Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.V.

Stefan Döhla

Guillaume Fuchs

Markus Multrus

Stefan Bayer

Oliver Thiergart

Fabian Küch

Jürgen Herre

Florin Ghido

Wolfgang Jaegers

Srikanth Korse

Oliver Wübbolt

Jan Büthe

Alexandre Bouthéon

Andrea Eichenseer

Jérémie Lecomte

Martin Dietz

Eleni Fotopoulou

Franz Reutelhuber

Manuel Jander

Stefan Reuschl

Emmanuel Ravelli

Bernhard Grill

Christian Helmrich

Nikolaus Rettelbach

Markus Schnell

Max Neuendorf

Goran Markovic

Harald Fuchs

Manfred Lutzky

Ralph Sperschneider

Jan Plogsties

Daniel Fischer

Nikolaus Farber

Grzegorz Pietrzyk

Stephan Schreiner

Bernd Czelhan

Simone Neukam

Ingo Hofmann

Pallavi Maben

Anthony Lombard

Markus Prosch

Birgit Bartel-Kurz

Stefan Krägeloh

Jan Frederik Kiene

Dominik Häussler

Frederick Melville

Dennis Rosenberger

Archit Tamarapu

Nikolaus Färber

Oliver WÜBBOLT

Wolfgang JÄGERS

Simone FÜG

Ralf Sperschneider

An audio quantizer for quantizing a plurality of audio information items has: a first stage vector quantizer for quantizing the plurality of audio information items to determine a first stage vector quantization result and a plurality of intermediate quantized items corresponding to the first stage vector quantization result; a residual item determiner for calculating a plurality of residual items from the plurality of intermediate quantized items and the plurality of audio information items; and a second stage vector quantizer for quantizing the plurality of residual items to obtain a second stage vector quantization result, wherein the first stage vector quantization result and the second stage vector quantization result are a quantized representation of the plurality of audio information items.

Audio quantizer and audio dequantizer and related methods

Apparatus for processing an audio scene representing a sound field, the audio scene having information on a transport signal and a first set of parameters. The apparatus has a parameter processor for processing the first set of parameters to obtain a second set of parameters, wherein the parameter processor is configured to calculate at least one raw parameter for each output time frame using at least one parameter of the first set of parameters for the input time frame, to calculate a smoothing information such as a factor for each raw parameter in accordance with a smoothing rule, and to apply a corresponding smoothing information to the corresponding raw parameter to derive the parameter of the second set of parameters for the output time frame. The apparatus further has an output interface for generating a processed audio scene using the second set of parameters and the information on the transport signal.

Apparatus, method, or computer program for processing an encoded audio scene using a parameter smoothing

Apparatus for processing an audio scene representing a sound field, the audio scene comprising information on a transport signal and a set of parameters. The apparatus comprising an output interface for generating a processed audio scene using the set of parameters and the information on the transport signal, wherein the output interface is configured to generate a raw representation of two or more channels using the set of parameters and the transport signal and a multichannel enhancer for generating an enhancement representation of the two or more channels using the transport signal, and a signal combiner for combining the raw representation of the two or more channels and the enhancement representation of the two or more channels to obtain the processed audio scene.

Apparatus, method, or computer program for processing an encoded audio scene using a bandwidth extension

An apparatus generating a sound field description includes an input signal analyzer acquiring diffuseness data from the input signal; a sound component generator for generating, from the input signal, one or more sound field components of a first group of sound field components comprising for each sound field component a direct component and a diffuse component, and for generating, from the input signal, a second group of sound field components comprising only a direct component. The sound component generator is configured to perform an energy compensation when generating the first group of sound field components, the energy compensation depending on the diffuseness data and at least one of a number of sound field components in the second group, a number of diffuse components in the first group, a maximum order of sound field components of the first group and a maximum order of sound field components of the second group.

Apparatus, method and computer program for encoding, decoding, scene processing and other procedures related to DirAC based spatial audio coding using diffuse compensation

An apparatus for generating a sound field description using an input signal having a mono-signal or a multi-channel signal includes: an input signal analyzer for analyzing the input signal to derive direction data and diffuseness data; a low-order components generator for generating a low-order sound field description from the input signal up to a predetermined order and mode; a mid-order components generator for generating a mid-order sound field description above the predetermined order or at the predetermined order and above the predetermined mode and below or at a first truncation order using a synthesis of at least one direct portion and of at least one diffuse portion using the direction data and the diffuseness data; and a high-order components generator for generating a high-order sound field description having a component above the first truncation order using a synthesis of at least one direct portion.

Apparatus, method and computer program for encoding, decoding, scene processing and other procedures related to DirAC based spatial audio coding using low-order, mid-order and high-order components generators

An apparatus for encoding a spatial audio representation representing an audio scene to obtain an encoded audio signal includes: a transport representation generator for generating a transport representation from the spatial audio representation, and for generating transport metadata related to the generation of the transport representation or indicating one or more directional properties of the transport representation; and an output interface for generating the encoded audio signal, the encoded audio signal including information on the transport representation, and information on the transport metadata.

Apparatus and method for encoding a spatial audio representation or apparatus and method for decoding an encoded audio signal using transport metadata and related computer programs

An apparatus for estimating an inter-channel time difference between a first channel signal and a second channel signal, includes a signal analyzer for estimating a signal characteristic of the first channel signal or the second channel signal or both signals or a signal derived from the first channel signal or the second channel signal; 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 weighter for weighting a smoothed or non-smoothed cross-correlation spectrum to obtain a weighted cross correlation spectrum using a first weighting procedure or using a second weighting procedure depending on a signal characteristic estimated by the signal analyzer, wherein the first weighting procedure is different from the second weighting procedure; and a processor for processing the weighted cross-correlation spectrum to obtain the inter-channel time difference.

Apparatus, method or computer program for estimating an inter-channel time difference

An audio encoder for encoding audio input data has: a preprocessor for preprocessing the audio input data to obtain audio data to be coded; a coder processor for coding the audio data to be coded; and a controller for controlling the coder processor so that, depending on a first signal characteristic of a first frame of the audio data to be coded, a number of audio data items of the audio data to be coded by the coder processor for the first frame is reduced compared to a second signal characteristic of a second frame, and a first number of information units used for coding the reduced number of audio data items for the first frame is stronger enhanced compared to a second number of information units for the second frame.

Audio encoder with a signal-dependent number and precision control, audio decoder, and related methods and computer programs

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.

Apparatus and method for encoding or decoding directional audio coding parameters using different time/frequency resolutions

An apparatus for encoding directional audio coding parameters comprising diffuseness parameters and direction parameters having 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.

Apparatus and method for encoding or decoding directional audio coding parameters using quantization and entropy coding

What is described is a method for loss concealment of spatial audio parameters, the spatial audio parameters having at least a direction of arrival information; the method having the following steps:

Packet loss concealment for DirAC based spatial audio coding

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.

Apparatus, method and computer program for encoding, decoding, scene processing and other procedures related to DirAC based spatial audio coding

An apparatus for generating a sound field description using an input signal having a mono-signal or a multi-channel signal comprises: an input signal analyzer for analyzing the input signal to derive direction data and diffuseness data; a low-order components generator for generating a low-order sound field description from the input signal up to a predetermined order and mode; a mid-order components generator for generating a mid-order sound field description above the predetermined order or at the predetermined order and above the predetermined mode and below or at a first truncation order using a synthesis of at least one direct portion and of at least one diffuse portion using the direction data and the diffuseness data; and a high-order components generator for generating a high-order sound field description having a component above the first truncation order using a synthesis of at least one direct portion.

An apparatus for generating a sound field description from an input signal having at least two channels has: an input signal analyzer for obtaining direction data and diffuseness data from the input signal; an estimator for estimating a first energy- or amplitude-related measure for an omnidirectional component derived from the input signal and for estimating a second energy- or amplitude-related measure for a directional component derived from the input signal, and a sound component generator for generating sound field components of the sound field, wherein the sound component generator is configured to perform an energy compensation of the directional component using the first energy- or amplitude-related measure, the second energy- or amplitude-related measure, the direction data and the diffuseness data.

Apparatus, method and computer program for encoding, decoding, scene processing and other procedures related to DirAC based spatial audio coding using direct component compensation

Growing community of inventors

Erlangen, Germany

Stefan Döhla