Low delay audio coding and it's applications
Bo Tang · Information technology newsletter · 2009
General perceptual coding can deliver high sound quality even at low bit rates.However,the total delay of the encoder/decoder chain is usually considerably higher than acceptable delay for two-way communication.On the other hand,the algorithmic delay of speech coding schemes is small enough to make them suitable for two-way communication.However,such schemes only provide good quality for speech signals and usually fail when they are used for more complex audio signals like music.This paper discusses the sources of algorithmic delay in a perceptual codec and gives the method of calculating.Finally,the key technology,performance and applications of MPEG-4 AAC-LD are discussed.