Patents by Inventor Kristofer Kjorling

Kristofer Kjorling 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: 20160086616
    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: November 9, 2015
    Publication date: March 24, 2016
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Barbara RESCH, Kristofer KJÖRLING, Lars VILLEMOES
  • Patent number: 9224403
    Abstract: In one aspect, the invention provides an audio encoding method characterized by a decision being made as to whether the device which will decode the resulting bit stream should apply post filtering including attenuation of interharmonic noise. Hence, the decision whether to use the post filter, which is encoded in the bit stream, is taken separately from the decision as to the most suitable coding mode. In another aspect, there is provided an audio decoding method with a decoding step followed by a post-filtering step, including interharmonic noise attenuation, and being characterized in a step of disabling the post filter in accordance with post filtering information encoded in the bit stream signal. Such a method is well suited for mixed-origin audio signals by virtue of its capability to deactivate the post filter in dependence of the post filtering information only, hence independently of factors such as the current coding mode.
    Type: Grant
    Filed: June 23, 2011
    Date of Patent: December 29, 2015
    Assignee: Dolby International AB
    Inventors: Barbara Resch, Kristofer Kjörling, Lars Villemoes
  • Patent number: 9218818
    Abstract: The present invention provides improvements to prior art audio codecs that generate a stereo-illusion through post-processing of a received mono signal. These improvements are accomplished by extraction of stereo-image describing parameters at the encoder side, which are transmitted and subsequently used for control of a stereo generator at the decoder side. Furthermore, the invention bridges the gap between simple pseudo-stereo methods, and current methods of true stereo-coding, by using a new form of parametric stereo coding. A stereo-balance parameter is introduced, which enables more advanced stereo modes, and in addition forms the basis of a new method of stereo-coding of spectral envelopes, of particular use in systems where guided HFR (High Frequency Reconstruction) is employed. As a special case, the application of this stereo-coding scheme in scalable HFR-based codecs is described.
    Type: Grant
    Filed: April 27, 2012
    Date of Patent: December 22, 2015
    Assignee: DOLBY INTERNATIONAL AB
    Inventors: Fredrik Henn, Kristofer Kjorling, Lars Liljeryd, Jonas Roden, Jonas Engdegard
  • Publication number: 20140074485
    Abstract: The present invention provides improvements to prior art audio codecs that generate a stereo-illusion through post-processing of a received mono signal. These improvements are accomplished by extraction of stereo-image describing parameters at the encoder side, which are transmitted and subsequently used for control of a stereo generator at the decoder side. Furthermore, the invention bridges the gap between simple pseudo-stereo methods, and current methods of true stereo-coding, by using a new form of parametric stereo coding. A stereo-balance parameter is introduced, which enables more advanced stereo modes, and in addition forms the basis of a new method of stereo-coding of spectral envelopes, of particular use in systems where guided HFR (High Frequency Reconstruction) is employed. As a special case, the application of this stereo-coding scheme in scalable HFR-based codecs is described.
    Type: Application
    Filed: November 12, 2013
    Publication date: March 13, 2014
    Inventors: Fredrik HENN, Kristofer KJORLING, Lars LILJERYD, Jonas RODEN, Jonas ENGDEGARD
  • Publication number: 20140074462
    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: November 14, 2013
    Publication date: March 13, 2014
    Applicant: Dolby International AB
    Inventors: Kristofer KJORLING, Lars VILLEMOES
  • Patent number: 8605911
    Abstract: The present invention provides improvements to prior art audio codecs that generate a stereo-illusion through post-processing of a received mono signal. These improvements are accomplished by extraction of stereo-image describing parameters at the encoder side, which are transmitted and subsequently used for control of a stereo generator at the decoder side. Furthermore, the invention bridges the gap between simple pseudo-stereo methods, and current methods of true stereo-coding, by using a new form of parametric stereo coding. A stereo-balance parameter is introduced, which enables more advanced stereo modes, and in addition forms the basis of a new method of stereo-coding of spectral envelopes, of particular use in systems where guided HFR (High Frequency Reconstruction) is employed. As a special case, the application of this stereo-coding scheme in scalable HFR-based codecs is described.
    Type: Grant
    Filed: October 30, 2009
    Date of Patent: December 10, 2013
    Assignee: Dolby International AB
    Inventors: Fredrik Henn, Kristofer Kjorling, Lars Liljeryd, Jonas Roden, Jonas Engdegard
  • Patent number: 8606587
    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: July 18, 2012
    Date of Patent: December 10, 2013
    Assignee: Dolby International AB
    Inventors: Kristofer Kjorling, Lars Villemoes
  • Patent number: 8498876
    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: July 18, 2012
    Date of Patent: July 30, 2013
    Assignee: Dolby International AB
    Inventors: Kristofer Kjorling, Lars Villemoes
  • Patent number: 8447621
    Abstract: The present invention proposes a new method and a new apparatus for enhancement of audio source coding systems utilizing high frequency reconstruction (HFR). It utilizes a detection mechanism on the encoder side to assess what parts of the spectrum will not be correctly reproduced by the HFR method in the decoder. Information on this is efficiently coded and sent to the decoder, where it is combined with the output of the HFR unit.
    Type: Grant
    Filed: August 9, 2011
    Date of Patent: May 21, 2013
    Assignee: Dolby International AB
    Inventors: Kristofer Kjörling, Per Ekstrand, Holger Hörich
  • Publication number: 20130096912
    Abstract: In one aspect, the invention provides an audio encoding method characterized by a decision being made as to whether the device which will decode the resulting bit stream Bitstream should apply post filtering including attenuation of interharmonic noise. Hence, the decision whether to use the post filter, which is encoded in the bit stream, is taken separately from the decision as to the most suitable coding mode. In another aspect, there is provided an audio decoding method with a decoding step followed by a post-filtering step, including interharmonic noise attenuation, and being characterized in a step of disabling the post filter in accordance with post filtering information encoded in the bit stream signal. Such a method is well suited for mixed-origin audio signals by virtue of its capability to deactivate the post filter in dependence of the post filtering information only, hence independently of factors such as the current coding mode.
    Type: Application
    Filed: June 23, 2011
    Publication date: April 18, 2013
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Barbara Resch, Kristofer Kjörling, Lars Villemoes
  • Patent number: 8412365
    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 10, 2010
    Date of Patent: April 2, 2013
    Assignee: Dolby International AB
    Inventors: Lars Liljeryd, Per Ekstrand, Fredrik Henn, Kristofer Kjorling
  • Publication number: 20120284034
    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: July 18, 2012
    Publication date: November 8, 2012
    Inventors: Kristofer KJORLING, Lars Villemoes
  • Publication number: 20120284033
    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: July 18, 2012
    Publication date: November 8, 2012
    Inventors: Kristofer KJORLING, Lars Villemoes
  • Publication number: 20120213378
    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. This is accomplished by means of frequency translation in the frequency domain with spectral envelope adjustment in the same domain. The proposed invention offers a low-complexity HFR method useful in speech and natural audio coding applications.
    Type: Application
    Filed: April 30, 2012
    Publication date: August 23, 2012
    Applicant: Dolby International AB
    Inventors: LARS LILJERYD, PER EKSTRAND, FREDERIK HENN, KRISTOFER KJORLING
  • Publication number: 20120213377
    Abstract: The present invention provides improvements to prior art audio codecs that generate a stereo-illusion through post-processing of a received mono signal. These improvements are accomplished by extraction of stereo-image describing parameters at the encoder side, which are transmitted and subsequently used for control of a stereo generator at the decoder side. Furthermore, the invention bridges the gap between simple pseudo-stereo methods, and current methods of true stereo-coding, by using a new form of parametric stereo coding. A stereo-balance parameter is introduced, which enables more advanced stereo modes, and in addition forms the basis of a new method of stereo-coding of spectral envelopes, of particular use in systems where guided HFR (High Frequency Reconstruction) is employed. As a special case, the application of this stereo-coding scheme in scalable HFR-based codecs is described.
    Type: Application
    Filed: April 27, 2012
    Publication date: August 23, 2012
    Inventors: Fredrik HENN, Kristofer Kjorling, Lars Liljeryd, Jonas Roden, Jonas Engdegard
  • Patent number: 8243936
    Abstract: The present invention provides improvements to prior art audio codecs that generate a stereo-illusion through post-processing of a received mono signal. These improvements are accomplished by extraction of stereo-image describing parameters at the encoder side, which are transmitted and subsequently used for control of a stereo generator at the decoder side. Furthermore, the invention bridges the gap between simple pseudo-stereo methods, and current methods of true stereo-coding, by using a new form of parametric stereo coding. A stereo-balance parameter is introduced, which enables more advanced stereo modes, and in addition forms the basis of a new method of stereo-coding of spectral envelopes, of particular use in systems where guided HFR (High Frequency Reconstruction) is employed. As a special case, the application of this stereo-coding scheme in scalable HFR-based codecs is described.
    Type: Grant
    Filed: October 30, 2009
    Date of Patent: August 14, 2012
    Assignee: Dolby International AB
    Inventors: Fredrik Henn, Kristofer Kjorling, Lars Liljeryd, Jonas Roden, Jonas Engdegard
  • Patent number: 8116460
    Abstract: The present invention provides improvements to prior art audio codecs that generate a stereo-illusion through post-processing of a received mono signal. These improvements are accomplished by extraction of stereo-image describing parameters at the encoder side, which are transmitted and subsequently used for control of a stereo generator at the decoder side. Furthermore, the invention bridges the gap between simple pseudo-stereo methods, and current methods of true stereo-coding, by using a new form of parametric stereo coding. A stereo-balance parameter is introduced, which enables more advanced stereo modes, and in addition forms the basis of a new method of stereo-coding of spectral envelopes, of particular use in systems where guided HFR (High Frequency Reconstruction) is employed. As a special case, the application of this stereo-coding scheme in scalable HFR-based codecs is described.
    Type: Grant
    Filed: September 28, 2005
    Date of Patent: February 14, 2012
    Assignee: Coding Technologies AB
    Inventors: Fredrik Henn, Kristofer Kjorling, Lars Liljeryd, Jonas Roden, Jonas Engdegard
  • Patent number: 8112284
    Abstract: The present invention proposes a new method and a new apparatus for enhancement of audio source coding systems utilizing high frequency reconstruction (HFR). It utilizes a detection mechanism on the encoder side to assess what parts of the spectrum will not be correctly reproduced by the HFR method in the decoder. Information on this is efficiently coded and sent to the decoder, where it is combined with the output of the HFR unit.
    Type: Grant
    Filed: November 19, 2008
    Date of Patent: February 7, 2012
    Assignee: Coding Technologies AB
    Inventors: Kristofer Kjörling, Per Ekstrand, Holger Hörich
  • Patent number: 8081763
    Abstract: The present invention provides improvements to prior art audio codecs that generate a stereo-illusion through post-processing of a received mono signal. These improvements are accomplished by extraction of stereo-image describing parameters at the encoder side, which are transmitted and subsequently used for control of a stereo generator at the decoder side. Furthermore, the invention bridges the gap between simple pseudo-stereo methods, and current methods of true stereo-coding, by using a new form of parametric stereo coding. A stereo-balance parameter is introduced, which enables more advanced stereo modes, and in addition forms the basis of a new method of stereo-coding of spectral envelopes, of particular use in systems where guided HFR (High Frequency Reconstruction) is employed. As a special case, the application of this stereo-coding scheme in scalable HFR-based codecs is described.
    Type: Grant
    Filed: July 2, 2009
    Date of Patent: December 20, 2011
    Assignee: Coding Technologies AB
    Inventors: Fredrik Henn, Kristofer Kjorling, Lars Liljeryd, Jonas Roden, Jonas Engdegard
  • Patent number: 8073144
    Abstract: The present invention provides improvements to prior art audio codecs that generate a stereo-illusion through post-processing of a received mono signal. These improvements are accomplished by extraction of stereo-image describing parameters at the encoder side, which are transmitted and subsequently used for control of a stereo generator at the decoder side. Furthermore, the invention bridges the gap between simple pseudo-stereo methods, and current methods of true stereo-coding, by using a new form of parametric stereo coding. A stereo-balance parameter is introduced, which enables more advanced stereo modes, and in addition forms the basis of a new method of stereo-coding of spectral envelopes, of particular use in systems where guided HFR (High Frequency Reconstruction) is employed. As a special case, the application of this stereo-coding scheme in scalable HFR-based codecs is described.
    Type: Grant
    Filed: September 27, 2005
    Date of Patent: December 6, 2011
    Assignee: Coding Technologies AB
    Inventors: Fredrik Henn, Kristofer Kjorling, Lars Liljeryd, Jonas Roden, Jonas Engdegard