digital audio definition multimedia, file format
A sequence of discrete samples taken from a continuous sound (audio
) waveform. Tens of thousands of samples are taken each second. Each sample represents the intensity of the sound pressure wave at that instant. Apart from the sampling frequency, the other parameter is the digital encoding of each sample including the number of bits
used. The encoding may be linear, logarithmic or mu-law
Digital audio is typically created by taking 16-bit samples over a spectrum of 44.1 thousand cycles per second (kHz), this means that CD quality sound requires 1.4 million bits of data per second. Digital telephone systems use lower sample rates. Filename extension
: .au (Unix
), .snd (MS-DOS
, MS Windows).
See also Audio IFF
on audio file formats is available. Part 1 (ftp://ftp.cwi.nl/pub/audio/AudioFormats.part1), Part 2 (ftp://ftp.cwi.nl/pub/audio/AudioFormats.part2).