Patent ID: 8666753

Claim:
A method for encoding an audio signal at a communication device, comprising: receiving, at the communication device, a bit rate value; selecting, by a processing system of the communication device, a set of energy thresholds based on the bit rate value, wherein the set of energy thresholds is one of a plurality of sets of energy thresholds, and wherein the energy thresholds of each set of energy thresholds correspond on a one-to-one basis with a set of sub-bands of the audio signal; receiving, at the communication device, the audio signal; determining, by the processing system, the energy of each sub-band of the set of sub-bands; determining, by the processing system, a highest frequency sub-band that has an energy exceeding the corresponding threshold; determining, by the processing system, a selected bandwidth of the audio signal that includes only those frequencies of the audio signal that are in the highest frequency sub-band that has an energy exceeding the corresponding threshold, as well as all lower frequencies of the audio signal that are above a high-pass cut-off frequency; and encoding, by an audio coding function of the communication device, the selected bandwidth.