SPEECH RECOGNITION DEVICE

摘要

PURPOSE:To accurately detect a speech section even in environment where an external noise is loud by detecting the distance between the lips of a speaker and a microphone and entering the section wherein the lips move as a next candidate for the speech section. CONSTITUTION:A distance sensor 3 provided to a microphone device 1 detects and outputs variation in the distance between the microphone 2 and the lips of the speaker 21 including the motion of the lips and their peripheral part when the speaker 21 speaks to a distance calculation part 7. The calculation part 6 converts the detection signal into a digital value and outputs it to a voicing section detection part 7. The detection part 7 uses a threshold value which is determined adaptively to regard the section wherein the largest variation in the distance between the microphone 2 and lips is obtained as the voicing section, and outputs it to a time normalization part 8 as the next candidate for a speech section signal outputted from a speech section detection part 5. When the external noise is too loud to detect the speech section through the microphone 2, the voicing section is utilized to find the speech section.