The dywapitchtrack library computes the pitch of an audio stream in realtime. The pitch is the main frequency of the waveform (the "note" being played or sung). It is expressed as a float in Hz. dywapitchtrack is based on a custom-tailored algorithm which is of very high quality, very accurate (precision < 0.05 semitones), with very low latency (< 23 ms) and very low error rates. It has been thoroughly tested on the human voice.
CLAM is a multiplatform software framework for research and application development for the Audio and Music domains. It offers a conceptual model for building systems as well as tools for the analysis, synthesis, and transformation of audio signals using high level representation (notes, spectral peaks, etc.). It also provides multiplatform system abstraction and tools for audio and MIDI file handling, device handling, GUI and XML support, and more. It has proper Linux audio architecture integration (Ladspa, Alsa, OSC, Jack, VST, etc.) and rapid graphical prototyping both for the processing core and the user interface (Qt designer integration).
Find Duplicate Music Files detects music files that contain the same music, even if the files are differently named, and are in different formats such as MP3, OGG, WAV, WMA, M4A, and RealAudio and contain different or non-existent meta-information such as ID3 tags. The program operates on whole directories of music files, analyzes them, and outputs the filenames of pairs that seem similar, based on their audio fingerprint or perceptual hash.
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.
Pkviz is a tool for plotting and cycling through and animating a series of network packets captured by tcpdump. What makes it unique is that the packets’ structure is visualized, not any labels and not time itself. Pkviz takes each byte in a packet and plots it out end-to-end, left-to-right, from the first byte to the last. How high the dot gets plotted depends on the value of the byte: bytes with a value of 0 are at the bottom and those which are 255 (0xff) – the maximum value of a byte – get plotted at the top. This might not be interesting for one packet, but that changes when you start looking at thousands of packets. Pkviz can cycle through thousands of packets in the set so you can see what happened on the wire.
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.
The aim of auch (audio-checker) is to visualize music. It takes audio from the microphone and uses it to simulate an elastic and vibrating surface (chladni-tranform) or the reflection of such a surface (makyoh-transform). Many more transforms can be activated by unlocking the interactive shell.
aubio is a library for audio labelling. Features include onset detection, silence detection, beat tracking, and pitch detection. The goal of this project is to provide automatic labelling features to other audio software projects. Functions can be used offline in sound editors and software samplers, or online in audio effects and virtual instruments.