Comparison of voice activity detection algorithms for VoIP

We discuss techniques for Voice Activity Detection (VAD) for Voice over Internet Protocol (VoIP). VAD aids in saving bandwidth requirement of a voice session thereby increasing the bandwidth efficiently. In this paper, we compare the quality of speech, level of compression and computational complexity for three time-domain and three frequency-domain VAD algorithms. Implementation of time-domain algorithms is computationally simple. However, better speech quality is obtained with the frequency-domain algorithms. A comparison of merits and demerits along with the subjective quality of speech after removal of silence periods is presented for all the algorithms. A quantitative measurement of speech quality for different algorithms is also