IMPROVED HARMONIC TRANSFORMATION BASED ON BLOCK OF THE SUB-BAND Russian patent published in 2018 - IPC G10L21/02 

FIELD: data processing.

SUBSTANCE: invention relates to coding systems for a source audio signal that use a harmonic transformation method for high-frequency reconstruction (HFR). System and method configured to generate a time-stretched and /or frequency-converted signal from an input signal is described. System includes an analysis filter unit configured to generate the signal of the analyzed sub-band from a received signal; where the signal of the analyzed sub-band includes a number of complex-valued analyzed discrete values, each has a phase and an amplitude. System includes a sub-band processing module configured to determine a synthesized sub-band signal from an analyte sub-band signal. Sub-band processing module performs non-linear processing on a block basis, where the amplitude of the discrete values of the signal of the synthesized sub-band is determined from the amplitude of the corresponding discrete values of the signal of the analyzed sub-band and the previously determined discrete value of the signal of the analyzed sub-band.

EFFECT: technical result is to reduce the computational complexity of the encoding process with increasing the quality of the audio signal for different types of audio signal.

15 cl, 7 dwg