9. The non-transitory computer-readable storage medium in claim 8 , wherein the posterior distribution voice activity is estimated from an entire past history in real-time of a speech state given a latency.
10. The non-transitory computer-readable storage medium of claim 9 , further comprising: receiving the posterior distribution of voice activity; applying a criterion for selecting an optimal sequence based on the posterior distribution of voice activity; and generating a Voice Activity Detection (VAD) output that indicates whether the acoustic signal includes speech.