×

Process for searching for a noise model in noisy audio signals

  • US 6,438,513 B1
  • Filed: 12/30/1999
  • Issued: 08/20/2002
  • Est. Priority Date: 07/04/1997
  • Status: Expired due to Term
First Claim
Patent Images

1. A process for automatically searching for noise models in noisy audio input signals, comprising:

  • digitizing the input signals;

    processing the input signals based on an active noise model;

    chopping the input signals into successive frames of P samples; and

    searching for a new noise model in the input signals, by searching for N successive frames having expected characteristics of a noise, storing the N×

    P corresponding samples so as to construct the new noise model useful in denoising the input signals, and iteratively repeating the search so as to find the new noise model and store the new noise model as a replacement for the active noise model or retain the active noise model according to characteristics of the active noise model and the new noise model, wherein searching for the new noise model comprises, searching for N successive frames whose energies are close to one another, N lying between a minimum value N1 and a maximum value N2, calculating an average energy of the N successive frames, and storing the N×

    P samples in a guise of a new noise active model if a ratio between the average energy of the new noise model and the average energy of the frames of the active noise model previously stored is less than a determined replacement threshold.

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