Multiview Soundfield Imaging in the Projective Ray Space

Abstract

A soundfield image a data structure that efficiently encodes and represents the wave field captured by a microphone array. Its representation based on the directional plenacoustic function, which defined the radiance of the acoustic paths (rays) that cross the segment that the array lies upon. The soundfield image can be processed as is to develop a variety of applications. In its original formulation, the soundfield image based on a Euclidean parameterization that can accommodate a limited range of rays and suitable for managing a single array only. In this paper, we generalize this methodology to the case of multiple microphone arrays deployed in space. The use of multiple arrays allows us to capture truly global information on the sound field but requires us to rethink the ray space, and adopt a global representation of the acoustic rays based on projective geometry. After introducing the new parameterization, we present two examples of applications: the estimation of the mutual poses of two or more arrays (self-calibration); and the localization of multiple acoustic sources. The effectiveness of these applications proven through simulations well real data experiments.