Patent ID: 6108625
Filing Date: 2000-08-22
Classification: G10L,H04B,H04N

Abstract:
A computer usable medium having computer readable program code means embodied therein for coding audio signals into a layered datastream having a base layer and a predetermined number of enhancement layers, the computer readable program code means in said computer usable medium comprising:(a) computer readable program code means for causing a computer to effect signal-processing of input audio signals and quantizing the same for each predetermined coding band;(b) computer readable program code means for causing a computer to effect coding of the quantized data corresponding to the base layer within a predetermined layer size;(c) computer readable program code means for causing a computer to effect coding of the quantized data corresponding to the next enhancement layer of the coded base layer and the remaining quantized data uncoded and belonging to the enhancement layer, within a predetermined layer size; and(d) computer readable program code means for causing a computer to effect sequentially performance of the layer coding steps for all layers, wherein the computer readable program code means (b), (c) and (d) each comprise:(i) computer readable program code means for causing a computer to effect 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) computer readable program code means for causing a computer to effect obtaining the number of bits allocated to the respective subbands within each subband size of the layers;(iii) computer readable program code means for causing a computer to effect 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) computer readable program code means for causing a computer to effect 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.