Patent ID: 9530435
Filing Date: 2016-12-27
CPC Classification: G10L

Claim Text:
1. A voiced sound interval classification device for determining whether voice signals collected by a plurality of microphones are in a voice sound interval or a voiceless sound interval, comprising: at least one memory operable to store program instructions; at least one processor operable to read the stored program instructions; and according to the stored program instructions, the at least one processor is configured to be operated as: a vector calculation unit which calculates, from a power spectrum time series of said voice signals collected by said plurality of microphones, a multidimensional vector series as a vector series of a power spectrum having as many dimensions as the number of said plurality of microphones; a difference calculation unit which calculates, with respect to each time of said multidimensional vector series sectioned by an arbitrary time length, a vector of a difference between the time in question and the preceding time; a sound source direction estimation unit which estimates, as a sound source direction, a main component of a plurality of main components of said differential vector obtained while allowing the plurality of main components of said differential vector to be non-orthogonal and exceed a space dimension; and a voiced sound interval determination unit which determines whether each sound source direction obtained by said sound source direction estimation unit is in a voiced sound interval or a voiceless sound interval by using a predetermined voiced sound index indicative of a likelihood of a voiced sound interval of said voice signal applied at each time; wherein said sound source direction estimation unit further calculates said sound source direction as a vector, and calculates certainty of said sound source direction estimated by the norm of the sound source direction vector, and said voiced sound interval determination unit further calculates a sum of said voiced sound indexes of the respective times with respect to said sound source direction, and calculates a multiplication value of the sum of said voiced sound indexes of the respective times with respect to said sound source direction and the norm of the sound source direction vector estimated in the voiced sound index, and compares the multiplication value with a predetermined threshold value to determine whether said sound source direction is in a voiced sound interval or a voiceless sound interval.