Patents by Inventor Leif Sehlström
Leif Sehlström 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).
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Publication number: 20250166648Abstract: 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: ApplicationFiled: November 25, 2024Publication date: May 22, 2025Applicants: DOLBY LABORATORIES LICENSING CORPORATION, DOLBY INTERNATIONAL ABInventors: Jeffrey RIEDMILLER, Karl J. ROEDEN, Kristofer KJOERLING, Heiko PURNHAGEN, Vinay MELKOTE, Leif SEHLSTROM
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Patent number: 12293768Abstract: 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: GrantFiled: November 8, 2023Date of Patent: May 6, 2025Assignee: Dolby International ABInventors: Kristofer Kjörling, Heiko Purnhagen, Harald Mundt, Karl Jonas Roeden, Leif Sehlström
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Patent number: 12175992Abstract: 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: GrantFiled: July 19, 2023Date of Patent: December 24, 2024Assignees: DOLBY LABORATORIES LICENSING CORPORATION, DOLBY INTERNATIONAL ABInventors: Jeffrey Riedmiller, Karl J. Roeden, Kristofer Kjoerling, Heiko Purnhagen, Vinay Melkote, Leif Sehlstrom
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Publication number: 20240153517Abstract: 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: ApplicationFiled: November 8, 2023Publication date: May 9, 2024Applicant: Dolby International ABInventors: Kristofer Kjörling, Heiko Purnhagen, Harald Mundt, Karl Jonas Roeden, Leif Sehlström
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Patent number: 11894005Abstract: An audio communication endpoint receives a bitstream containing spectral components representing spectral content of an audio signal, wherein the spectral components relate to a first range extending up to a first break frequency, above which any spectral components are unassigned. The endpoint adapts the received bitstream in accordance with a second range extending up to a second break frequency by removing spectral components or adding neutral-valued spectral components relating to a range between the first and second break frequencies. The endpoint then attenuates spectral content in a neighbourhood of the least of the first and second break frequencies for thereby achieving a gradual spectral decay. After this, reconstructing the audio signal is reconstructed by an inverse transform operating on spectral components relating to said second range in the adapted and attenuated received bitstream. At small computational expense, the endpoint may to adapt to different sample rates in received bitstreams.Type: GrantFiled: November 15, 2019Date of Patent: February 6, 2024Assignees: DOLBY LABORATORIES LICENSING CORPORATION, DOLBY INTERNATIONAL ABInventors: Heiko Purnhagen, Leif Sehlstrom, Lars Villemoes, Glenn N. Dickins, Mark S Vinton
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Publication number: 20240018844Abstract: 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 (a) 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: ApplicationFiled: July 19, 2023Publication date: January 18, 2024Applicants: DOLBY LABORATORIES LICENSING CORPORATION, DOLBY INTERNATIONAL ABInventors: Jeffrey RIEDMILLER, Karl J. ROEDEN, Kristofer KJOERLING, Heiko PURNHAGEN, Vinay MELKOTE, Leif SEHLSTROM
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Patent number: 11830510Abstract: 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: GrantFiled: August 31, 2021Date of Patent: November 28, 2023Assignee: Dolby International ABInventors: Kristofer Kjoerling, Heiko Purnhagen, Harald Mundt, Karl Jonas Roeden, Leif Sehlstrom
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Patent number: 11708741Abstract: 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: GrantFiled: March 15, 2021Date of Patent: July 25, 2023Assignees: DOLBY LABORATORIES LICENSING CORPORATION, DOLBY INTERNATIONAL ABInventors: Jeffrey Riedmiller, Karl J. Roeden, Kristofer Kjoerling, Heiko Purnhagen, Vinay Melkote, Leif Sehlstrom
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Patent number: 11545166Abstract: A technique including receiving and decoding a coded bitstream encoded with audio content including first audio objects corresponding to a first media content type of two consecutive media content types and second audio objects corresponding to a second media content type of the two consecutive media content types, and audio metadata corresponding to the audio content. The audio metadata including first and second audio object gains, for the first and second audio objects, generated in part based on a first fading curve of the first media content type and a second fading curve of the second media content type, respectively. The technique further includes applying the first and second audio object gains to the first and second audio objects, and rendering a sound field represented by the first audio object with the applied first audio object gain and the second audio object with the applied second audio object gain.Type: GrantFiled: July 1, 2020Date of Patent: January 3, 2023Assignee: Dolby International ABInventors: Alexander Stahlmann, Reinhold Boehm, Mark C. Leddy, Karsten Linzmeier, Vinay Mathew, Simon Plain, Heiko Purnhagen, Leif Sehlström, Robin Thesing
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Publication number: 20220059110Abstract: 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: ApplicationFiled: August 31, 2021Publication date: February 24, 2022Applicant: DOLBY INTERNATIONAL ABInventors: Kristofer KJOERLING, Heiko PURNHAGEN, Harald MUNDT, Karl Jonas ROEDEN, Leif SEHLSTROM
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Patent number: 11114107Abstract: 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: GrantFiled: October 4, 2019Date of Patent: September 7, 2021Assignee: Dolby International ABInventors: Kristofer Kjoerling, Heiko Purnhagen, Harald Mundt, Karl Jonas Roeden, Leif Sehlstrom
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Publication number: 20210270106Abstract: 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 (a) 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: ApplicationFiled: March 15, 2021Publication date: September 2, 2021Applicants: DOLBY LABORATORIES LICENSING CORPORATION, DOLBY INTERNATIONAL ABInventors: Jeffrey RIEDMILLER, Karl J. ROEDEN, Kristofer KJOERLING, Heiko PURNHAGEN, Vinay MELKOTE, Leif SEHLSTROM
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Patent number: 10950252Abstract: 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 (a) 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: GrantFiled: December 19, 2019Date of Patent: March 16, 2021Assignees: Dolby Laboratories Licensing Corporation, Dolby International ABInventors: Jeffrey Riedmiller, Karl J. Roeden, Kristofer Kjoerling, Heiko Purnhagen, Vinay Melkote, Leif Sehlstrom
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Publication number: 20210005211Abstract: A technique including receiving and decoding a coded bitstream encoded with audio content including first audio objects corresponding to a first media content type of two consecutive media content types and second audio objects corresponding to a second media content type of the two consecutive media content types, and audio metadata corresponding to the audio content. The audio metadata including first and second audio object gains, for the first and second audio objects, generated in part based on a first fading curve of the first media content type and a second fading curve of the second media content type, respectively. The technique further includes applying the first and second audio object gains to the first and second audio objects, and rendering a sound field represented by the first audio object with the applied first audio object gain and the second audio object with the applied second audio object gain.Type: ApplicationFiled: July 1, 2020Publication date: January 7, 2021Applicant: DOLBY INTERNATIONAL ABInventors: Alexander Stahlmann, Reinhold Boehm, Mark C. Leddy, Karsten Linzmeier, Vinay Mathew, Simon Plain, Heiko Purnhagen, Leif Sehlström, Robin Thesing
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Publication number: 20200202878Abstract: 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: ApplicationFiled: December 19, 2019Publication date: June 25, 2020Applicants: DOLBY LABORATORIES LICENSING CORPORATION, DOLBY INTERNATIONAL ABInventors: Jeffrey RIEDMILLER, Karl J. ROEDEN, Kristofer KJOERLING, Heiko PURNHAGEN, Vinay MELKOTE, Leif SEHLSTROM
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Publication number: 20200098381Abstract: 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: ApplicationFiled: October 4, 2019Publication date: March 26, 2020Applicant: DOLBY INTERNATIONAL ABInventors: Kristofer KJOERLING, Heiko PURNHAGEN, Harald MUNDT, Karl Jonas ROEDEN, Leif SEHLSTROM
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Publication number: 20200082836Abstract: An audio communication endpoint receives a bitstream containing spectral components representing spectral content of an audio signal, wherein the spectral components relate to a first range extending up to a first break frequency, above which any spectral components are unassigned. The endpoint adapts the received bitstream in accordance with a second range extending up to a second break frequency by removing spectral components or adding neutral-valued spectral components relating to a range between the first and second break frequencies. The endpoint then attenuates spectral content in a neighbourhood of the least of the first and second break frequencies for thereby achieving a gradual spectral decay. After this, reconstructing the audio signal is reconstructed by an inverse transform operating on spectral components relating to said second range in the adapted and attenuated received bitstream. At small computational expense, the endpoint may to adapt to different sample rates in received bitstreams.Type: ApplicationFiled: November 15, 2019Publication date: March 12, 2020Applicant: DOLBY LABORATORIES LICENSING CORPORATIONInventors: Heiko PURNHAGEN, Leif SEHLSTROM, Lars VILLEMOES, Glenn N. DICKINS, Mark S. VINTON
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Patent number: 10522163Abstract: 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 (a) 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: GrantFiled: July 17, 2019Date of Patent: December 31, 2019Assignees: Dolby Laboratories Licensing Corporation, Dolby International ABInventors: Jeffrey Riedmiller, Karl J. Roeden, Kristofer Kjoerling, Heiko Purnhagen, Vinay Melkote, Leif Sehlstrom
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Patent number: 10482891Abstract: An audio communication endpoint receives a bitstream containing spectral components representing spectral content of an audio signal, wherein the spectral components relate to a first range extending up to a first break frequency, above which any spectral components are unassigned. The endpoint adapts the received bitstream in accordance with a second range extending up to a second break frequency by removing moving spectral components or adding neutral-valued spectral components relating to a range between the first and second break frequencies. The endpoint then attenuates spectral content in a neighbourhood of the least of the first and second break frequencies for thereby achieving a gradual spectral decay. After this, reconstructing the audio signal is reconstructed by an inverse transform operating on spectral components relating to said second range in the adapted and attenuated received bitstream.Type: GrantFiled: January 10, 2018Date of Patent: November 19, 2019Assignees: Dolby Laboratories Licensing Corporation, Dolby International ABInventors: Heiko Purnhagen, Leif Sehlstrom, Lars Villemoes, Glenn N. Dickins, Mark S. Vinton
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Publication number: 20190341066Abstract: 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: ApplicationFiled: July 17, 2019Publication date: November 7, 2019Applicants: DOLBY LABORATORIES LICENSING CORPORATION, DOLBY INTERNATIONAL ABInventors: Jeffrey RIEDMILLER, Karl J. ROEDEN, Kristofer KJOERLING, Heiko PURNHAGEN, Vinay MELKOTE, Leif SEHLSTROM