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 weighting filter. The signal preemphasis filter enhances high frequency content of the wideband signal to thereby produce a preemphasised signal. The signal preemphasis filter has a transfer function of the form: P(z)=1 - .mu.z-1 wherein .mu. is a preemphasi s factor having a value located between 0 and 1. The synthesis filter calculat or is responsive to the preemphasised signal for producing synthesis filter coefficients. Finally, the perceptual weighting filter processes the preemphasised signal in relation to the synthesis filter coefficients to produce the perceptually weighted signal. The perceptual weighting filter ha s 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 1 and .gamma.2 and .gamma.1 are weighting control values, whereby weighting of the wideband signal in a form at region is substantially decoupled from a spectral tilt of this wideband sign al.