel case insert. It parses each file and extract the title, artist, and length of the recording. It also scans the files for included cover images. You can provide the CD title and the cover image to use on the command line.
ll-plugins is a small collection of LV2 plugins and a host that runs them. All plugins are installed in separate LV2 bundles (except the ones that are closely related, like the math-constant plugins or the mono and stereo versions of the peak meter). The GUIs, for the plugins that have GUIs, are installed in bundles of their own to make it easier for packagers to put them in separate binary packages to avoid Gtk dependencies for the plugins themselves. There are synths, event processors, simple audio and control manipulators and GUI-based plugins.
DTMF2NUM is a tool for decoding DTMF and MF tones from PCM wave files. It supports any type of wave file, automatic optimizations (DC bias adjust and normalization), and both WAV and raw PCM data. The program has been successfully tested with many audio files, including ones that are highly dirty and damaged (for example, recorded with a microphone in a room or at very low volumes or with some noise).
Twibright Pitchotron analyzes any MP3 into the semitones that are being played, displayed in a scrolling coloured graph on a video. It aids musical transcription. It includes coloured piano key stickers that enable accompanying arbitrary music and improvising even to musical analphabets.
The Epeios MIDI to XML converter makes it possible to convert binary MIDI files to a format that allows them to be handled effectively with tools like CVS. If you put, using your favorite MIDI sequencer, the CVS '$Id$' tag (or other CVS tags) in the comment tag of the MIDI file, the changes made to this tag by CVS are propagated into the MIDI file.