Patent ID: 9711154
Date: 2017-07-18
CPC Classifications: G10L

Claim:
1. A method for spectrum recovery for spectral decoding of an audio signal, comprising the steps of: obtaining an initial set of spectral coefficients representing at least a portion of said audio signal; dividing said spectra coefficients of said initial set of spectral coefficients into a plurality of frequency bands, each of the plurality of frequency bands comprising a plurality of frequencies between an upper frequency of the frequency band and a lower frequency of the frequency band, wherein one or more of said frequency bands comprises a frequency that is less than a first chosen transition frequency and one or more of said frequency bands comprises a frequency that is greater than said first chosen transition frequency; determining the first chosen transition frequency, wherein the first chosen transition frequency was chosen such that: 1) each of said frequency bands that comprises a frequency that is less than said first chosen transition frequency includes at least one quantized coefficient and 2) each of said frequency bands that comprises a frequency that is greater than said first chosen transition frequency does not include any quantized coefficients; noise filling of spectral holes in said initial set of spectral coefficients below said first chosen transition frequency; and bandwidth extending said initial set of spectral coefficients above said first chosen transition frequency.