FIELD: computer technology for audio signal processing.
SUBSTANCE: invention is aimed at ensuring the reproduction of an audio signal with high accuracy, subject to a reduction in computational costs. It is achieved through the implementation of high-frequency reconstruction (HFR) enhanced by cross products, where the new component with frequency QΩ+rΩ0 is generated based on existing components with frequencies Ω and Ω+Ω0. The invention provides for a sub-band block-based harmonic transformation, where a time block of complex-valued sub-band samples is processed by a well-known phase modification. The superposition of several modified samples has the net effect of limiting unwanted combinational components, whereby coarser frequency resolution and/or less oversampling is made possible. In one embodiment of the invention, the invention further comprises a windowing function suitable for use with an HFR based subband block enhanced with cross products. The hardware embodiment of the invention may include an analysis filter unit (101), a subband processing module (102) configurable by control data (104), and a synthesis filter unit (103).
EFFECT: ensuring the reproduction of an audio signal with high accuracy, subject to a reduction in computational costs.
3 cl, 9 dwg
