公开(公告)号：JP2002366174A

公开(公告)日：2002-12-20

申请号：JP2002162041

申请日：2002-06-03

Applicant: TELOGY NETWORKS INC

Inventor： LI DUNLING ,  THOMAS DANIEL C ,  SISLI GOKHAN

IPC: G10L11/00 ,  G10L11/02 ,  G10L21/02 ,  G10L25/93

Abstract: PROBLEM TO BE SOLVED: To solve the divergence problem of background noise characteristics obtained by using a method of a G.729 annex B. SOLUTION: A method of initializing an ITU Recommendation G.729 Annex B voice activity detection(VAD) device is disclosed, having the steps of extracting a set of parameters from a signal that characterize the signal (16); calculating an energy measure of the signal from the set of parameters; comparing the energy measure with a reference value (23); determining an initial value for an average of a noise characteristic of the signal (20); and counting the number of times the energy measure equals or exceeds the reference level (26).

公开(公告)号：JP2002237785A

公开(公告)日：2002-08-23

申请号：JP2001332962

申请日：2001-10-30

Applicant: TELOGY NETWORKS INC

Inventor： LI DUNLING ,  SISLI GOKHAN ,  THOMAS DANIEL

IPC: G10L11/02 ,  G10L19/00 ,  G10L21/02 ,  H04B1/66 ,  H04B3/20 ,  H04B14/04 ,  H04L12/56

Abstract: PROBLEM TO BE SOLVED: To obtain a method for reducing band width quantity in transmission of a digitized voice packet. SOLUTION: The number of packets to be transmitted is reduced by interrupting the transmission by determining a silent period or a period only with noise by weighting a plurality of elements in relation to perception including frequency masking, masking with time, loudness perception based on tone and difference of audibility based on the tone as characteristics of a human and judging whether or not background noise is updated based on these factors and reduction of the band width quantity in the transmission is consequently achieved.