PERCEPTUAL WEIGHTING DEVICE AND METHOD FOR EFFICIENT CODING OF WIDEBAND SIGNALS

摘要

A perceptual weighting device for producing a perceptually weighted signal i n response to a wideband signal comprises a signal preemphasis filter, a synthesis filter claculator, and a perceptual weightin g filter. The signal preemphasis filter enhances high frequency content of the wideband signal to thereby produce a preemphasised signal. Th e signal preemphasis filter has a transfer function of the form: p(z)-1 - .mu.z-1 wherein .mu. is a preemphasis factor having a value located between 0 and 1. The synthesis filter calculator is responsive to the preemphasised signal for producing synthesis filter coefficients. Finally, t he perceptual weighting filter processes the preemphasised signal in relation to the synthesis filter coefficients to produce the perceptually weighted signal. The perceptual weighting filter has a transfer function, with fixed denominator, of the form: W(z) A (z/.gamma.1) / (1- .gamma.2z-1) where 0 < .gamma.2 < .gamma.1 .ltoreq. and .gamma.1 and . gamma.2 are weighting control values, whereby weighting of the wideband signal in a format region is substantially decoupled from a spectral tilt of this wideband signal.