Patent ID: 8639519

Claim:
A method for coding an input audio signal, the method comprising: encoding the input signal using a core layer encoder to produce a core layer encoded signal; decoding the core layer encoded signal to produce a reconstructed signal; comparing the reconstructed signal to the input signal, wherein the comparing comprises estimating an energy E_err of the reconstructed signal that contain errors, determining a ratio S(k)/Sc(k) of component S(k) of the input signal to the component Sc(k) of the reconstructed signal exceeds a threshold value and summing the energies of those components Sc(k) of the reconstructed signal when the ratio S(k)/Sc(k) does not exceed the threshold value; selecting an enhancement layer encoder from a plurality of enhancement layer encoders dependent upon the comparison between the reconstructed signal and the input signal; and generating an enhancement layer encoded signal using the selected enhancement layer encoder, the enhancement layer encoded signal being dependent upon the input signal.