IMPROVED SUBBAND BLOCK BASED HARMONIC TRANSPOSITION Russian patent published in 2014 - IPC G10L21/02 

FIELD: physics, acoustics.

SUBSTANCE: invention relates to means of encoding a source audio signal to form an equalised multichannel audio signal. A harmonic transposition method for high frequency reconstruction is employed. A signal of the analysed subband is generated from an input signal, where the signal of the analysed subband includes a series of complex-valued analysed discrete values, each having a phase and an amplitude. A signal of the synthesised subband is determined from the signal of the analysed subband using a subband transposition factor and a subband stretch factor. Block-based nonlinear processing is performed, where the amplitude of the discrete values of the signal of the synthesised subband is determined from the amplitude of corresponding discrete values of the signal of the analysed subband and a pre-determined discrete value of the signal of the analysed subband. A time-stretched and/or frequency-transposed signal is generated from the signal of the synthesised subband.

EFFECT: reduced computational complexity of the encoding process with high quality of the audio signal.

38 cl, 7 dwg