Audio file formats are formats for storing audio data on a computer system. Generally they are container formats or audio data formats with a defined storage layer, but can be a raw bit stream too. The storage of digital audio involves sampling the audio voltage, which would correspond to a certain level of signal in a channel with a particular resolution in regular intervals, on playback. The data can then be stored uncompressed or compressed. Compression reduces the file size.
The distinguish between a file format and a codec becomes essential here since a codec encodes and decodes the raw audio data and specific audio file format stores the data in a compatible file. Most of the audio file formats are created with one or more encoders or codecs. Generally the audio file formats support only one type of audio data that is created with an audio coder but a multimedia container format may support multiple types of audio and video data.
Audio file formats are classified into three major groups that include:
- Uncompressed audio formats like WAV, AIFF, AU or raw header-less PCM.
- Lossless compressed audio formats like FLAC, Monkey’s Audio, WavPack, Shorten, Tom’s lossless Audio Kompressor, TTA, ATRAC Advanced Lossless, Apple Lossless, MPEG-4 SLS, MPEG-4 ALS, MPEG-4 DST and Windows Media Audio Lossless.
- Lossy compressed formats like MP3, Vorbis, Musepack, AAC, ATRAC and lossy Windows Media Audio.