公开(公告)号：US11736890B2

公开(公告)日：2023-08-22

申请号：US17372833

申请日：2021-07-12

Applicant: Dolby Laboratories Licensing Corporation ,  DOLBY INTERNATIONAL AB

Inventor： Dirk Jeroen Breebaart ,  Lie Lu ,  Nicolas R. Tsingos ,  Antonio Mateos Sole

IPC: G10L19/20 ,  G10L19/018 ,  G10L19/00 ,  H04S3/00 ,  H04S7/00 ,  G10L19/008

CPC classification number: H04S7/308 ,  G10L19/00 ,  G10L19/008 ,  G10L19/018 ,  G10L19/20 ,  H04S3/002 ,  H04S2400/11 ,  H04S2400/13 ,  H04S2400/15 ,  H04S2420/03 ,  H04S2420/07

Abstract: Diffuse or spatially large audio objects may be identified for special processing. A decorrelation process may be performed on audio signals corresponding to the large audio objects to produce decorrelated large audio object audio signals. These decorrelated large audio object audio signals may be associated with object locations, which may be stationary or time-varying locations. For example, the decorrelated large audio object audio signals may be rendered to virtual or actual speaker locations. The output of such a rendering process may be input to a scene simplification process. The decorrelation, associating and/or scene simplification processes may be performed prior to a process of encoding the audio data.

公开(公告)号：US20230245667A1

公开(公告)日：2023-08-03

申请号：US18295701

申请日：2023-04-04

Applicant: DOLBY INTERNATIONAL AB

Inventor： Heiko PURNHAGEN ,  Kristofer KJOERLING

IPC: G10L19/06 ,  G10L19/02 ,  G10L19/008 ,  G10L25/06 ,  H04S1/00 ,  G10L19/16

CPC classification number: G10L19/06 ,  G10L19/02 ,  G10L19/008 ,  G10L25/06 ,  H04S1/007 ,  G10L19/0204 ,  G10L19/167 ,  H04S2400/03 ,  H04S2420/03 ,  G10L19/0212 ,  G10L19/265

Abstract: The present disclosure provides methods, devices and computer program products for encoding and decoding a stereo audio signal based on an input signal. According to the disclosure, a hybrid approach of using both parametric stereo coding and a discrete representation of the stereo audio signal is used which may improve the quality of the encoded and decoded audio for certain bitrates.

公开(公告)号：US20230245637A1

公开(公告)日：2023-08-03

申请号：US18194414

申请日：2023-03-31

Applicant: DOLBY INTERNATIONAL AB

Inventor： Per EKSTRAND ,  Lars VILLEMOES ,  Per HEDELIN

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

CPC classification number: G10H1/0091 ,  G10L21/038 ,  G10L19/265 ,  G10H1/125 ,  G10L21/0388

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：US20230238017A1

公开(公告)日：2023-07-27

申请号：US18192982

申请日：2023-03-30

Applicant: DOLBY INTERNATIONAL AB

Inventor： Lars VILLEMOES

IPC: G10L21/038 ,  G10L19/02 ,  G10L19/022 ,  G10L21/04 ,  G10L25/18 ,  G10L19/032

CPC classification number: G10L21/038 ,  G10L19/0204 ,  G10L19/022 ,  G10L21/04 ,  G10L25/18 ,  G10L19/032

Abstract: The present document relates to audio source coding systems which make use of a harmonic transposition method for high frequency reconstruction (HFR), as well as to digital effect processors, e.g. exciters, where generation of harmonic distortion add brightness to the processed signal, and to time stretchers where a signal duration is prolonged with maintained spectral content. A system and method configured to generate a time stretched and/or frequency transposed signal from an input signal is described. The system comprises an analysis filterbank configured to provide an analysis subband signal from the input signal; wherein the analysis subband signal comprises a plurality of complex valued analysis samples, each having a phase and a magnitude. Furthermore, the system comprises a subband processing unit configured to determine a synthesis subband signal from the analysis subband signal using a subband transposition factor Q and a subband stretch factor S. The subband processing unit performs a block based nonlinear processing wherein the magnitude of samples of the synthesis subband signal are determined from the magnitude of corresponding samples of the analysis subband signal and a predetermined sample of the analysis subband signal. In addition, the system comprises a synthesis filterbank configured to generate the time stretched and/or frequency transposed signal from the synthesis subband signal.

公开(公告)号：US20230229892A1

公开(公告)日：2023-07-20

申请号：US17927929

申请日：2021-05-31

Applicant: DOLBY INTERNATIONAL AB

Inventor： Arijit BISWAS ,  Simon PLAIN

IPC: G06N3/0455 ,  G10L19/26 ,  G10L25/30 ,  G10L25/69 ,  G06N3/082

CPC classification number: G06N3/0455 ,  G10L19/26 ,  G10L25/30 ,  G10L25/69 ,  G06N3/082

Abstract: Described herein is a method of determining parameters for a generative neural network for processing an audio signal, wherein the generative neural network includes an encoder stage mapping to a coded feature space and a decoder stage, each stage including a plurality of convolutional layers with one or more weight coefficients, the method comprising a plurality of cycles with sequential processes of: pruning the weight coefficients of either or both stages based on pruning control information, the pruning control information determining the number of weight coefficients that are pruned for respective convolutional layers; training the pruned generative neural network based on a set of training data; determining a loss for the trained and pruned generative neural network based on a loss function; and determining updated pruning control information based on the determined loss and a target loss. Further described are corresponding apparatus, programs, and computer-readable storage media.

公开(公告)号：US11705143B2

公开(公告)日：2023-07-18

申请号：US17887429

申请日：2022-08-13

Applicant: Dolby Laboratories Licensing Corporation ,  DOLBY INTERNATIONAL AB

Inventor： Dirk Jeroen Breebaart ,  David Matthew Cooper ,  Leif Jonas Samuelsson

IPC: G10L19/02 ,  H04S7/00 ,  G10L19/008

CPC classification number: G10L19/0212 ,  G10L19/008 ,  G10L19/0204 ,  H04S7/308 ,  H04R2460/03 ,  H04S2400/01 ,  H04S2420/01 ,  H04S2420/03 ,  H04S2420/07

Abstract: A method for representing a second presentation of audio channels or objects as a data stream, the method comprising the steps of: (a) providing a set of base signals, the base signals representing a first presentation of the audio channels or objects; (b) providing a set of transformation parameters, the transformation parameters intended to transform the first presentation into the second presentation; the transformation parameters further being specified for at least two frequency bands and including a set of multi-tap convolution matrix parameters for at least one of the frequency bands.

公开(公告)号：US20230209291A1

公开(公告)日：2023-06-29

申请号：US18117267

申请日：2023-03-03

Applicant: DOLBY INTERNATIONAL AB

Inventor： Lars VILLEMOES

IPC: H04S7/00 ,  G10L19/008

CPC classification number: H04S7/30 ,  G10L19/008 ,  H04S7/307 ,  H04S2400/01 ,  H04S2420/01 ,  H04S2420/03 ,  H04S2400/03

Abstract: A multi-channel decoder for generating a binaural signal from a downmix signal using upmix rule information on an energy-error introducing upmix rule for calculating a gain factor based on the upmix rule information and characteristics of head related transfer function based filters corresponding to upmix channels. The one or more gain factors are used by a filter processor for filtering the downmix signal so that an energy corrected binaural signal having a left binaural channel and a right binaural channel is obtained.

公开(公告)号：US20230198488A1

公开(公告)日：2023-06-22

申请号：US17921279

申请日：2021-05-17

Applicant: DOLBY INTERNATIONAL AB

Inventor： Stanislaw GORLOW ,  Robin THESING

IPC: H03G9/02 ,  H03G7/00

CPC classification number: H03G9/025 ,  H03G7/007

Abstract: The present document describes a dynamic range control unit (210) configured to apply dynamic range control, referred to as DRC, to an audio signal (211). The DRC unit (210) is configured to downsample a subband signal (212) derived from the audio signal (211), to provide a downsampled subband signal (321), to determine a DRC gain (329) based on the downsampled subband signal (321), and to apply the DRC gain (329) to the subband signal (212), to provide a compressed subband signal (213) of a compressed audio signal (214).

公开(公告)号：US20230197103A1

公开(公告)日：2023-06-22

申请号：US18113406

申请日：2023-02-23

Applicant: Dolby International AB

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

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

CPC classification number: G10L21/0388 ,  G10L19/02 ,  G10L19/008 ,  H04S3/008

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：US11676616B2

公开(公告)日：2023-06-13

申请号：US17963743

申请日：2022-10-11

Applicant: DOLBY INTERNATIONAL AB

Inventor： Lars Villemoes ,  Heiko Purnhagen ,  Per Ekstrand

IPC: G10L19/00

CPC classification number: G10L19/26 ,  G10L19/008 ,  G10L19/24

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.