公开(公告)号：US09961470B2

公开(公告)日：2018-05-01

申请号：US15619935

申请日：2017-06-12

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Johannes Boehm ,  Florian Keiler

IPC: H04S7/00 ,  H04S3/00

CPC classification number: H04S7/30 ,  H04S3/008 ,  H04S2420/11

Abstract: The invention discloses rendering sound field signals, such as Higher-Order Ambisonics (HOA), for arbitrary loudspeaker setups, where the rendering results in highly improved localization properties and is energy preserving. This is obtained by a new type of decode matrix for sound field data, and a new way to obtain the decode matrix. In a method for rendering an audio sound field representation for arbitrary spatial loudspeaker setups, the decode matrix (D) for the rendering to a given arrangement of target loudspeakers is obtained by steps of obtaining a number (L) of target speakers, their positions (L), positions (S) of a spherical modeling grid and a HOA order (N), generating (141) a mix matrix (G) from the positions (S) of the modeling grid and the positions (L) of the speakers, generating (142) a mode matrix ({tilde over (Ψ)})from the positions (S) of the spherical modeling grid and the HOA order, calculating (143) a first decode matrix ({circumflex over (D)}) from the mix matrix (G) and the mode matrix ({tilde over (Ψ)}), and smoothing and scaling (144, 145) the first decode matrix ({circumflex over (D)}) with smoothing and scaling coefficients.

公开(公告)号：US20180077510A1

公开(公告)日：2018-03-15

申请号：US15718471

申请日：2017-09-28

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Florian Keiler ,  Johannes Boehm

IPC: H04S3/02 ,  H04S7/00

CPC classification number: H04S3/02 ,  H04S7/308 ,  H04S2400/11 ,  H04S2420/07 ,  H04S2420/11

Abstract: Sound scenes in 3D can be synthesized or captured as a natural sound field. For decoding, a decode matrix is required that is specific for a given loudspeaker setup and is generated using the known loudspeaker positions. However, some source directions are attenuated for 2D loudspeaker setups like e.g. 5.1 surround. An improved method for decoding an encoded audio signal in soundfield format for L loudspeakers at known positions comprises steps of adding (10) a position of at least one virtual loudspeaker to the positions of the L loudspeakers, generating (11) a 3D decode matrix (D′), wherein the positions ({circumflex over (Ω)}1 . . . {circumflex over (Ω)}L) of the L loudspeakers and the at least one virtual position ({circumflex over (Ω)}′L+1) are used, downmixing (12) the 3D decode matrix (D′), and decoding (14) the encoded audio signal (i14) using the downscaled 3D decode matrix ({tilde over (D)}). As a result, a plurality of decoded loudspeaker signals (q14) is obtained.