METHODS AND SYSTEMS FOR EFFICIENT RECOVERY OF HIGH FREQUENCY AUDIO CONTENT Russian patent published in 2016 - IPC G10L21/388 G10L19/02 

FIELD: information technology.

SUBSTANCE: invention relates to encoding, decoding and processing an audio signal, in particular, it relates to means of recovering high-frequency content of an audio signal from low-frequency content of same audio signal. Method comprises determining a first banded tonality value for a first frequency subband. First banded tonality value is used for approximating a high frequency component of audio signal based on a low frequency component of audio signal. Determining a set of transform coefficients in a corresponding set of frequency bins based on a block of samples of audio signal. Determining a set of bin tonality values for set of frequency bins using set of transform coefficients, respectively. Forming a first subset of two or more of set of bin tonality values for two or more corresponding adjacent frequency bins of set of frequency bins lying within first frequency subband, thereby yielding first banded tonality value for first frequency subband.

EFFECT: technical result is reducing complexity of calculations in audio encoding based on systems with spectral expansion.

29 cl, 15 dwg, 2 tbl