FIELD: information technology.
SUBSTANCE: apparatus includes: an offset determiner for determining an offset frequency for each iteration start frequency of a plurality of iteration start frequencies based on the spectrum of the audio signal, characterised by that the number of discrete sample values of the spectrum is larger than a number of iteration start frequencies; a frequency determiner which determines a new plurality of iteration start frequencies by increasing or reducing each iteration start frequency of the plurality of iteration start frequencies by the corresponding determined offset frequency; and an iteration controller which provides the new plurality of iteration start frequencies to the offset determiner for a further iteration or forms a plurality of local centre of gravity frequencies, if a predefined iteration termination condition is fulfilled, wherein the plurality of local centre of gravity frequencies is equal to the new plurality of iteration start frequencies.
EFFECT: improved method of determining plurality of local centre of gravity frequencies of the spectrum of an audio signal in order to reduce computational complexity thereof.
22 cl, 22 dwg
