US 6,807,524 B1
Perceptual weighting device and method for efficient coding of wideband signalsGeneral
US 6,807,524 B1
Perceptual weighting device and method for efficient coding of wideband signals
Tech Center:
2600 Communications
Examiner:
Talivaldis Ivars Smits
Art Unit:
2655 Videophones and Telephonic Communications; Audio Signals; Digital Audio Data Processing; Linguistics, Speech Processing and Audio Compression
Inventors:
Bruno Bessette; Redwan Salami; Roch Lefebvre
Assignee:
Priority:
10/27/98
Filed:
10/27/99
Granted:
10/19/04
Expiration:
10/27/19
Abstract
A perceptual weighting device for producing a perceptually weighted signal in response to a wideband signal comprises a signal pre-emphasis filter, a synthesis filter calculator, and a perceptual weighting filter. The signal pre-emphasis filter enhances the high frequency content of the wideband signal to thereby produce a pre-emphasized signal. The signal pre-emphasis filter has a transfer function of the form: P(z)=1−&mgr;z−1, wherein &mgr; is a pre-emphasis factor having a value located between 0 and 1. The synthesis filter calculator is responsive to the pre-emphasized signal for producing synthesis filter coefficients. Finally, the perceptual weighting filter processes the pre-emphasized 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/&ggr;1)/(1−&ggr;2z−1) where 0<&ggr;2<&ggr;1≦1.