METHOD AND APPARATUS FOR ENCODING AUDIO SIGNAL, AND METHOD AND APPARATUS FOR DECODING AUDIO SIGNAL

摘要

A method and an apparatus for encoding an audio signal, and a method and an apparatus for decoding an audio signal are provided to encode an audio signal effectively by mixedly using a time-frequency scheme and a parametric scheme according to each audio band. A band dividing unit(110) divides an input audio signal into a plurality of audio bands. A coding scheme selecting unit(120) selects a coding scheme for each audio band. An audio encoding unit(130) encodes each audio band according to a coding scheme selected for each audio band. A bit stream generating unit(140) generates a bit stream including all the encoded data of each audio band. The coding scheme selecting unit selects one of a parametric coding scheme and a time-frequency coding scheme, in which the size of encoded data is smaller. The parametric coding scheme is an SSC(Sinusoidal Coding) scheme. The time-frequency coding scheme is an AAC(Advanced Audio Coding) scheme.