COMPANDING APPARATUS AND METHOD TO REDUCE QUANTIZATION NOISE USING ADVANCED SPECTRAL EXTENSION

摘要

Embodiments relate to a compression method and system for reducing coding noise in an audio codec. The compression process divides the initial audio signal into a plurality of segments using a defined window shape, calculates a broadband gain in the frequency domain using a non-energy based average of the frequency domain samples of the initial audio signal, and calculates a relatively low It amplifies the intensity segments and reduces the original dynamic range of the initial audio signal through a compression process that applies individual gain values to attenuate the relatively high intensity segments. The compressed audio signal then amplifies the relatively high intensity segments and extends back to the substantially original dynamic range applying inverse gain values to attenuate the relatively low intensity segments. The QMF filterbank is used to analyze the initial audio signal to obtain a frequency domain representation.