Voice activity detection process and means for implementing said process

Abstract From the Canadian patent

In a transmission system for transmitting voice signals each signal being sampled and coded to derive therefrom blocks of samples and short term power spectrum characteristics or each block, a voice activity detection process is proposed wherein an energy representative information is derived from each block of sample, which energy representative information is compared with a predetermined threshold and said threshold is adjusted accordingly. Then an active/ambiguous decision is taken based on the relative magnitude of the energy information with respect to the adjusted threshold, which ambiguity is then eventually resolved through analysis of the magnitude of variation of the short term …