Patent ID: 7369663

Claim:
A reverberation applying apparatus for applying a reverberation effect to an audio signal for reproduction of a sound in a desired acoustic space, the apparatus comprising: a space information acquisition section that acquires space information indicating a spatial shape of the acoustic space bordered by a boundary surface and an acoustic reflectivity of the boundary surface enclosing the acoustic space; a point information acquisition section that acquires, point information indicating a type, a direction, and a position of a sound generation point set in the acoustic space as a point of generating the sound, and a type, a direction, and a position of a sound reception point set in the acoustic space as a point of receiving the sound, wherein the type of the sound generation point indicates a specific type of musical instrument, and wherein the type of a sound reception point indicates one of a human and a non-human type of sound reception point; an acoustic ray path estimation section that estimates a set of acoustic ray paths of the sound traveling from the sound generation point to the sound reception point through the acoustic space based on the acquired space information and the point information; a directivity information acquisition section that acquires directivity information indicating an acoustic generation directivity characterizing a directivity of the sound generation point in generating the sound, and an acoustic reception directivity characterizing a directivity of the sound reception point in receiving the sound; a weighting section that estimates each acoustic intensity of the sound around the sound reception point for each of the acoustic ray paths through which the sound travels to the sound reception point from the sound generation point, and weights each acoustic intensity based on the acquired directivity information and the acquired point information indicating the direction of the sound generation point and the direction of the sound reception point; an impulse response determination section that determines an impulse response of the acoustic space based on directions of the respective acoustic ray paths toward the sound reception point and the weighed acoustic intensities of the respective acoustic ray paths; and a convolution operation section that performs a convolution operation between the determined impulse response and the audio signal to apply thereto the reverberation effect specific to the acoustic space.