| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a sound source separation technique which provides a method for efficiently estimating an arrival time difference δ and eliminates the need of overall search operation to increase the speed of estimation. <P>SOLUTION: An arrival time difference δ<SB POS="POST">f,k</SB>, a power spectrum σ<SB POS="POST">f</SB><SP POS="POST">2</SP>of noise, a sound source spectrum s<SB POS="POST">f,t,k</SB>, and a sound source existence probability p(k¾θ) are estimated from an observation signal x<SB POS="POST">f,t</SB>=[x<SB POS="POST">f,t,L</SB>,x<SB POS="POST">f,t,R</SB>]<SP POS="POST">T</SP>in a frequency domain. The estimation is performed in accordance with formula where: m<SB POS="POST">f,t,k</SB>is a posterior probability indicative of an expected value of attribution of the observation signal x<SB POS="POST">f,t</SB>to a sound source k; D is an interval between two microphones; c is a speed of an original signal; ϕ<SB POS="POST">f</SB>=sinc(2πfD/c) is true; ξ<SB POS="POST">f,t,k</SB>=[x<SB POS="POST">f,t,R</SB>-ϕ<SB POS="POST">f</SB>(x<SB POS="POST">t,t,L</SB>-s<SB POS="POST">f,t,k</SB>)] is true; ψ<SB POS="POST">sk</SB>and ψ<SB POS="POST">ξk</SB>are phases of spectra s<SB POS="POST">f,t,k</SB>and ξ<SB POS="POST">f,t,k</SB>respectively; and δ<SB POS="POST">f,k</SB>is the arrival time difference. The uncertainty of ±π which the estimated arrival time difference δ<SB POS="POST">f,k</SB>includes is corrected. <P>COPYRIGHT: (C)2013,JPO&INPIT |
