Patents by Inventor Per Ekstrand

Per Ekstrand 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: 20230197103
    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.
    Type: Application
    Filed: February 23, 2023
    Publication date: June 22, 2023
    Applicant: Dolby International AB
    Inventors: Kristofer KJOERLING, Lars VILLEMOES, Heiko PURNHAGEN, Per EKSTRAND
  • Patent number: 11676616
    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: Grant
    Filed: October 11, 2022
    Date of Patent: June 13, 2023
    Assignee: DOLBY INTERNATIONAL AB
    Inventors: Lars Villemoes, Heiko Purnhagen, Per Ekstrand
  • Patent number: 11664038
    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.
    Type: Grant
    Filed: June 2, 2022
    Date of Patent: May 30, 2023
    Assignee: Dolby International AB
    Inventors: Lars Villemoes, Heiko Purnhagen, Per Ekstrand
  • Publication number: 20230160015
    Abstract: The present invention relates to coding of audio signals, and in particular to high frequency reconstruction methods including a frequency domain harmonic transposer. A system and method for generating a high frequency component of a signal from a low frequency component of the signal is described.
    Type: Application
    Filed: January 19, 2023
    Publication date: May 25, 2023
    Applicant: Dolby International AB
    Inventors: Lars VILLEMOES, Per EKSTRAND
  • Patent number: 11657788
    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 ?f.
    Type: Grant
    Filed: December 13, 2021
    Date of Patent: May 23, 2023
    Assignee: DOLBY INTERNATIONAL AB
    Inventors: Per Ekstrand, Lars Villemoes, Per Hedelin
  • Patent number: 11646041
    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: Grant
    Filed: October 25, 2022
    Date of Patent: May 9, 2023
    Assignee: Dolby International AB
    Inventors: Kristofer Kjoerling, Lars Villemoes, Heiko Purnhagen, Per Ekstrand
  • Patent number: 11646040
    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: Grant
    Filed: October 25, 2022
    Date of Patent: May 9, 2023
    Assignee: Dolby International AB
    Inventors: Kristofer Kjoerling, Lars Villemoes, Heiko Purnhagen, Per Ekstrand
  • Patent number: 11626120
    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: Grant
    Filed: October 25, 2022
    Date of Patent: April 11, 2023
    Assignee: DOLBY INTERNATIONAL AB
    Inventors: Kristofer Kjoerling, Lars Villemoes, Heiko Purnhagen, Per Ekstrand
  • Patent number: 11626123
    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: Grant
    Filed: October 23, 2020
    Date of Patent: April 11, 2023
    Assignee: DOLBY INTERNATIONAL AB
    Inventors: Lars Villemoes, Heiko Purnhagen, Per Ekstrand
  • Patent number: 11626121
    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: Grant
    Filed: October 25, 2022
    Date of Patent: April 11, 2023
    Assignee: Dolby International AB
    Inventors: Kristofer Kjoerling, Lars Villemoes, Heiko Purnhagen, Per Ekstrand
  • Patent number: 11621013
    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: Grant
    Filed: October 11, 2022
    Date of Patent: April 4, 2023
    Assignee: DOLBY INTERNATIONAL AB
    Inventors: Lars Villemoes, Heiko Purnhagen, Per Ekstrand
  • Publication number: 20230087552
    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.
    Type: Application
    Filed: November 15, 2022
    Publication date: March 23, 2023
    Applicant: Dolby International AB
    Inventors: Kristofer KJOERLING, Lars VILLEMOES, Heiko PURNHAGEN, Per EKSTRAND
  • Patent number: 11605391
    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: Grant
    Filed: October 11, 2022
    Date of Patent: March 14, 2023
    Assignee: DOLBY INTERNATIONAL AB
    Inventors: Lars Villemoes, Heiko Purnhagen, Per Ekstrand
  • Publication number: 20230074883
    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.
    Type: Application
    Filed: October 21, 2022
    Publication date: March 9, 2023
    Inventors: Lars VILLEMOES, Per EKSTRAND, Sascha DISCH, Frederik NAGEL, Stephan WILDE
  • Patent number: 11594234
    Abstract: The present invention relates to transposing signals in time and/or frequency and in particular to coding of audio signals. More particular, the present invention relates to high frequency reconstruction (HFR) methods including a frequency domain harmonic transposer. A method and system for generating a transposed output signal from an input signal using a transposition factor T is described. The system comprises an analysis window of length La, extracting a frame of the input signal, and an analysis transformation unit of order M transforming the samples into M complex coefficients. M is a function of the transposition factor T. The system further comprises a nonlinear processing unit altering the phase of the complex coefficients by using the transposition factor T, a synthesis transformation unit of order M transforming the altered coefficients into M altered samples, and a synthesis window of length Ls, generating a frame of the output signal.
    Type: Grant
    Filed: September 27, 2022
    Date of Patent: February 28, 2023
    Assignee: Dolby International AB
    Inventors: Per Ekstrand, Lars Villemoes
  • Patent number: 11591657
    Abstract: The present invention relates to coding of audio signals, and in particular to high frequency reconstruction methods including a frequency domain harmonic transposer. A system and method for generating a high frequency component of a signal from a low frequency component of the signal is described.
    Type: Grant
    Filed: March 15, 2021
    Date of Patent: February 28, 2023
    Assignee: Dolby International AB
    Inventors: Lars Villemoes, Per Ekstrand
  • Publication number: 20230059049
    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: October 25, 2022
    Publication date: February 23, 2023
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Kristofer KJOERLING, Lars VILLEMOES, Heiko PURNHAGEN, Per EKSTRAND
  • Publication number: 20230049695
    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: October 25, 2022
    Publication date: February 16, 2023
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Kristofer KJOERLING, Lars VILLEMOES, Heiko PURNHAGEN, Per EKSTRAND
  • Publication number: 20230050996
    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: October 25, 2022
    Publication date: February 16, 2023
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Kristofer KJOERLING, Lars VILLEMOES, Heiko PURNHAGEN, Per EKSTRAND
  • Publication number: 20230049358
    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: October 25, 2022
    Publication date: February 16, 2023
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Kristofer KJOERLING, Lars VILLEMOES, Heiko PURNHAGEN, Per EKSTRAND