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: 20190119753
    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: December 18, 2018
    Publication date: April 25, 2019
    Applicant: Dolby International AB
    Inventors: Lars Villemoes, Per Ekstrand
  • Patent number: 10262669
    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: December 3, 2018
    Date of Patent: April 16, 2019
    Assignee: Dolby International AB
    Inventors: Lars Villemoes, Heiko Purnhagen, Per Ekstrand
  • Patent number: 10262668
    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: March 10, 2016
    Date of Patent: April 16, 2019
    Assignee: Dolby International AB
    Inventors: Lars Villemoes, Heiko Purnhagen, Per Ekstrand
  • Publication number: 20190103123
    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: Application
    Filed: December 3, 2018
    Publication date: April 4, 2019
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Lars VILLEMOES, Heiko PURNHAGEN, Per EKSTRAND
  • Patent number: 10186280
    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: October 25, 2017
    Date of Patent: January 22, 2019
    Assignee: Dolby International AB
    Inventors: Lars Villemoes, Per Ekstrand
  • Patent number: 10170131
    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.
    Type: Grant
    Filed: September 30, 2015
    Date of Patent: January 1, 2019
    Assignee: Dolby International AB
    Inventors: Jeroen Koppens, Per Ekstrand
  • Publication number: 20180366130
    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: June 22, 2018
    Publication date: December 20, 2018
    Inventors: Lars VILLEMOES, Per EKSTRAND, Sascha DISCH, Frederik NAGEL, Stephan WILDE
  • Publication number: 20180352475
    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.
    Type: Application
    Filed: August 10, 2018
    Publication date: December 6, 2018
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Heiko PURNHAGEN, Per EKSTRAND
  • Patent number: 10134413
    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: March 10, 2016
    Date of Patent: November 20, 2018
    Assignee: Dolby International AB
    Inventors: Lars Villemoes, Heiko Purnhagen, Per Ekstrand
  • Publication number: 20180322889
    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: Application
    Filed: July 19, 2018
    Publication date: November 8, 2018
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Lars Villemoes, Heiko Purnhagen, Per Ekstrand
  • Publication number: 20180315434
    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: Application
    Filed: July 5, 2018
    Publication date: November 1, 2018
    Applicant: Dolby International AB
    Inventors: Per Ekstrand, Lars Villemoes
  • Publication number: 20180277128
    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: May 24, 2018
    Publication date: September 27, 2018
    Applicant: Dolby International AB
    Inventors: Lars G. Liljeryd, Per Ekstrand, Fredrik Henn, Kristofer Kjoerling
  • Patent number: 10057808
    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.
    Type: Grant
    Filed: May 2, 2017
    Date of Patent: August 21, 2018
    Assignee: Dolby International AB
    Inventors: Heiko Purnhagen, Per Ekstrand
  • Patent number: 10043526
    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: October 13, 2015
    Date of Patent: August 7, 2018
    Assignee: Dolby International AB
    Inventors: Per Ekstrand, Lars Villemoes
  • Patent number: 10032458
    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: Grant
    Filed: March 15, 2017
    Date of Patent: July 24, 2018
    Assignees: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V., Dolby International AB
    Inventors: Lars Villemoes, Per Ekstrand, Sascha Disch, Frederik Nagel, Stephan Wilde
  • Patent number: 10008213
    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: August 15, 2017
    Date of Patent: June 26, 2018
    Assignee: Dolby International AB
    Inventors: Lars G. Liljeryd, Per Ekstrand, Fredrik Henn, Kristofer Kjoerling
  • Publication number: 20180146288
    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.
    Type: Application
    Filed: January 22, 2018
    Publication date: May 24, 2018
    Applicant: Dolby International AB
    Inventor: Per Ekstrand
  • Publication number: 20180130480
    Abstract: Disclosed are some examples of systems, apparatus, methods and computer program products implementing techniques for extending the range of a set of decoded parameter values for a sequence of frequency bands in an identifiable time frame of an audio signal. In some implementations, the parameter values vary in relation to a sequence of time frames of the audio signal and in relation to a sequence of frequency bands in each time frame. In some implementations, it is determined that a decoded value corresponds to a minimum of a first range of values of a first coding protocol of a set of coding protocols. The determined value is modified to be below the minimum of the first range of values to produce an extended value. A modified set of decoded values including one or more extended values can thus be provided.
    Type: Application
    Filed: April 1, 2016
    Publication date: May 10, 2018
    Applicant: Dolby International AB
    Inventors: Heiko PURNHAGEN, Per EKSTRAND, Harald MUNDT, Klaus PEICHL
  • Publication number: 20180114514
    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: Application
    Filed: December 21, 2017
    Publication date: April 26, 2018
    Applicant: Dolby International AB
    Inventors: Per Ekstrand, Lars Villemoes, Per Hedelin
  • Patent number: 9918164
    Abstract: An apparatus and method are disclosed for filtering an audio signal. The apparatus includes an analysis filter bank, a high frequency reconstructor or parametric stereo processor, and a synthesis filter bank. The analysis filterbank receives real-valued time domain input audio samples and generates complex valued subband samples. The high frequency reconstructor or parametric stereo processor modifies at least some of the complex valued subband samples. The synthesis filter bank receives the modified complex valued subband samples and generates time domain output audio samples. The analysis filter bank comprises analysis filters that are complex exponential modulated versions of a prototype filter with an arbitrary phase shift to reduce a complexity of the filter bank.
    Type: Grant
    Filed: February 24, 2017
    Date of Patent: March 13, 2018
    Assignee: Dolby International AB
    Inventor: Per Ekstrand