Apparatus and method for reproducing a spatially extended sound source or apparatus and method for generating a bitstream from a spatially extended sound source

Patent metadata

Field	Value
Publication number	US-11937068-B2
Application number	US-202117332265-A
Country	US
Kind code	B2
Filing date	May 27, 2021
Priority date	Dec 19, 2018
Publication date	Mar 19, 2024
Grant date	Mar 19, 2024

Abstract

An apparatus for reproducing a spatially extended sound source having a defined position and geometry in a space includes an interface for receiving a listener position; a projector for calculating a projection of a two-dimensional or three-dimensional hull associated with the spatially extended sound source onto a projection plane using the listener position, information on the geometry of the spatially extended sound source, and information on the position of the spatially extended sound source; a sound position calculator for calculating positions of at least two sound sources for the spatially extended sound source using the projection plane; and a renderer for rendering the at least two sound sources at the positions to obtain a reproduction of the spatially extended sound source having two or more output signals, wherein the renderer is configured to use different sound signals for the different positions.

First claim

The invention claimed is:

1. An apparatus for reproducing a spatially extended sound source comprising a defined position and geometry in a space, the apparatus comprising:
an interface for receiving a listener position;
a projector for calculating a projection of a two-dimensional or three-dimensional hull associated with the spatially extended sound source onto a projection plane using the listener position, information on the geometry of the spatially extended sound source, and information on the position of the spatially extended sound source;
a sound position calculator for calculating positions of at least two sound sources for the spatially extended sound source using the projection plane; and
a renderer for rendering the at least two sound sources at the positions to acquire a reproduction of the spatially extended sound source comprising two or more output signals, wherein the renderer is configured to use different sound signals for the different positions, wherein the different sound signals are associated with the spatially extended sound source.

2. The apparatus of claim 1 ,
wherein the detector configured to detect a momentary listener position in the space using a tracking system, or wherein the interface is configured for using position data input via the interface.

3. The apparatus of claim 1 , configured for receiving a scene description, the scene description comprising the information on the defined position and the information on the defined geometry of the spatially extended sound source, and at least one sound signal associated with the spatially extended sound source,
wherein the apparatus further comprises a scene description parser for parsing the scene description to retrieve the information on the defined position, the information on the defined geometry and the at least one sound source signal, or
wherein the scene description comprises, for the spatially extended sound source, at least two basis sound signals and location information for each basis sound signal with respect to the information on the geometry of the spatially extended sound source, and wherein the sound position calculator is configured to use the location information for the at least two basis signals when calculating the positions of the at least two sound sources using the projection plane.

4. The apparatus of claim 1 ,
wherein the projector is configured to compute the hull of the spatially extended sound source using the information on the geometry of the spatially extended sound source and to project the hull in a direction towards the listener using the listener position to acquire the projection of the two-dimensional or three-dimensional hull onto the projection plane, or
wherein the projector is configured to project a geometry of the spatially extended sound source as defined by the information on the geometry of the spatially extended sound source in a direction towards to the listener position and to calculate the hull of a projected geometry to acquire the projection of the two-dimensional or three-dimensional hull onto the projection plane.

5. The apparatus of claim 1 ,
wherein the sound position calculator is configured to calculate the sound source positions in the space from hull projection data and the listener position.

6. The apparatus of claim 1 ,
wherein the sound position calculator is configured to calculate the position so that the at least two sound sources are peripheral sound sources and are located on the projection plane, or
wherein the sound position calculator is configured for calculating such that a position of a peripheral sound source of the peripheral sound sources is located on the right of the projection plane with respect to the listener and/or to the left of the projection plane with respect to the listener, and/or on top of the projection plane with respect to the listener and/or at the bottom of the projection plane with respect to the listener.

7. The apparatus of claim 1 ,
wherein the renderer is configured to render the at least two sound sources using
panning operations depending on the positions of the sound sources to acquire loudspeaker signals for a predefined loudspeaker setup, or
binaural rendering operations using head related transfer functions depending on the positions of the sources to acquire headphone signals.

8. The apparatus of claim 1 ,
wherein a first number of related source signals is associated with the spatially extended sound source, the first number being one or greater than one, wherein the related source signals are related to the same spatially extended sound source,
wherein the sound position calculator determines a second number of sound sources used for the rendering of the spatially extended sound source, the second number being greater than one, and
wherein the renderer comprises one or more decorrelators for generating a decorrelated signal from one or more source signals of the first number, when the second number is greater than the first number.

9. The apparatus of claim 1 ,
wherein the interface is configured to receive a time-varying position of the listener in the space,
wherein the projector is configured to calculate a time-varying projection in the space,
wherein the sound position calculator is configured to calculate a time-varying number or sound sources or time-varying positions of the sound sources in the space, and
wherein the renderer is configured to render the time varying number of sound sources or the at least two sound sources at the time varying positions in the space.

10. The apparatus of claim 1 ,
wherein the interface is configured to receive the listener position in six degrees of freedom, and
wherein the projector is configured to calculate the projection depending on the six degrees of freedom.

11. The apparatus of claim 1 , wherein the projector is configured
to calculate the projection as a picture plane such as a plane perpendicular to a sight line of the listener, or
to calculate the projection as a spherical surface around a head of the listener, or
to calculate the projection as a projection plane being located at a predetermined distance from a center of the listener's head, or
to calculate the projection of a convex hull of a spatially extended sound source from an azimuth angle and an elevation angle being derived from spherical coordinates relative to the perspective of a listener's head.

12. The apparatus of claim 1 ,
wherein the sound position calculator is configured to calculate the positions so that the positions are uniformly distributed around the projection of the hull, or so that the positions are placed at extremal or peripheral points of the hull projection, or so that the positions are located at horizontal or vertical extremal or peripheral points of the projection of the hull.

13. The apparatus of claim 1 ,
wherein the sound position calculator is configured to determine, in addition to positions for peripheral sound sources, positions for auxiliary sound sources located on or before or behind or within the projection of the hull with respect to the listener.

14. The apparatus of claim 1 ,
wherein the projector is configured to additionally shrink the projection of the hull such as towards a center of gravity of the hull or the projection by a variable or predetermined amount or by different variables or predetermined amounts in different directions such as a horizontal direction and a vertical direction.

15. The apparatus of claim 1 , wherein the sound position calculator is configured for calculating such that at least one additional auxiliary s

Assignees

• Fraunhofer Ges Forschung

Inventors

• Herre Jürgen
• Habets Emanuel
• Schlecht Sebastian
• Adami Alexander

Classifications

• H04S7/303 Primary

  Tracking of listener position or orientation · CPC title

• H04S2420/03

  Application of parametric coding in stereophonic audio systems · CPC title

• H04S2400/11

  Positioning of individual sound objects, e.g. moving airplane, within a sound field (H04S2420/13 takes precedence) · CPC title

• H04S2420/01

  Enhancing the perception of the sound image or of the spatial distribution using head related transfer functions [HRTF's] or equivalents thereof, e.g. interaural time difference [ITD] or interaural level difference [ILD] · CPC title