Audiality is a highly scalable and portable audio engine and synthesizer. MIDI files are used in combination with scripting and modular synthesis, to minimize file sizes and maximize flexibility. Audiality can be used as a music and sound effects player in multimedia productions, or as a realtime MIDI synthesizer.
AudioMove is a handy GUI-based batch audio file converter/copier program. It can convert various audio file formats to WAV or AIFF format (using libsndfile), and do high-quality sample-rate conversion at the same time (using libsamplerate). It is multi-threaded for maximum throughput, can handle thousands of files per batch, and does recursive directory scans.
The CMU Midi Toolkit (CMT) is a collection of software for writing interactive MIDI software in C. It includes a number of handy utilities along with an application "shell" that provides timing, scheduling, and MIDI interfaces that are portable across DOS, Mac, SGI, and Amiga platforms.
Csound is a powerful and yet easy to use musical synthesis package. Csound was constructed in the tradition of so-called music-N languages, among which the best-known is Music V. It consists of an orchestra- and score-driven executable, written in C for portability. Since Csound is a computational language, it is highly flexible and efficient; complexity is gained only at the expense of computation power. Basically, Csound reads some files and creates the result as a sound file on disk or, on faster machines, in real time through a DAC.
CastCluster provides access to additional content on iTunes, Apple TV, iPod, or a random podcast viewer. It currently supports YouTube, Google Video, Revver, local disks, and RSS feeds as sources of content. It uses ffmpeg for video conversion. It also provides some other bookmarklet functionality, like digg and del.icio.us.
DromeAudio is a small audio manipulation and playback library. It features a simple API for loading, generating, processing, and playing audio. Some of its features include loading and saving WAV sounds, loading Ogg Vorbis sounds, audio mixing/playback, and dynamic audio processing effects such as pitch shifting and echo.
Entagged is a Java audio file tagger which uses the freedb online database for the retrieval of the tags. It supports custom file renaming based on the tags (with any directory stucture), as well as custom tagging based on the file names. MP3, Ogg, and FLAC are currently supported.
The Extended Module Player is a command-line mod player for Unix-like systems that plays over 90 mainstream and obscure module formats from Amiga, Atari, Acorn, Apple IIgs, C64, and PC, including Protracker (MOD), Scream Tracker 3 (S3M), Fast Tracker II (XM), and Impulse Tracker (IT) files.
The FAAC project includes the AAC encoder FAAC and decoder FAAD2. It supports several MPEG-4 object types (LC, Main, LTP, HE AAC, PS) and file formats (ADTS AAC, raw AAC, MP4), multichannel and gapless en/decoding as well as MP4 metadata tags. The codecs are compatible with standard-compliant audio applications using one or more of these profiles.