METHOD AND APPARATUS FOR ENCODING AUDIO SIGNAL, AND METHOD AND APPARATUS FOR DECODING AUDIO SIGNAL

摘要

A method and an apparatus for encoding/decoding an audio signal is provided to increase coding efficiency without affecting sound quality by considering amplitude components of harmonic signals contained in harmonic parameters as signals in a time region when expressing a harmonic envelope, executing time-frequency conversion, and encoding some of converted values. An apparatus(100) for encoding an audio signal comprises a harmonic analyzer(110), a time-frequency converter(120), and a converted value encoder(130). The harmonic analyzer executes a harmonic analysis with regard to an input signal and calculates harmonic parameters with regard to the harmonic signals. The time-frequency converter considers amplitude components of the harmonic signals contained in the harmonic parameters as signals in a time region to execute time-frequency conversion. The converted value encoder encodes the time-frequency converted values.