Patent ID: 6240383
Filing Date: 2001-05-29
Classification: G10L

Abstract:
A speech coding and decoding method in a speech coding and decoding system that includes a speech coding system for coding a speech signal and transmitting the same and a speech decoding system receiving the coded signal transmitted from the speech coding system for decoding the same to supply speech, the method comprising:in the speech coding system,discriminating between a speech interval and a no-speech interval in an input sound signal,in case of a speech interval in the judgement result,generating a coded speech signal by referring to a code book created based on speech characteristics at the time of a speech sound as for a speech signal to be coded,in case of a no-speech interval in the judgement result,filtering the information other than speech of an input sound signal, through a filter using LPC parameters calculated from the input speech signal,generating a noise signal by referring to the code book for the coded signal filtered, andsupplying the decoded speech signal or the noise signal while switching the decoded speech signal and the noise signal according to the judgement result, wherein,in the speech decoding system,discriminating between a speech interval and a no-speech interval upon receipt of a code signal supplied from a switch control means of the speech coding system,decoding the input coded signal to generate a speech signal, andin case of a speech interval in the judgement result,filtering the generated speech signal, through a filter using LPC parameters calculated from the input coded signal.