The AC-3 format was released as the Dolby Digital standard in 1991. Bradley at the University of Surrey in 1987.ĭolby Laboratories adapted the MDCT algorithm along with perceptual coding principles to develop the AC-3 audio format for cinema needs.
The DCT was adapted into the modified discrete cosine transform (MDCT) by J.P. It is a modification of the discrete cosine transform (DCT) algorithm, which was first proposed by Nasir Ahmed in 1972 and was originally intended for image compression. The main basis of the Dolby AC-3 multi-channel audio coding standard is the modified discrete cosine transform (MDCT), a lossy audio compression algorithm.
The first use of Dolby Digital was to provide digital sound in cinemas from 35mm film prints today, it is now also used for applications such as TV broadcast, radio broadcast via satellite, digital video streaming, DVDs, Blu-ray Discs and game consoles. Originally named Dolby Stereo Digital until May 1995, the audio compression is lossy, based on the modified discrete cosine transform (MDCT) algorithm. Dolby Digital, originally synonymous with Dolby AC-3, is the name for what has now become a family of audio compression technologies developed by Dolby Laboratories.
