FIELD: physics.
SUBSTANCE: present invention provides efficient implementation of high-frequency reconstruction (HFR), amplified by cross products, where new component with frequency QΩ+rΩ0 is generated based on existing components with frequencies Ω and Ω+Ω0. Invention provides for harmonic conversion based on a subband block, where a time block of complex-valued discrete subband values is processed by a well-known phase modification. Superposition of several modified discrete values gives the resultant effect of limiting undesirable combination components, thereby making it possible to use a coarser frequency resolution and/or a lower degree of resampling. In one embodiment, the invention further comprises a window function suitable for use with a cross-product-amplified subband block-based HFR. Hardware version of the invention may include analysis filter unit (101), subband processing module (102) configured by control data (104) and synthesis filter unit (103).
EFFECT: more efficient implementation of HFR, particularly a method which reproduces an audio signal with high accuracy while reducing computational costs.
3 cl, 9 dwg
