公开(公告)号：US09980073B2

公开(公告)日：2018-05-22

申请号：US15221354

申请日：2016-07-27

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Alexander Krüger ,  Sven Kordon ,  Johannes Boehm ,  Johann-Markus Batke

IPC: G10L19/00 ,  H04S3/00 ,  G10L19/008 ,  H04H20/89 ,  G10L19/20 ,  H04S3/02

CPC classification number: H04S3/008 ,  G10L19/008 ,  G10L19/20 ,  H04H20/89 ,  H04S3/02 ,  H04S2420/11

Abstract: A method and apparatus for decompressing a Higher Order Ambisonics (HOA) signal representation is disclosed. The apparatus includes an input interface that receives an encoded directional signal and an encoded ambient signal and an audio decoder that perceptually decodes the encoded directional signal and encoded ambient signal to produce a decoded directional signal and a decoded ambient signal, respectively. The apparatus further includes an extractor for obtaining side information related to the directional signal and an inverse transformer for converting the decoded ambient signal from a spatial domain to an HOA domain representation of the ambient signal. The apparatus also includes a synthesizer for recomposing a Higher Order Ambisonics (HOA) signal from the HOA domain representation of the ambient signal and the decoded directional signal. The side information includes a direction of the directional signal selected from a set of uniformly spaced directions.

公开(公告)号：US09913063B2

公开(公告)日：2018-03-06

申请号：US15650674

申请日：2017-07-14

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Sven Kordon ,  Alexander Krueger

IPC: H04R5/00 ,  H04S3/00 ,  G10L19/008

CPC classification number: H04S3/008 ,  G10L19/008 ,  H04S2420/03 ,  H04S2420/11 ,  H04S2420/13

Abstract: Higher Order Ambisonics represents three-dimensional sound independent of a specific loudspeaker set-up. However, transmission of an HOA representation results in a very high bit rate. Therefore compression with a fixed number of channels is used, in which directional and ambient signal components are processed differently. The ambient HOA component is represented by a minimum number of HOA coefficient sequences. The remaining channels contain either directional signals or additional coefficient sequences of the ambient HOA component, depending on what will result in optimum perceptual quality. This processing can change on a frame-by-frame basis.

公开(公告)号：US20180048974A1

公开(公告)日：2018-02-15

申请号：US15790375

申请日：2017-10-23

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Sven Kordon ,  Alexander Krueger

IPC: H04S3/00 ,  G10L19/008

CPC classification number: H04S3/008 ,  G10L19/008 ,  H04S2420/11

Abstract: There are two representations for Higher Order Ambisonics denoted HOA: spatial domain and coefficient domain. The invention generates from a coefficient domain representation a mixed spatial/coefficient domain representation, wherein the number of said HOA signals can be variable. A vector of coefficient domain signals is separated into a vector of coefficient domain signals having a constant number of HOA coefficients and a vector of coefficient domain signals having a variable number of HOA coefficients. The constant-number HOA coefficients vector is transformed to a corresponding spatial domain signal vector. In order to facilitate high-quality coding, without creating signal discontinuities the variable-number HOA coefficients vector of coefficient domain signals is adaptively normalised and multiplexed with the vector of spatial domain signals.

公开(公告)号：US09792924B2

公开(公告)日：2017-10-17

申请号：US15319707

申请日：2015-06-22

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Alexander Krueger ,  Sven Kordon

IPC: H04S5/02 ,  H04S3/00 ,  G10L19/20 ,  G10L19/008 ,  H04S3/02

CPC classification number: G10L19/20 ,  G10L19/008 ,  H04S3/02 ,  H04S2420/11

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 {β e) 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 (AA).

公开(公告)号：US12069465B2

公开(公告)日：2024-08-20

申请号：US18339368

申请日：2023-06-22

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Sven Kordon ,  Alexander Krueger ,  Oliver Wuebbolt

IPC: H04S3/00 ,  G10L19/008 ,  G10L19/24 ,  H04S7/00

CPC classification number: H04S3/008 ,  G10L19/008 ,  G10L19/24 ,  H04S7/30 ,  H04S2400/01 ,  H04S2420/11

Abstract: A method for compressing a HOA signal being an input HOA representation with input time frames (C(k)) of HOA coefficient sequences comprises spatial HOA encoding of the input time frames and subsequent perceptual encoding and source encoding. Each input time frame is decomposed (802) into a frame of predominant sound signals (XPS(k−1)) and a frame of an ambient HOA component ({tilde over (C)}AMB(k−1)). The ambient HOA component ({tilde over (C)}AMB(k−1)) comprises, in a layered mode, first HOA coefficient sequences of the input HOA representation (cn(k−1)) in lower positions and second HOA coefficient sequences (cAMB,n(k−1)) in remaining higher positions. The second HOA coefficient sequences are part of an HOA representation of a residual between the input HOA representation and the HOA representation of the predominant sound signals.

公开(公告)号：US11895477B2

公开(公告)日：2024-02-06

申请号：US17700390

申请日：2022-03-21

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Sven Kordon ,  Alexander Krueger

IPC: H04S3/00 ,  G10L19/008

CPC classification number: H04S3/008 ,  G10L19/008 ,  H04S2420/03 ,  H04S2420/11 ,  H04S2420/13

Abstract: Higher Order Ambisonics represents three-dimensional sound independent of a specific loudspeaker set-up. However, transmission of an HOA representation results in a very high bit rate. Therefore, compression with a fixed number of channels is used, in which directional and ambient signal components are processed differently. The ambient HOA component is represented by a minimum number of HOA coefficient sequences. The remaining channels contain either directional signals or additional coefficient sequences of the ambient HOA component, depending on what will result in optimum perceptual quality. This processing can change on a frame-by-frame basis.

公开(公告)号：US11830504B2

公开(公告)日：2023-11-28

申请号：US17957199

申请日：2022-09-30

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Sven Kordon ,  Alexander Krueger ,  Oliver Wuebbolt

IPC: G06F17/00 ,  G10L19/008 ,  H04S3/00 ,  G10L19/24

CPC classification number: G10L19/008 ,  G10L19/24 ,  H04S3/008 ,  H04S2400/01 ,  H04S2420/11

Abstract: Methods and apparatus for decoding a compressed Higher Order Ambisonics (HOA) representation of a sound or soundfield. The method may include receiving a bit stream containing the compressed HOA representation and decoding, based on a determination that there are multiple layers, the compressed HOA representation from the bitstream to obtain a sequence of decoded HOA representations. A first subset of the sequence of decoded HOA representations is determined based only on corresponding ambient HOA components. A second subset of the sequence of decoded HOA representations is determined based on corresponding ambient HOA components and corresponding predominant sound components. For a frame k, the sequence of decoded HOA representations are represented at least in part by








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where ĉAMB,n(k−1) corresponds to the corresponding ambient HOA components and ĉPS,n(k−1) corresponds to the corresponding predominant sound components.

公开(公告)号：US11792591B2

公开(公告)日：2023-10-17

申请号：US17548485

申请日：2021-12-10

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Alexander Krueger ,  Sven Kordon ,  Johannes Boehm ,  Johann-Markus Batke

IPC: G10L19/008 ,  H04S3/00 ,  H04H20/89 ,  G10L19/20 ,  H04S3/02

CPC classification number: H04S3/008 ,  G10L19/008 ,  G10L19/20 ,  H04H20/89 ,  H04S3/02 ,  H04S2420/11

Abstract: A method and apparatus for decompressing a Higher Order Ambisonics (HOA) signal representation is disclosed. The apparatus includes an input interface that receives an encoded directional signal and an encoded ambient signal and an audio decoder that perceptually decodes the encoded directional signal and encoded ambient signal to produce a decoded directional signal and a decoded ambient signal, respectively. The apparatus further includes an extractor for obtaining side information related to the directional signal and an inverse transformer for converting the decoded ambient signal from a spatial domain to an HOA domain representation of the ambient signal. The apparatus also includes a synthesizer for recomposing a Higher Order Ambisonics (HOA) signal from the HOA domain representation of the ambient signal and the decoded directional signal. The side information includes a direction of the directional signal selected from a set of uniformly spaced directions.

公开(公告)号：US11758344B2

公开(公告)日：2023-09-12

申请号：US17700228

申请日：2022-03-21

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Sven Kordon ,  Alexander Krueger

IPC: H04S3/00 ,  G10L19/008

CPC classification number: H04S3/008 ,  G10L19/008 ,  H04S2420/03 ,  H04S2420/11 ,  H04S2420/13

Abstract: Higher Order Ambisonics represents three-dimensional sound independent of a specific loudspeaker set-up. However, transmission of an HOA representation results in a very high bit rate. Therefore, compression with a fixed number of channels is used, in which directional and ambient signal components are processed differently. The ambient HOA component is represented by a minimum number of HOA coefficient sequences. The remaining channels contain either directional signals or additional coefficient sequences of the ambient HOA component, depending on what will result in optimum perceptual quality. This processing can change on a frame-by-frame basis.

公开(公告)号：US11546712B2

公开(公告)日：2023-01-03

申请号：US17532246

申请日：2021-11-22

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Alexander Krueger ,  Sven Kordon ,  Johannes Boehm

IPC: H04S7/00 ,  H04S3/00 ,  G10L19/008

Abstract: The invention improves HOA sound field representation compression and decompression. A decoder decodes compressed dominant directional signals and compressed residual component signals so as to provide decompressed dominant directional signals and decompressed time domain signals representing a residual HOA component in a spatial domain. A re-correlator re-correlates the decompressed time domain signals to obtain a corresponding reduced-order residual HOA component. A processor determines a decompressed residual HOA component based on the corresponding reduced-order residual HOA component, and determines predicted directional signals based on at least a parameter. The processor is further configured to determine an HOA sound field representation based on the decompressed dominant directional signals, the predicted directional signals, and the decompressed residual HOA component.