APPARATUS AND METHOD FOR CALCULATING NUMBER OF SPECTRAL ENVELOPES Russian patent published in 2013 - IPC G10L21/02 

FIELD: information technology.

SUBSTANCE: apparatus for calculating the number of spectral envelopes includes: a quantisation threshold calculator; a detector for detecting violation of the threshold value using the quantisation threshold; a processor for determining a first envelope border between the pair of neighbouring time portions; a processor for determining a second envelope border between a different pair of neighbouring time portions; a number processor for establishing the number of spectral envelopes having the first envelope border and the second envelope border; a switching decision unit formed to provide a decision switching signal; the decision switching signal yields a speech-like audio signal and a common sound-like audio signal, where the detector is capable of lowering the threshold value for speech-like audio signals. The method describes operation of said apparatus.

EFFECT: efficient encoding in the best quality, especially for signals with slow-varying energy, oscillation intensity of which is too to be detected by ordinary short-time interference detectors.

12 cl, 11 dwg