Patents by Inventor Kristofer Kjoerling

Kristofer Kjoerling has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20210050022
    Abstract: The present document describes a method (400) for encoding a soundfield representation (SR) input signal (101, 301) describing a soundfield at a reference position, wherein the SR input signal (101, 301) comprises a plurality of channels for a plurality of different directivity patterns of the soundfield at the reference position. The method (400) comprises extracting (401) one or more audio objects (103, 303) from the SR input signal (101, 301). Furthermore, the method (400) comprises determining (402) a residual signal (102, 302) based on the SR input signal (101, 301) and based on the one or more audio objects (103, 303). The method (400) also comprises performing joint coding of the one or more audio objects (103, 303) and/or the residual signal (102, 302). In addition, the method (400) comprises generating (403) a bitstream (701) based on data generated in the context of joint coding of the one or more audio objects (103, 303) and/or the residual signal (102, 302).
    Type: Application
    Filed: January 17, 2019
    Publication date: February 18, 2021
    Applicants: DOLBY INTERNATIONAL AB, DOLBY LABORATORIES LICENSING CORPORATION
    Inventors: Kristofer KJOERLING, David S. MCGRATH, Heiko PURNHAGEN, Mark R.P. THOMAS
  • Publication number: 20210035592
    Abstract: In some embodiments, a pitch filter for filtering a preliminary audio signal generated from an audio bitstream is disclosed. The pitch filter has an operating mode selected from one of either: (i) an active mode where the preliminary audio signal is filtered using filtering information to obtain a filtered audio signal, and (ii) an inactive mode where the pitch filter is disabled. The preliminary audio signal is generated in an audio encoder or audio decoder having a coding mode selected from at least two distinct coding modes, and the pitch filter is capable of being selectively operated in either the active mode or the inactive mode while operating in the coding mode based on control information.
    Type: Application
    Filed: October 16, 2020
    Publication date: February 4, 2021
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Barbara RESCH, Kristofer KJÖRLING, Lars VILLEMOES
  • Patent number: 10893375
    Abstract: A method of encoding channel or object based input audio for playback, the method including the steps of: (a) initially rendering the channel or object based input audio into an initial output presentation; (b) determining an estimate of the dominant audio component from the channel or object based input audio and determining a series of dominant audio component weighting factors for mapping the initial output presentation into the dominant audio component; (c) determining an estimate of the dominant audio component direction or position; and (d) encoding the initial output presentation, the dominant audio component weighting factors, the dominant audio component direction or position as the encoded signal for playback.
    Type: Grant
    Filed: July 18, 2019
    Date of Patent: January 12, 2021
    Assignees: Dolby Laboratories Licensing Corporation, Dolby International AB
    Inventors: Dirk Jeroen Breebaart, David Matthew Cooper, Mark F. Davis, David S. McGrath, Kristofer Kjoerling, Harald Mundt, Rhonda J. Wilson
  • Publication number: 20200411019
    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.
    Type: Application
    Filed: January 28, 2019
    Publication date: December 31, 2020
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Kristofer KJOERLING, Lars VILLEMOES, Heiko PURNHAGEN, Per EKSTRAND
  • Publication number: 20200388294
    Abstract: The present invention relates to a new method and apparatus for improvement of High Frequency Reconstruction (HFR) techniques using frequency translation or folding or a combination thereof. The proposed invention is applicable to audio source coding systems, and offers significantly reduced computational complexity. This is accomplished by means of frequency translation or folding in the subband domain, preferably integrated with spectral envelope adjustment in the same domain. The concept of dissonance guard-band filtering is further presented. The proposed invention offers a low-complexity, intermediate quality HFR method useful in speech and natural audio coding applications.
    Type: Application
    Filed: June 23, 2020
    Publication date: December 10, 2020
    Applicant: Dolby International AB
    Inventors: Lars G. LILJERYD, Per EKSTRAND, Fredrik HENN, Kristofer KJOERLING
  • Publication number: 20200380999
    Abstract: The present invention proposes a new method for improving the performance of a real-valued filterbank based spectral envelope adjuster. By adaptively locking the gain values for adjacent channels dependent on the sign of the channels, as defined in the application, reduced aliasing is achieved. Furthermore, the grouping of the channels during gain-calculation, gives an improved energy estimate of the real valued subband signals in the filterbank.
    Type: Application
    Filed: June 14, 2020
    Publication date: December 3, 2020
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Kristofer KJOERLING, Lars VILLEMOES
  • Patent number: 10811023
    Abstract: The present document relates to time-alignment of encoded data of an audio encoder with associated metadata, such as spectral band replication (SBR) metadata. An audio decoder configured to determine a reconstructed frame of an audio signal from an access unit of a received data stream is described. The access unit comprises waveform data and metadata, wherein the waveform data and the metadata are associated with the same reconstructed frame of the audio signal. The audio decoder comprises a waveform processing path configured to generate a plurality of waveform subband signals from the waveform data, and a metadata processing path configured to generate decoded metadata from the metadata.
    Type: Grant
    Filed: September 29, 2017
    Date of Patent: October 20, 2020
    Assignee: Dolby International AB
    Inventors: Kristofer Kjoerling, Heiko Purnhagen, Jens Popp
  • Patent number: 10811024
    Abstract: In some embodiments, a pitch filter for filtering a preliminary audio signal generated from an audio bitstream is disclosed. The pitch filter has an operating mode selected from one of either: (i) an active mode where the preliminary audio signal is filtered using filtering information to obtain a filtered audio signal, and (ii) an inactive mode where the pitch filter is disabled. The preliminary audio signal is generated in an audio encoder or audio decoder having a coding mode selected from at least two distinct coding modes, and the pitch filter is capable of being selectively operated in either the active mode or the inactive mode while operating in the coding mode based on control information.
    Type: Grant
    Filed: March 12, 2019
    Date of Patent: October 20, 2020
    Assignee: Dolby International AB
    Inventors: Barbara Resch, Kristofer Kjörling, Lars Villemoes
  • Patent number: 10796703
    Abstract: Methods and systems encoding a stereo audio signal having a left channel and a right channel are disclosed. The system includes a downmixer for generating a downmix signal and a residual signal from the stereo audio signal in selected frequency bands representing only part of a used audio frequency range of the stereo audio signal, and a decision module for selecting, in a time variant manner, either left/right perceptual encoding or mid/side perceptual encoding. The system also includes a parameter estimator for estimating stereo parameters for reconstructing a stereo image of a portion of the stereo audio signal, and a perceptual encoder for performing either left/right perceptual encoding or mid/side perceptual encoding based on the selecting to generate an encoded output signal. Finally, the system includes a bitstream generator for creating a bitstream signal comprising the encoded output signal.
    Type: Grant
    Filed: September 3, 2019
    Date of Patent: October 6, 2020
    Assignee: Dolby International AB
    Inventors: Heiko Purnhagen, Pontus Carlsson, Kristofer Kjoerling
  • Publication number: 20200304913
    Abstract: A method and apparatus for reconstructing N audio channels from M audio channels is disclosed. The method includes receiving a bitstream containing an encoded audio signal representing the M audio channels and decoding the encoded audio signal to obtain a frequency domain representation of the M audio channels. The method further includes extracting a parameter from the bitstream and reconstructing at least one of the N audio channels using the parameter. The parameter represents an angle between two signals, at least one of which is included in the M audio channels.
    Type: Application
    Filed: April 13, 2020
    Publication date: September 24, 2020
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Heiko PURNHAGEN, Lars VILLEMOES, Jonas ENGDEGARD, Jonas ROEDEN, Kristofer KJOERLING
  • Publication number: 20200293272
    Abstract: In an audio encoder, for audio content received in a source audio format, default gains are generated based on a default dynamic range compression (DRC) curve, and non-default gains are generated for a non-default gain profile. Based on the default gains and non-default gains, differential gains are generated. An audio signal comprising the audio content, the default DRC curve, and differential gains is generated. In an audio decoder, the default DRC curve and the differential gains are identified from the audio signal. Default gains are re-generated based on the default DRC curve. Based on the combination of the re-generated default gains and the differential gains, operations are performed on the audio content extracted from the audio signal.
    Type: Application
    Filed: March 23, 2020
    Publication date: September 17, 2020
    Applicants: DOLBY LABORATORIES LICENSING CORPORATION, DOLBY INTERNATIONAL AB
    Inventors: Jeroen Koppens, Jeffrey Riedmiller, Kristofer Kjoerling, Alexander Stahlmann, Holger Hoerich, Alan J. Seefeldt
  • Publication number: 20200286497
    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.
    Type: Application
    Filed: March 23, 2020
    Publication date: September 10, 2020
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Heiko PURNHAGEN, Kristofer KJOERLING
  • Publication number: 20200275171
    Abstract: A method for providing media content within a media distribution network. The method comprises transforming source media content into an interim format, thereby providing transformed content. Furthermore, the method comprises storing the transformed content on at least one core storage unit. In addition, the method comprises receiving a request for the source media content from a client. The method further comprises encoding the transformed content or intermediate coded content derived therefrom into encoded content suitable for transmission over a core network and/or an edge network, as well as sending the encoded content via the core network and/or the edge network to the client.
    Type: Application
    Filed: July 26, 2018
    Publication date: August 27, 2020
    Applicants: DOLBY LABORATORIES LICENSING CORPORATION, DOLBY INTERNATIONAL AB
    Inventors: Jason Michael CLOUD, Jeffrey RIEDMILLER, Kristofer KJOERLING, Janusz KLEJSA
  • Publication number: 20200265844
    Abstract: There are provided decoding and encoding methods for encoding and decoding of multichannel audio content for playback on a speaker configuration with N channels. The decoding method comprises decoding, in a first decoding module, M input audio signals into M mid signals which are suitable for playback on a speaker configuration with M channels; and for each of the N channels in excess of M channels, receiving an additional input audio signal corresponding to one of the M mid signals and decoding the input audio signal and its corresponding mid signal so as to generate a stereo signal including a first and a second audio signal which are suitable for playback on two of the N channels of the speaker configuration.
    Type: Application
    Filed: February 25, 2020
    Publication date: August 20, 2020
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Heiko Purnhagen, Harald Mundt, Kristofer Kjoerling
  • Patent number: 10699724
    Abstract: The present invention relates to a new method and apparatus for improvement of High Frequency Reconstruction (HFR) techniques using frequency translation or folding or a combination thereof. The proposed invention is applicable to audio source coding systems, and offers significantly reduced computational complexity. This is accomplished by means of frequency translation or folding in the subband domain, preferably integrated with spectral envelope adjustment in the same domain. The concept of dissonance guard-band filtering is further presented. The proposed invention offers a low-complexity, intermediate quality HFR method useful in speech and natural audio coding applications.
    Type: Grant
    Filed: February 12, 2019
    Date of Patent: June 30, 2020
    Assignee: Dolby International AB
    Inventors: Lars G. Liljeryd, Per Ekstrand, Fredrik Henn, Kristofer Kjoerling
  • Publication number: 20200202878
    Abstract: On the basis of a bitstream (P), an n-channel audio signal (X) is reconstructed by deriving an m-channel core signal (Y) and multichannel coding parameters (?) from the bitstream, where 1?m<n. Also derived from the bitstream are pre-processing dynamic range control, DRC, parameters (DRC2) quantifying an encoder-side dynamic range limiting of the core signal. The n-channel audio signal is obtained by parametric synthesis in accordance with the multichannel coding parameters and while cancelling any encoder-side dynamic range limiting based on the pre-processing DRC parameters. In particular embodiments, the reconstruction further includes use of compensated post-processing DRC parameters quantifying a potential decoder-side dynamic range compression. Cancellation of an encoder-side range limitation and range compression are preferably performed by different decoder-side components. Cancellation and compression may be coordinated by a DRC pre-processor.
    Type: Application
    Filed: December 19, 2019
    Publication date: June 25, 2020
    Applicants: DOLBY LABORATORIES LICENSING CORPORATION, DOLBY INTERNATIONAL AB
    Inventors: Jeffrey RIEDMILLER, Karl J. ROEDEN, Kristofer KJOERLING, Heiko PURNHAGEN, Vinay MELKOTE, Leif SEHLSTROM
  • Patent number: 10685661
    Abstract: The present invention proposes a new method for improving the performance of a real-valued filterbank based spectral envelope adjuster. By adaptively locking the gain values for adjacent channels dependent on the sign of the channels, as defined in the application, reduced aliasing is achieved. Furthermore, the grouping of the channels during gain-calculation, gives an improved energy estimate of the real valued subband signals in the filterbank.
    Type: Grant
    Filed: August 7, 2019
    Date of Patent: June 16, 2020
    Assignee: Dolby International AB
    Inventors: Kristofer Kjoerling, Lars Villemoes
  • Patent number: 10623860
    Abstract: A method and apparatus for reconstructing N audio channels from M audio channels is disclosed. The method includes receiving a bitstream containing an encoded audio signal representing the M audio channels and decoding the encoded audio signal to obtain a frequency domain representation of the M audio channels. The method further includes extracting a parameter from the bitstream and reconstructing at least one of the N audio channels using the parameter. The parameter represents an angle between two signals, at least one of which is included in the M audio channels.
    Type: Grant
    Filed: September 26, 2019
    Date of Patent: April 14, 2020
    Assignee: Dolby International AB
    Inventors: Heiko Purnhagen, Lars Villemoes, Jonas Engdegard, Jonas Roeden, Kristofer Kjoerling
  • Patent number: 10606550
    Abstract: In an audio encoder, for audio content received in a source audio format, default gains are generated based on a default dynamic range compression (DRC) curve, and non-default gains are generated for a non-default gain profile. Based on the default gains and non-default gains, differential gains are generated. An audio signal comprising the audio content, the default DRC curve, and differential gains is generated. In an audio decoder, the default DRC curve and the differential gains are identified from the audio signal. Default gains are re-generated based on the default DRC curve. Based on the combination of the re-generated default gains and the differential gains, operations are performed on the audio content extracted from the audio signal.
    Type: Grant
    Filed: April 17, 2019
    Date of Patent: March 31, 2020
    Assignees: Dolby Laboratories Licensing Corporation, Dolby International AB
    Inventors: Jeroen Koppens, Jeffrey Riedmiller, Kristofer Kjoerling, Alexander Stahlmann, Holger Hoerich, Alan J. Seefeldt
  • Publication number: 20200098381
    Abstract: A method for decoding an encoded audio bitstream in an audio processing system is disclosed. The method includes extracting from the encoded audio bitstream a first waveform-coded signal comprising spectral coefficients corresponding to frequencies up to a first cross-over frequency for a time frame and performing parametric decoding at a second cross-over frequency for the time frame to generate a reconstructed signal. The second cross-over frequency is above the first cross-over frequency and the parametric decoding uses reconstruction parameters derived from the encoded audio bitstream to generate the reconstructed signal. The method also includes extracting from the encoded audio bitstream a second waveform-coded signal comprising spectral coefficients corresponding to a subset of frequencies above the first cross-over frequency for the time frame and interleaving the second waveform-coded signal with the reconstructed signal to produce an interleaved signal for the time frame.
    Type: Application
    Filed: October 4, 2019
    Publication date: March 26, 2020
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Kristofer KJOERLING, Heiko PURNHAGEN, Harald MUNDT, Karl Jonas ROEDEN, Leif SEHLSTROM