US 2018/0007484 A1 · METHOD FOR DECODING A HIGHER ORDER AMBISONICS (HOA) REPRESENTATION OF A SOUND OR SOUNDFIELD

Abstract

When compressing an HOA data frame representation, a gain control (15, 151) is applied for each channel signal before it is perceptually encoded (16). The gain values are transferred in a differential manner as side information. However, for starting decoding of such streamed compressed HOA data frame representation absolute gain values are required, which should be coded with a minimum number of bits. For determining such lowest integer number (βe) of bits the HOA data frame representation (C(k)) is rendered in spatial domain to virtual loudspeaker signals lying on a unit sphere, followed by normalisation of the HOA data frame representation (C(k)). Then the lowest integer number of bits is set to βe=┌log2(┌log2(√{square root over (KMAX)}·O)┐+1)┐.

Claims3

Dependent claims

A method for decoding a compressed Higher Order Ambisonics (HOA) sound representation of a sound or sound field, the method comprising:

receiving a bit stream containing the compressed HOA representation, and
decoding the compressed HOA representation based on a lowest integer number βe, wherein the lowest integer number βe is determined based on
βe=┌log2(┌log2(√{square root over (KMAX)}·O)┐+1)┐.
wherein KMAX=max1≦N≦NMAXK(Ω1(N), . . . , ΩO(N)), N is an order of the compressed HOA representation, NMAX is a maximum order of interest of the compressed HOA representation, Ω1(N), . . . , ΩO(N) are directions of virtual loudspeakers, O=(N+1)2 is a number of HOA coefficient sequences, and K is a ratio between the squared Euclidean norm ∥Ψ∥22 of a mode matrix and O,
wherein eMAX>0, and
wherein √{square root over (KMAX)}=1.5.

3 more elements

Dependencies are inferred from the claim text.

Method for decoding a higher order ambisonics (hoa) representation of a sound or soundfield

Life of this patent

Method for decoding a higher order ambisonics (hoa) representation of a sound or soundfield

Life of this patent

Abstract

Claims3