Patent ID: 6950794

Claim:
A method of determining scalefactors used to encode a signal, comprising the steps of: associating a plurality of distortion thresholds, respectively, with a plurality of frequency scalefactor bands of the signal; transforming the signal to yield a plurality of sets of transform coefficients, one set for each of the frequency scalefactor bands; and calculating a plurality of total scaling values, one for each of the frequency scalefactor bands, such that an anticipated distortion based on the product of a transform coefficient for a given scalefactor band with its respective total scaling value is less than a corresponding one of the distortion thresholds; and wherein a given total scaling value A sfb for a particular frequency scalefactor band is calculated according to the equation: A sfb =2[4/(9 BW sfb )] 2/3 *(1 /M sfb ) 2/3 *(Σ x i ) 1/3 , where BW sfb is the bandwidth of the particular frequency scalefactor band, M sfb is the corresponding distortion threshold, and Σx j is the sum of all of the transform coefficients for the particular scalefactor band.