公开(公告)号：US12236962B2

公开(公告)日：2025-02-25

申请号：US18464505

申请日：2023-09-11

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Sven Kordon ,  Alexander Krueger ,  Oliver Wuebbolt

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

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 c ^ ~ n ( k - 1 ) = { c ^ AMB , n ( k - 1 ) for ⁢ n ⁢ in ⁢ the ⁢ first ⁢ subset c ^ n ( k - 1 ) = c ^ PS , n ( k - 1 ) + c ^ AMB , n ( k - 1 ) , for ⁢ n ⁢ in ⁢ the ⁢ second ⁢ subset 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：US20210126649A1

公开(公告)日：2021-04-29

申请号：US17092648

申请日：2020-11-09

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Oliver Wuebbolt

IPC: H03M7/40 ,  H04N19/124 ,  H04N19/182

Abstract: The invention proposes a method and a device for arithmetic encoding of a current spectral coefficient using preceding spectral coefficients. Said preceding spectral coefficients are already encoded and both, said preceding and current spectral coefficients, are comprised in one or more quantized spectra resulting from quantizing time-frequency-transform of video, audio or speech signal sample values.
Said method comprises processing the preceding spectral coefficients, using the processed preceding spectral coefficients for determining a context class being one of at least two different context classes, using the determined context class and a mapping from the at least two different context classes to at least two different probability density functions for determining the probability density function, and arithmetic encoding the current spectral coefficient based on the determined probability density function wherein processing the preceding spectral coefficients comprises non-uniformly quantizing absolutes of the preceding spectral coefficients for use in determining of the context class.

公开(公告)号：US20200126579A1

公开(公告)日：2020-04-23

申请号：US16719806

申请日：2019-12-18

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Sven Kordon ,  Alexander Krueger ,  Oliver Wuebbolt

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

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. For coding, portions of the original HOA representation are predicted from the directional signal components. This prediction provides side information which is required for a corresponding decoding. By using some additional specific purpose bits, a known side information coding processing is improved in that the required number of bits for coding that side information is reduced on average.

公开(公告)号：US10147437B2

公开(公告)日：2018-12-04

申请号：US15956295

申请日：2018-04-18

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Alexander Krueger ,  Sven Kordon ,  Oliver Wuebbolt

IPC: H04R5/00 ,  G10L19/20 ,  G10L19/008 ,  H04S3/00

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. For coding, portions of the original HOA representation are predicted from the directional signal components. This prediction provides side information which is required for a corresponding decoding. By using some additional specific purpose bits, a known side information coding processing is improved in that the required number of bits for coding that side information is reduced on average.

公开(公告)号：US20220352900A1

公开(公告)日：2022-11-03

申请号：US17854866

申请日：2022-06-30

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Oliver Wuebbolt

IPC: H03M7/40 ,  H04N19/124 ,  H04N19/182

Abstract: The invention proposes a method and a device for arithmetic encoding of a current spectral coefficient using preceding spectral coefficients. Said preceding spectral coefficients are already encoded and both, said preceding and current spectral coefficients, are comprised in one or more quantized spectra resulting from quantizing time-frequency-transform of video, audio or speech signal sample values.
Said method comprises processing the preceding spectral coefficients, using the processed preceding spectral coefficients for determining a context class being one of at least two different context classes, using the determined context class and a mapping from the at least two different context classes to at least two different probability density functions for determining the probability density function, and arithmetic encoding the current spectral coefficient based on the determined probability density function wherein processing the preceding spectral coefficients comprises non-uniformly quantizing absolutes of the preceding spectral coefficients for use in determining of the context class.

公开(公告)号：US11462222B2

公开(公告)日：2022-10-04

申请号：US16892154

申请日：2020-06-03

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Sven Kordon ,  Alexander Krueger ,  Oliver Wuebbolt

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

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 c ^ ~ n ⁡ ( k - 1 ) = ⁢ { c ^ A ⁢ M ⁢ B , n ⁡ ( k - 1 ) for ⁢ ⁢ n ⁢ ⁢ in ⁢ ⁢ the ⁢ ⁢ first ⁢ ⁢ subset ⁢ c ^ n ⁡ ( k - 1 ) = c ^ P ⁢ S , n ⁡ ( k - 1 ) + c ^ A ⁢ M ⁢ B , n ⁡ ( k - 1 ) ⁢ , for ⁢ ⁢ n ⁢ ⁢ in ⁢ ⁢ the ⁢ ⁢ second ⁢ ⁢ subset ⁢ 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：US11381249B2

公开(公告)日：2022-07-05

申请号：US17092648

申请日：2020-11-09

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Oliver Wuebbolt

IPC: H04N11/02 ,  H03M7/40 ,  H04N19/124 ,  H04N19/182

Abstract: The invention proposes a method and a device for arithmetic encoding of a current spectral coefficient using preceding spectral coefficients. The preceding spectral coefficients are already encoded, and both the preceding and current spectral coefficients are comprised in one or more quantized spectra resulting from quantizing a time-frequency-transform of video, audio or speech signal sample values.

公开(公告)号：US20210058729A1

公开(公告)日：2021-02-25

申请号：US17010827

申请日：2020-09-03

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Sven Kordon ,  Alexander Krueger ,  Oliver Wuebbolt

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

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：US10714112B2

公开(公告)日：2020-07-14

申请号：US16719806

申请日：2019-12-18

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Sven Kordon ,  Alexander Krueger ,  Oliver Wuebbolt

IPC: H04R5/00 ,  G10L19/20 ,  G10L19/008 ,  H04S3/00

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. For coding, portions of the original HOA representation are predicted from the directional signal components. This prediction provides side information which is required for a corresponding decoding. By using some additional specific purpose bits, a known side information coding processing is improved in that the required number of bits for coding that side information is reduced on average.

公开(公告)号：US10679634B2

公开(公告)日：2020-06-09

申请号：US16186765

申请日：2018-11-12

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Sven Kordon ,  Alexander Krueger ,  Oliver Wuebbolt

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

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 c ^ ~ n ⁡ ( k - 1 ) = { c ^ AMB , n ⁡ ( k - 1 ) for ⁢ ⁢ n ⁢ ⁢ in ⁢ ⁢ the ⁢ ⁢ first ⁢ ⁢ subset c ^ n ⁡ ( k - 1 ) = c ^ PS , n ⁡ ( k - 1 ) + c ^ AMB , n ⁡ ( k - 1 ) , for ⁢ ⁢ n ⁢ ⁢ in ⁢ ⁢ the ⁢ ⁢ second ⁢ ⁢ subset where ĉAMB,n(k−1) corresponds to the corresponding ambient HOA components and ĉPS,n(k−1) corresponds to the corresponding predominant sound components.