Patent ID: 8403105
Filing Date: 2013-03-26
Classification: G01S,G10L,H04N,H04S

Abstract:
1. A method of estimating a sound source location for a sound source by particle filtering, the method comprising: iterating the step of generating a set of particles for a time instant, the set of particles representing a probability density function for a state variable comprising the sound source location at the time instant; the step comprising for each particle of the set of particles: generating a state value for the particle at the time instant in response to a state value of the particle at a previous time instant, and generating a weight for the particle at the time instant in response to (i) a weight of the particle at the previous time instant and (ii) a measurement at the time instant reflecting the sound source location; and generating a state variable estimate comprising a sound source location estimate for a first time instant in response to a combination of state values for the set of particles at the first time instant, the contribution from each particle of the set of particles depending on the weight of the particle, wherein generating the weight for the particle at the time instant comprises determining the weight in response to a correlation between estimated acoustic transfer functions that represent relative variations in acoustic paths from the sound source to at least two sound recording positions for the first time instant, wherein the correlation is determined via a correlation function that includes how well the acoustic transfer functions match for a given relative delay offset, further wherein a correlation value for a given delay is perceived as an indication of a likelihood that a path difference between paths from the at least two sound recording positions to the sound source corresponds to that relative delay offset.