×

Reconstructing an audio signal having a baseband and high frequency components above the baseband

  • US 9,653,085 B2
  • Filed: 12/06/2016
  • Issued: 05/16/2017
  • Est. Priority Date: 03/28/2002
  • Status: Expired due to Term
First Claim
Patent Images

1. An audio decoder for reconstructing an original audio signal having a baseband up to a cutoff frequency and high-frequency components not included in the baseband above the cutoff frequency, the audio decoder comprising:

  • a bitstream deformatter that extracts a representation of the baseband, an estimated spectral envelope, and noise-blending parameters from an audio bitstream, wherein the representation of the baseband is a frequency domain representation that includes baseband spectral components, and wherein the cutoff frequency is capable of being varied dynamically;

    a spectral component regenerator that copies or translates all or at least some of the baseband spectral components to non-overlapping frequency ranges of the high-frequency components not included in the baseband to generate regenerated spectral components;

    a gain adjuster that modifies a spectral envelope of the regenerated spectral components based at least in part on the estimated spectral envelope and the noise-blending parameters to generate gain-adjusted regenerated spectral components, wherein the noise-blending parameters include a noise parameter for each of a plurality of frequency bands above the cutoff frequency; and

    a synthesis filterbank that;

    combines a frequency domain representation of the baseband with the gain-adjusted regenerated spectral components to form a frequency-domain representation of a reconstructed audio signal, andtransforms the frequency-domain representation of the reconstructed audio signal into a time domain,wherein the audio decoder comprises one or more hardware elements.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×