公开(公告)号：US20220180849A1

公开(公告)日：2022-06-09

申请号：US17549661

申请日：2021-12-13

Applicant: Dolby International AB

Inventor： Per EKSTRAND ,  Lars VILLEMOES ,  Per HEDELIN

IPC: G10H1/00 ,  G10L21/038 ,  G10L19/26 ,  G10H1/12

Abstract: The present document relates to audio coding systems which make use of a harmonic transposition method for high frequency reconstruction (HFR), and to digital effect processors, e.g. so-called exciters, where generation of harmonic distortion adds brightness to the processed signal. In particular, a system configured to generate a high frequency component of a signal from a low frequency component of the signal is described. The system may comprise an analysis filter bank (501) configured to provide a set of analysis subband signals from the low frequency component of the signal; wherein the set of analysis subband signals comprises at least two analysis subband signals; wherein the analysis filter bank (501) has a frequency resolution of Δf. The system further comprises a nonlinear processing unit (502) configured to determine a set of synthesis subband signals from the set of analysis subband signals using a transposition order P; wherein the set of synthesis subband signals comprises a portion of the set of analysis subband signals phase shifted by an amount derived from the transposition order P; and a synthesis filter bank (504) configured to generate the high frequency component of the signal from the set of synthesis subband signals; wherein the synthesis filter bank (504) has a frequency resolution of FΔf; with F being a resolution factor, with F≥1; wherein the transposition order P is different from the resolution factor F.

公开(公告)号：US20220059111A1

公开(公告)日：2022-02-24

申请号：US17461092

申请日：2021-08-30

Applicant: Dolby International AB

Inventor： Per EKSTRAND

IPC: G10L21/00 ,  G06F17/10 ,  H03H17/02 ,  G10L19/02 ,  G10L19/26 ,  H04R3/04 ,  G06F17/11 ,  G10L19/008 ,  H04S7/00

Abstract: An apparatus and method are disclosed for processing an audio signal. The apparatus includes an input interface, a digital filterbank having an analysis part and a synthesis part, a first phase shifter, a spectral envelope adjuster, a second phase shifter, and an output interface. The first phase shifter and the second phase shifter reduce a complexity of the digital filterbank, which includes both analysis and synthesis filters that are complex-exponential modulated versions of a prototype filter.

公开(公告)号：US20210082451A1

公开(公告)日：2021-03-18

申请号：US17050669

申请日：2019-04-25

Applicant: Dolby International AB

Inventor： Kristofer KJOERLING ,  Lars VILLEMOES ,  Heiko PURNHAGEN ,  Per EKSTRAND

IPC: G10L21/0388 ,  G10L19/008 ,  G10L19/02 ,  H04S3/00

Abstract: A method for decoding an encoded audio bitstream is disclosed. The method includes receiving the encoded audio bitstream and decoding the audio data to generate a decoded lowband audio signal. The method further includes extracting high frequency reconstruction metadata and filtering the decoded lowband audio signal with an analysis filterbank to generate a filtered lowband audio signal. The method also includes extracting a flag indicating whether either spectral translation or harmonic transposition is to be performed on the audio data and regenerating a highband portion of the audio signal using the filtered lowband audio signal and the high frequency reconstruction metadata in accordance with the flag. The high frequency regeneration is performed as a post-processing operation with a delay of 3010 samples per audio channel.

公开(公告)号：US20180366130A1

公开(公告)日：2018-12-20

申请号：US16016284

申请日：2018-06-22

Applicant: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V. ,  Dolby International AB

Inventor： Lars VILLEMOES ,  Per EKSTRAND ,  Sascha DISCH ,  Frederik NAGEL ,  Stephan WILDE

IPC: G10L19/008 ,  G10L21/038 ,  G10L19/02 ,  G10L21/04

Abstract: An apparatus for processing an input audio signal relies on a cascade of filterbanks, the cascade having a synthesis filterbank for synthesizing an audio intermediate signal from the input audio signal, the input audio signal being represented by a plurality of first subband signals generated by an analysis filterbank, wherein a number of filterbank channels of the synthesis filterbank is smaller than a number of channels of the analysis filterbank. The apparatus furthermore has a further analysis filterbank for generating a plurality of second subband signals from the audio intermediate signal, wherein the further analysis filterbank has a number of channels being different from the number of channels of the synthesis filterbank, so that a sampling rate of a subband signal of the plurality of second subband signals is different from a sampling rate of a first subband signal of the plurality of first subband signals.

公开(公告)号：US20180352475A1

公开(公告)日：2018-12-06

申请号：US16101220

申请日：2018-08-10

Applicant: DOLBY INTERNATIONAL AB

Inventor： Heiko PURNHAGEN ,  Per EKSTRAND

IPC: H04W28/06

CPC classification number: H04W28/065 ,  G10L19/008 ,  G10L19/035 ,  G10L19/038 ,  H04S1/007 ,  H04S2420/03 ,  H04W28/0215

Abstract: The present disclosure provides methods, devices and computer program products for non-uniform quantization of parameters relating to parametric spatial coding of audio signals. The disclosure further relates to a method and apparatus for reconstructing an audio object in an audio decoding system taking the non-uniformly quantized parameters into account. According to the disclosure, such an approach renders it possible to reduce bit consumption without substantially reducing the quality of the reconstructed audio object.

公开(公告)号：US20180025738A1

公开(公告)日：2018-01-25

申请号：US15546965

申请日：2016-03-10

Applicant: DOLBY INTERNATIONAL AB

Inventor： Lars VILLEMOES ,  Heiko PURNHAGEN ,  Per EKSTRAND

IPC: G10L19/16 ,  G10L19/24 ,  G10L19/035 ,  G10L21/038

CPC classification number: G10L19/167 ,  G10L19/035 ,  G10L19/24 ,  G10L21/038

Abstract: Embodiments relate to an audio processing unit that includes a buffer, bitstream payload deformatter, and a decoding subsystem. The buffer stores at least one block of an encoded audio bitstream. The block includes a fill element that begins with an identifier followed by fill data. The fill data includes at least one flag identifying whether enhanced spectral band replication (eSBR) processing is to be performed on audio content of the block. A corresponding method for decoding an encoded audio bitstream is also provided.

公开(公告)号：US20170309288A1

公开(公告)日：2017-10-26

申请号：US15513543

申请日：2015-09-30

Applicant: DOLBY INTERNATIONAL AB

Inventor： Jeroen KOPPENS ,  Per EKSTRAND

IPC: G10L21/02 ,  H04S3/00

CPC classification number: G10L21/0205 ,  G10L19/008 ,  G10L21/0316 ,  H04S3/008 ,  H04S2400/01 ,  H04S2400/03 ,  H04S2420/03

Abstract: There is provided a method for enhancing dialog in a decoder of an audio system. The method comprises receiving a plurality of downmix signals being a downmix of a larger plurality of channels; receiving parameters for dialog enhancement being defined with respect to a subset of the plurality of channels that is downmixed into a subset of the plurality of downmix signals; upmixing the subset of downmix signals parametrically in order to reconstruct the subset of the plurality of channels with respect to which the parameters for dialog enhancement are defined; applying dialog enhancement to the subset of the plurality of channels with respect to which the parameters for dialog enhancement are defined using the parameters for dialog enhancement to provide at least one dialog enhanced signal; and subjecting the at least one dialog enhanced signal to mixing to provide dialog enhanced versions of the subset of downmix signals.

公开(公告)号：US20170238208A1

公开(公告)日：2017-08-17

申请号：US15584534

申请日：2017-05-02

Applicant: DOLBY INTERNATIONAL AB

Inventor： Heiko PURNHAGEN ,  Per EKSTRAND

IPC: H04W28/06 ,  G10L19/008 ,  H04W28/02 ,  G10L19/035

CPC classification number: H04W28/065 ,  G10L19/008 ,  G10L19/035 ,  G10L19/038 ,  H04S1/007 ,  H04S2420/03 ,  H04W28/0215

Abstract: The present disclosure provides methods, devices and computer program products for non-uniform quantization of parameters relating to parametric spatial coding of audio signals. The disclosure further relates to a method and apparatus for reconstructing an audio object in an audio decoding system taking the non-uniformly quantized parameters into account. According to the disclosure, such an approach renders it possible to reduce bit consumption without substantially reducing the quality of the reconstructed audio object.

公开(公告)号：US20160217800A1

公开(公告)日：2016-07-28

申请号：US14916534

申请日：2014-09-08

Applicant: DOLBY INTERNATIONAL AB

Inventor： Heiko PURNHAGEN ,  Per EKSTRAND

IPC: G10L19/035 ,  H04S1/00

CPC classification number: H04W28/065 ,  G10L19/008 ,  G10L19/035 ,  G10L19/038 ,  H04S1/007 ,  H04S2420/03 ,  H04W28/0215

Abstract: The present disclosure provides methods, devices and computer program products for non-uniform quantization of parameters relating to parametric spatial coding of audio signals. The disclosure further relates to a method and apparatus for reconstructing an audio object in an audio decoding system taking the non-uniformly quantized parameters into account. According to the disclosure, such an approach renders it possible to reduce bit consumption without substantially reducing the quality of the reconstructed audio object.

Abstract translation: 本公开提供了用于与音频信号的参数空间编码相关的参数的非均匀量化的方法，设备和计算机程序产品。 本发明还涉及一种在考虑到非均匀量化参数的音频解码系统中重建音频对象的方法和装置。 根据本公开，这种方法使得可以在不显着降低重建的音频对象的质量的情况下减少比特消耗。