US 10,872,612 B2 · Method and apparatus for determining for the compression of an HOA data frame representation a lowest integer number of bits required for representing non-differential gain values

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 of 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, wherein the bitstream includes a number of HOA coefficients corresponding to 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(N,Ω1(N), . . . ,ΩO(N)),
N is the order, NMAX is a maximum order of interest, Ω1(N), . . . , ΩO(N) are directions of said virtual loudspeakers, O=(N+1) is the number of HOA coefficient sequences, and K is a ratio between the squared Euclidean norm ∥Ψ∥22 of said mode matrix and O,
wherein √{square root over (KMAX)}=1.5.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application

16/255,358Filed 23 Jan 2019 · division

Priority

EP 1430602327 Jun 2014

Published

US 2019/0214027 A111 Jul 2019

Granted

22 Dec 2020

Term ends

Not estimatedThe source records don’t support an estimate.

Classification6 codes

G10L 19/008
Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals,…:…
H04S 7/30
Indicating arrangements; Control arrangements, e.g. balance control: control circuits for electronic adaptation of the sound field
H04S 2400/11
Details of stereophonic systems covered by H04S but not provided for in its groups: positioning of individual sound objects, e.g. moving airplane,…
H04S 2420/11
Techniques used stereophonic systems covered by H04S but not provided for in its groups: application of ambisonics in stereophonic audio systems

Family

PCT/EP2015/063912Parent of this division · filed 22 Jun 2015

US 2019/0214027 A1Pre-grant publication · published 11 Jul 2019

Application15/319,699Parent of this division

US 10,236,003 B2Parent of this division

US 2017/0133020 A1Published application

US 10,872,612 B2This patent

From the US filing history. Foreign family members aren’t listed.

Method and apparatus for determining for the compression of an HOA data frame representation a lowest integer number of bits required for representing non-differential gain values

Life of this patent

Method and apparatus for determining for the compression of an HOA data frame representation a lowest integer number of bits required for representing non-differential gain values

Life of this patent

Abstract

Claims3