Exmus

Exmus is a file format used for storing and playing back music files. It is primarily associated with the libmusicbrainz software project, which is a free and open-source framework for accessing and manipulating music metadata.

Exmus files contain compacted versions of WAV files, which are then embedded with metadata like track names, artist information, and album artwork. The format is designed to be space-efficient, making it ideal for storing large music libraries on embedded systems, mobile devices, and other platforms with limited storage capacity.

The exmus format uses a custom proprietary compression algorithm to reduce the size of the WAV files without significantly degrading audio quality. This compression scheme is typically not designed to be decompressable by the average audio player, requiring dedicated software to decompress and play the files.

Despite its proprietary nature, the exmus format has found use within specific niches, such as embedded media players, DVD players, and set-top boxes. It has also seen adoption in certain fields where compacted audio files are necessary, like marine and military applications where storage space is limited.

Critics argue that the closed nature of the exmus format may make it difficult for developers to implement support for it in their software, leading to a potential lack of interoperability between systems. Nonetheless, the format's adaptability to widely disparate systems has garnered support among certain groups, leading to its continued use in specialized areas.