Image processing system and method for estimating acoustic property of a movable sound source

Abstract

An image processing system for estimating acoustic properties emitted from a movable sound source on a point in the sound field thereof comprises photoelectric sensors 11 and 12 for measuring a velocity and a moving direction of the sound source; a microphone array 13 for detecting an acoustic energy from the sound source on a detection surface at plural points having an interval smaller than one half of the wave length of the acoustic property, the microphone array 13 moved in a direction perpendicular to the detection surface; a multiplexer 14 for multiplexing signals inputted from the photoelectric sensors 11 and 12 and the microphone array 13 through a single output line, wherein the signals represent a value of the acoustic energy, a velocity and a moving direction of the sound source, and a velocity and a moving direction of the microphone array 13, respectively; and a personal computer 15 for setting relative coordinate systems comprising a hologram coordinate system and a detective coordinate system, in which the hologram coordinate system is moved in the velocity and the direction same with those of the sound source, and the relative coordinate system is moved in the velocity and the direction same with those of the microphone array 13, and in which in order to estimate a value of the acoustic property on a point in the sound field, the personal computer 15 carries out Fourier transform of data relating to the microphone array 13 in the detective coordinate system by a time factor.