METHOD AND APPARATUS FOR ENCODING AND DECODING AUDIO SIGNAL USING HIERARCHICAL SINUSOIDAL PULSE CODING

摘要

The present invention relates to a method and an apparatus for encoding and decoding an audio signal. The method for encoding an audio signal according to one embodiment of the present invention comprises: receiving a converted audio signal; dividing the converted audio signal into a plurality of sub-bands; performing a 1st sinusoidal pulse coding on the plurality of sub-bands; determining a block where a 2nd sinusoidal pulse coding is to be performed, out of the plurality sub-bands; and performing the 2nd sinusoidal pulse coding on the corresponding block, wherein a 1st sinusoidal pulse coding step is variably performed depending on the pulse coding information. According to the present invention, when encoding or decoding an audio signal in an upper layer using the hierarchical sinusoidal pulse coding, the sinusoidal pulse coding of a lower layer is also taken into consideration for more improvements in the quality of a synthesized signal.