Patents by Inventor Stefan DOEHLA

Stefan DOEHLA 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).

  • Patent number: 10861468
    Abstract: The apparatus for encoding a multi-channel signal having at least two channels, includes: a parameter determiner for determining a broadband alignment parameter and a plurality of narrowband alignment parameters from the multichannel signal; a signal aligner for aligning the at least two channels using the broadband alignment parameter and the plurality of narrowband alignment parameters to obtain aligned channels; a signal processor for calculating a mid-signal and a side signal using the aligned channels; a signal encoder for encoding the mid-signal to obtain an encoded mid-signal and for encoding the side signal to obtain an encoded side signal; and an output interface for generating an encoded multi-channel signal including the encoded mid-signal, the encoded side signal, information on the broadband alignment parameter and information on the plurality of narrowband alignment parameters.
    Type: Grant
    Filed: July 12, 2018
    Date of Patent: December 8, 2020
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.
    Inventors: Stefan Bayer, Eleni Fotopoulou, Markus Multrus, Guillaume Fuchs, Emmanuel Ravelli, Markus Schnell, Stefan Doehla, Wolfgang Jaegers, Martin Dietz, Goran Markovic
  • Publication number: 20200381001
    Abstract: Audio decoder device for decoding a bitstream, the audio decoder device including: a predictive decoder for producing a decoded audio frame from the bitstream, wherein the predictive decoder includes a parameter decoder for producing one or more audio parameters for the decoded audio frame from the bitstream and wherein the predictive decoder includes a synthesis filter device for producing the decoded audio frame by synthesizing the one or more audio parameters for the decoded audio frame; a memory device including one or more memories, wherein each of the memories is configured to store a memory state for the decoded audio frame, wherein the memory state for the decoded audio frame of the one or more memories is used by the synthesis filter device for synthesizing the one or more audio parameters for the decoded audio frame; and a memory state resampling device configured to determine the memory state for synthesizing the one or more audio parameters for the decoded audio frame, which has a sampling rate, f
    Type: Application
    Filed: August 18, 2020
    Publication date: December 3, 2020
    Inventors: Stefan DOEHLA, Guillaume FUCHS, Bernhard GRILL, Markus MULTRUS, Grzegorz PIETRZYK, Emmanuel RAVELLI, Markus SCHNELL
  • Patent number: 10854211
    Abstract: An apparatus for encoding a multi-channel signal including at least two channels includes a time-spectral converter for converting sequences of blocks of sampling values of the at least two channels into a frequency domain representation having sequences of blocks of spectral values for the at least two channels; a multi-channel processor for applying a joint multi-channel processing to the sequences of blocks of spectral values to obtain at least one result sequence of blocks of spectral values including information related to the at least two channels; a spectral-time converter for converting the result sequence of blocks of spectral values into a time domain representation including an output sequence of blocks of sampling values; and a core encoder for encoding the output sequence of blocks of sampling values to obtain an encoded multi-channel signal.
    Type: Grant
    Filed: April 4, 2019
    Date of Patent: December 1, 2020
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.
    Inventors: Guillaume Fuchs, Emmanuel Ravelli, Markus Multrus, Markus Schnell, Stefan Doehla, Martin Dietz, Goran Markovic, Eleni Fotopoulou, Stefan Bayer, Wolfgang Jaegers
  • Patent number: 10847166
    Abstract: A coding efficiency of coding spectral coefficients of a spectrum of an audio signal is increased by en/decoding a currently to be en/decoded spectral coefficient by entropy en/decoding and, in doing so, performing the entropy en/decoding depending, in a context-adaptive manner, on a previously en/decoded spectral coefficient, while adjusting a relative spectral distance between the previously en/decoded spectral coefficient and the currently en/decoded spectral coefficient depending on an information concerning a shape of the spectrum.
    Type: Grant
    Filed: October 10, 2018
    Date of Patent: November 24, 2020
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.
    Inventors: Guillaume Fuchs, Matthias Neusinger, Markus Multrus, Stefan Doehla
  • Publication number: 20200327896
    Abstract: The invention provides an audio encoder including a combination of a linear predictive coding filter having a plurality of linear predictive coding coefficients and a time-frequency converter, wherein the combination is configured to filter and to convert a frame of the audio signal into a frequency domain in order to output a spectrum based on the frame and on the linear predictive coding coefficients; a low frequency emphasizer configured to calculate a processed spectrum based on the spectrum, wherein spectral lines of the processed spectrum representing a lower frequency than a reference spectral line are emphasized; and a control device configured to control the calculation of the processed spectrum by the low frequency emphasizer depending on the linear predictive coding coefficients of the linear predictive coding filter.
    Type: Application
    Filed: June 11, 2020
    Publication date: October 15, 2020
    Inventors: Stefan DOEHLA, Bernhard GRILL, Christian HELMRICH, Nikolaus RETTELBACH
  • Publication number: 20200321014
    Abstract: A jitter buffer control for controlling a provision of a decoded audio content on the basis of an input audio content is configured to select a frame-based time scaling or a sample-based time scaling in a signal-adaptive manner. An audio decoder uses such a jitter buffer control.
    Type: Application
    Filed: June 11, 2020
    Publication date: October 8, 2020
    Inventors: Stefan REUSCHL, Stefan DOEHLA, Jérémie LECOMTE, Manuel JANDER
  • Publication number: 20200314505
    Abstract: Audio data processor, having: a receiver interface for receiving encoded audio data and metadata related to the encoded audio data; a metadata parser for parsing the metadata to determine an audio data manipulation possibility; an interaction interface for receiving an interaction input and for generating, from the interaction input, interaction control data related to the audio data manipulation possibility; and a data stream generator for obtaining the interaction control data and the encoded audio data and the metadata and for generating an output data stream, the output data stream having the encoded audio data, at least a portion of the metadata, and the interaction control data.
    Type: Application
    Filed: May 13, 2020
    Publication date: October 1, 2020
    Inventors: Stephan SCHREINER, Simone NEUKAM, Harald FUCHS, Jan PLOGSTIES, Stefan DOEHLA
  • Patent number: 10789963
    Abstract: The invention provides a decoder being configured for processing an encoded audio bitstream, wherein the decoder includes: a bitstream decoder configured to derive a decoded audio signal from the bitstream, wherein the decoded audio signal includes at least one decoded frame; a noise estimation device configured to produce a noise estimation signal containing an estimation of the level and/or the spectral shape of a noise in the decoded audio signal; a comfort noise generating device configured to derive a comfort noise signal from the noise estimation signal; and a combiner configured to combine the decoded frame of the decoded audio signal and the comfort noise signal in order to obtain an audio output signal.
    Type: Grant
    Filed: June 21, 2019
    Date of Patent: September 29, 2020
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.
    Inventors: Guillaume Fuchs, Anthony Lombard, Emmanuel Ravelli, Stefan Doehla, Jérémie Lecomte, Martin Dietz
  • Patent number: 10783898
    Abstract: Audio decoder device for decoding a bitstream, the audio decoder device including: a predictive decoder for producing a decoded audio frame from the bitstream, wherein the predictive decoder includes a parameter decoder for producing one or more audio parameters for the decoded audio frame from the bitstream and wherein the predictive decoder includes a synthesis filter device for producing the decoded audio frame by synthesizing the one or more audio parameters for the decoded audio frame; a memory device including one or more memories, wherein each of the memories is configured to store a memory state for the decoded audio frame, wherein the memory state for the decoded audio frame of the one or more memories is used by the synthesis filter device for synthesizing the one or more audio parameters for the decoded audio frame; and a memory state resampling device configured to determine the memory state for synthesizing the one or more audio parameters for the decoded audio frame, which has a sampling rate, f
    Type: Grant
    Filed: February 10, 2017
    Date of Patent: September 22, 2020
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.
    Inventors: Stefan Doehla, Guillaume Fuchs, Bernhard Grill, Markus Multrus, Grzegorz Pietrzyk, Emmanuel Ravelli, Markus Schnell
  • Publication number: 20200286498
    Abstract: The coding efficiency of an audio codec using a controllable—switchable or even adjustable—harmonic filter tool is improved by performing the harmonicity-dependent controlling of this tool using a temporal structure measure in addition to a measure of harmonicity in order to control the harmonic filter tool. In particular, the temporal structure of the audio signal is evaluated in a manner which depends on the pitch. This enables to achieve a situation-adapted control of the harmonic filter tool so that in situations where a control made solely based on the measure of harmonicity would decide against or reduce the usage of this tool, although using the harmonic filter tool would, in that situation, increase the coding efficiency, the harmonic filter tool is applied, while in other situations where the harmonic filter tool may be inefficient or even destructive, the control reduces the appliance of the harmonic filter tool appropriately.
    Type: Application
    Filed: May 27, 2020
    Publication date: September 10, 2020
    Inventors: Goran Markovic, Christian Helmrich, Emmanuel Ravelli, Manuel Jander, Stefan Doehla
  • Publication number: 20200273473
    Abstract: An apparatus for encoding directional audio coding parameters including diffuseness parameters and direction parameters includes: a parameter calculator for calculating the diffuseness parameters with a first time or frequency resolution and for calculating the direction parameters with a second time or frequency resolution; and a quantizer and encoder processor for generating a quantized and encoded representation of the diffuseness parameters and the direction parameters.
    Type: Application
    Filed: May 11, 2020
    Publication date: August 27, 2020
    Inventors: Guillaume FUCHS, Jürgen HERRE, Fabian KÜCH, Stefan DÖHLA, Markus MULTRUS, Oliver THIERGART, Oliver WÜBBOLT, Florin GHIDO, Stefan BAYER, Wolfgang JAEGERS
  • Publication number: 20200265851
    Abstract: An apparatus for encoding directional audio coding parameters having diffuseness parameters and direction parameters, has: a parameter quantizer for quantizing the diffuseness parameters and the direction parameters; a parameter encoder for encoding quantized diffuseness parameters and quantized direction parameters; and an output interface for generating an encoded parameter representation having information on encoded diffuseness parameters and encoded direction parameters.
    Type: Application
    Filed: May 6, 2020
    Publication date: August 20, 2020
    Inventors: Guillaume FUCHS, Jürgen HERRE, Fabian KÜCH, Stefan DÖHLA, Markus MULTRUS, Oliver THIERGART, Oliver WÜBBOLT, Florin GHIDO, Stefan BAYER, Wolfgang JAEGERS
  • Publication number: 20200234726
    Abstract: An audio decoder decodes a bit stream of encoded audio data, which bit stream represents a sequence of audio sample values and includes a plurality of frames, wherein each frame includes associated encoded audio sample values. The audio decoder includes a determiner configured to determine whether a frame of the encoded audio data is a special frame including encoded audio sample values associated with the special frame and additional information, wherein the additional information include encoded audio sample values of a number of frames preceding the special frame, wherein the encoded audio sample values of the preceding frames are encoded using the same codec configuration as the special frame, wherein the number of preceding frames is sufficient to initialize the decoder to be in a position to decode the audio sample values associated with the special frame if the special frame is the first frame upon start-up of the decoder.
    Type: Application
    Filed: April 6, 2020
    Publication date: July 23, 2020
    Inventors: Daniel FISCHER, Bernd CZELHAN, Max NEUENDORF, Nikolaus RETTELBACH, Ingo HOFMANN, Harald FUCHS, Stefan DOEHLA, Nikolaus FAERBER
  • Publication number: 20200227059
    Abstract: An apparatus for selecting one of a first encoding algorithm having a first characteristic and a second encoding algorithm having a second characteristic for encoding a portion of an audio signal to obtain an encoded version of the portion of the audio signal has a first estimator for estimating a first quality measure for the portion of the audio signal, which is associated with the first encoding algorithm, without actually encoding and decoding the portion of the audio signal using the first encoding algorithm. A second estimator is provided for estimating a second quality measure for the portion of the audio signal, which is associated with the second encoding algorithm, without actually encoding and decoding the portion of the audio signal using the second encoding algorithm. The apparatus has a controller for selecting the first or second encoding algorithms based on a comparison between the first and second quality measures.
    Type: Application
    Filed: March 31, 2020
    Publication date: July 16, 2020
    Inventors: Emmanuel RAVELLI, Stefan DOEHLA, Guillaume FUCHS, Eleni FOTOPOULOU, Christian HELMRICH
  • Patent number: 10714106
    Abstract: A jitter buffer control for controlling a provision of a decoded audio content on the basis of an input audio content is configured to select a frame-based time scaling or a sample-based time scaling in a signal-adaptive manner. An audio decoder uses such a jitter buffer control.
    Type: Grant
    Filed: March 2, 2018
    Date of Patent: July 14, 2020
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.
    Inventors: Stefan Reuschl, Stefan Doehla, Jérémie Lecomte, Manuel Jander
  • Publication number: 20200221230
    Abstract: An apparatus for generating a description of a combined audio scene, includes: an input interface for receiving a first description of a first scene in a first format and a second description of a second scene in a second format, wherein the second format is different from the first format; a format converter for converting the first description into a common format and for converting the second description into the common format, when the second format is different from the common format; and a format combiner for combining the first description in the common format and the second description in the common format to obtain the combined audio scene.
    Type: Application
    Filed: March 17, 2020
    Publication date: July 9, 2020
    Inventors: Guillaume FUCHS, Jürgen HERRE, Fabian KÜCH, Stefan DÖHLA, Markus MULTRUS, Oliver THIERGART, Oliver WÜBBOLT, Florin GHIDO, Stefan BAYER, Wolfgang JAEGERS
  • Patent number: 10706861
    Abstract: An apparatus for estimating an inter-channel time difference between a first channel signal and a second channel signal, includes: a calculator for calculating a cross-correlation spectrum for a time block from the first channel signal in the time block and the second channel signal in the time block; a spectral characteristic estimator for estimating a characteristic of a spectrum of the first channel signal or the second channel signal for the time block; a smoothing filter for smoothing the cross-correlation spectrum over time using the spectral characteristic to obtain a smoothed cross-correlation spectrum; and a processor for processing the smoothed cross-correlation spectrum to obtain the inter-channel time difference.
    Type: Grant
    Filed: July 13, 2018
    Date of Patent: July 7, 2020
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der andgewandten Forschung e.V.
    Inventors: Stefan Bayer, Eleni Fotopoulou, Markus Multrus, Guillaume Fuchs, Emmanuel Ravelli, Markus Schnell, Stefan Doehla, Wolfgang Jaegers, Martin Dietz, Goran Markovic
  • Patent number: 10706865
    Abstract: An apparatus for selecting one of a first encoding algorithm and a second encoding algorithm includes a filter configured to receive the audio signal, to reduce the amplitude of harmonics in the audio signal and to output a filtered version of the audio signal. First and second estimators are provided for estimating first and second quality measures in the form of SNRs of segmented SNRs associated with the first and second encoding algorithms without actually encoding and decoding the portion of the audio signal using the first and second encoding algorithms. A controller is provided for selecting the first encoding algorithm or the second encoding algorithm based on a comparison between the first quality measure and the second quality measure.
    Type: Grant
    Filed: January 24, 2019
    Date of Patent: July 7, 2020
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.
    Inventors: Emmanuel Ravelli, Markus Multrus, Stefan Doehla, Bernhard Grill, Manuel Jander
  • Patent number: 10692513
    Abstract: The invention provides an audio encoder including a combination of a linear predictive coding filter having a plurality of linear predictive coding coefficients and a time-frequency converter, wherein the combination is configured to filter and to convert a frame of the audio signal into a frequency domain in order to output a spectrum based on the frame and on the linear predictive coding coefficients; a low frequency emphasizer configured to calculate a processed spectrum based on the spectrum, wherein spectral lines of the processed spectrum representing a lower frequency than a reference spectral line are emphasized; and a control device configured to control the calculation of the processed spectrum by the low frequency emphasizer depending on the linear predictive coding coefficients of the linear predictive coding filter.
    Type: Grant
    Filed: April 18, 2018
    Date of Patent: June 23, 2020
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.
    Inventors: Stefan Doehla, Bernhard Grill, Christian Helmrich, Nikolaus Rettelbach
  • Publication number: 20200194013
    Abstract: An apparatus for estimating an inter-channel time difference between a first channel signal and a second channel signal, includes: a calculator for calculating a cross-correlation spectrum for a time block from the first channel signal in the time block and the second channel signal in the time block; a spectral characteristic estimator for estimating a characteristic of a spectrum of the first channel signal or the second channel signal for the time block; a smoothing filter for smoothing the cross-correlation spectrum over time using the spectral characteristic to obtain a smoothed cross-correlation spectrum; and a processor for processing the smoothed cross-correlation spectrum to obtain the inter-channel time difference.
    Type: Application
    Filed: February 19, 2020
    Publication date: June 18, 2020
    Inventors: Stefan BAYER, Eleni FOTOPOULOU, Markus MULTRUS, Guillaume FUCHS, Emmanuel RAVELLI, Markus SCHNELL, Stefan DOEHLA, Wolfgang JAEGERS, Martin DIETZ, Goran MARKOVIC