Patent ID: 6728222
Filing Date: 2004-04-27
Classification: H04L,H04M

Abstract:
A conference terminal control device provided with conference terminals installed in a plurality of locations, a decoder for decoding compressed voice codes from said conference terminals, an attenuation circuit for adjusting decoded voice levels outputted by said decoder, a synthesizing circuit for adding/synthesizing output voice signals of said attenuation circuit, an encoder for compressing a voice signal outputted by said synthesizing circuit, and a distribution circuit for distributing compressed voice codes to said conference terminals so that the conference terminals are interconnected, the conference terminal control device comprising:demultiplexers for separating voice information from said conference terminals into the compressed voice code and a voiced/unvoiced code; a speaker detection circuit for detecting whether the compressed voice code is voiced or unvoiced based on said voiced/unvoiced code and measuring the number of voiced conference terminals; a first selector for supplying the compressed voice codes from said detected voiced conference terminals to said decoder when the measured number of voiced conference terminals from said speaker detection circuit is larger than a predetermined number, and for supplying the compressed voice codes from the detected voiced conference terminals to a second selector when said measured number is equal to or less than the predetermined number; and the second selector for selecting said encoder when the measure number is larger than the predetermined number, for selecting said first selector when said measured number is equal to or less than the predetermined number, and for outputting the compressed voice code from either the selected encoder or first selector to said distribution circuit.