Patent ID: 8639501

Claim:
A method of enhancing spatial audio signals, comprising: receiving an Algebraic Code Excited Linear Prediction (ACELP) coded audio signal comprising a plurality of blocks; for each received block, estimating a signal type based on at least one of the received signal and a set of decoder parameters, wherein estimating the signal type comprises: determining if the signal block comprises a strong and narrow band-pass component of a human pitch with a center frequency in the range of 100-500 Hz; and estimating a center frequency as a lowest pitch frequency of the signal block if it is determined that the signal block includes the narrow band-pass component; estimating a pitch frequency based on at least one of the received signal and the set of decoder parameters; determining filtering parameters based on at least one of the estimated signal type and the estimated pitch frequency, wherein the filtering parameters include a cut-off off frequency, wherein the cut-off frequency is set below the lowest pitch frequency if it is determined that the signal block includes the narrow band-pass component and wherein the cut-off frequency is decreased towards 50 Hz if it is determined that the narrow signal block does not include the narrow band-pass component; and high pass filtering the received signal based on the determined filter parameters to provide a high pass filtered output signal.