Patent ID: 6094636
Filing Date: 2000-07-25
Classification: G10L,H04B,H04N

Abstract:
A scalable audio coding method for coding audio signals into a layered datastream having a base layer and a predetermined number of enhancement layers, comprising the steps of:(a) signal-processing input audio signals and quantizing the same for each predetermined coding band;(b) coding the quantized data corresponding to the base layer within a predetermined layer size;(c) coding the quantized data corresponding to the next enhancement layer of the coded base layer and the remaining quantized data uncoded and belonging to the coded layer, within a predetermined layer size; and(d) sequentially performing the layer coding steps for all layers, wherein the steps (b), (c) and (d) each comprise the steps of:(i) obtaining gamut bit allocation information representing the number of bits of the quantized data corresponding to the respective subbands belonging to a layer to be coded;(ii) obtaining the number of bits allocated to the respective subbands within each subband size of the layers;(iii) generating an index representing the presence of quantized data for predetermined frequency components forming the subbands for the quantized data corresponding to the number of allocated bits; and(iv) generating bitstreams by coding the quantized data corresponding to the gamut bit allocation information, quantization step size, index and number of bits allocated to the respective subbands, by a predetermined coding method.