Method and device for decoding an audio soundfield representation for audio playback

摘要

Abstract Soundfield signals such as e.g. Ambisonics carry a representation of a desired sound field. The Ambisonics format is based on spherical harmonic decomposition of the soundfield, and Higher Order Ambisonics (HOA) uses spherical harmonics of at least 2 nd order. However, commonly used loudspeaker setups are irregular and lead to problems in decoder design. A method for improved decoding an audio soundfield representation for audio playback comprises calculating (110) a panning function (W) using a geometrical method based on the positions of a plurality of loudspeakers and a plurality of source directions, calculating (120) a mode matrix (E) from the loudspeaker positions, calculating (130) a pseudo-inverse mode matrix (E*) and decoding (140) the audio soundfield representation. The decoding is based on a decode matrix (D) that is obtained from the panning function (W) and the pseudo-inverse mode matrix (E*). Fig.1 WO 2011/117399 PCT/EP2011/054644 120 *130 135 get order SF, 140 AUdec Fig.1 *9 x' Fg p ' Kl Fig.2