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

Voiceage Corporation

Friedrich-Alexander-Universitat Erlangen-Nürnberg

Stefan Geyersberger

Nikolaus Rettelbach

Bernhard Grill

Guillaume Fuchs

Juergen Herre

Markus Multrus

Harald Popp

Johannes Hilpert

Max Neuendorf

Ralf Geiger

Gerald Schuller

Stefan Wabnik

Jens Hirschfeld

Stefan Bayer

Ulrich Kraemer

Redwan Salami

Bruno Bessette

Philippe Gournay

Roch Lefebvre

Jimmy Lapierre

Claus Spenger

Virgilio Bacigalupo

Andreas Hoelzer

Yoshikazu Yokotani

Jérémie Lecomte

Markus Schnell

Emmanuel Ravelli

Bernd Edler

Oliver Hellmuth

Manfred Lutzky

Adrian Tomasek

Andreas Hölzer

Sascha Disch

Jürgen Herre

Andreas Walther

Wolfgang Fiesel

Christiaan Janssen

Jin Woong Kim

Jin Woo Hong

Frederik Nagel

Dae Young Jang

Goran Markovic

Ralph Sperschneider

Marc Gayer

Kyeong Ok Kang

Michael Schug

Christian Uhle

Christian Ertel

Markus Lohwasser

Falko Ridderbusch

Albert Heuberger

Jin Suk Kwak

Young Kwon Lim

Alexander Tschekalinskij

Andreas Walter

Oliver Moser

Harald Gernhardt

Michael Haertl

Johann Hilpert

Martin Weishart

Sung Han Kim

Nikolaus Rettlebach

Ulrich KRÄMER

An audio encoder has a first information sink oriented encoding branch such as a spectral domain encoding branch, a second information source or SNR oriented encoding branch such as an LPC-domain encoding branch, and a switch for switching between the first and second encoding branches, the second encoding branch having a converter into a specific domain different from the spectral domain such as an LPC analysis stage generating an excitation signal, and the second encoding branch having a specific domain coding branch such as LPC domain processing branch, and a specific spectral domain coding branch such as LPC spectral domain processing branch, and an additional switch for switching between the specific domain coding branch and the specific spectral domain coding branch. An audio decoder has a first domain decoder, a second domain decoder, and a third domain decoder as well as two cascaded switches for switching between the decoders.

Low bitrate audio encoding/decoding scheme having cascaded switches

An encoder for providing an audio stream on the basis of a transform-domain representation of an input audio signal includes a quantization error calculator configured to determine a multi-band quantization error over a plurality of frequency bands of the input audio signal for which separate band gain information is available. The encoder also includes an audio stream provider for providing the audio stream such that the audio stream includes information describing an audio content of the frequency bands and information describing the multi-band quantization error. A decoder for providing a decoded representation of an audio signal on the basis of an encoded audio stream representing spectral components of frequency bands of the audio signal includes a noise filler for introducing noise into spectral components of a plurality of frequency bands to which separate frequency band gain information is associated on the basis of a common multi-band noise intensity value.

Audio encoder, audio decoder, methods for encoding and decoding an audio signal, audio stream and a computer program

An encoder provides an audio stream based on a transform-domain representation of an input audio signal and includes a quantization error calculator configured to determine a multi-band quantization error over a plurality of frequency bands of the input audio signal for which separate band gain information is available. The encoder also includes an audio stream provider for providing the audio stream such that the audio stream includes information describing an audio content of the frequency bands and information describing the multi-band quantization error. A decoder provides a decoded representation of an audio signal based on an encoded audio stream representing spectral components of frequency bands of the audio signal and includes a noise filler for introducing noise into spectral components of a plurality of frequency bands to which separate frequency band gain information is associated on the basis of a common multi-band noise intensity value.

An audio encoder for encoding segments of coefficients, the segments of coefficients representing different time or frequency resolutions of a sampled audio signal, the audio encoder including a processor for deriving a coding context for a currently encoded coefficient of a current segment based on a previously encoded coefficient of a previous segment, the previously encoded coefficient representing a different time or frequency resolution than the currently encoded coefficient. The audio encoder further includes an entropy encoder for encoding entropy the current coefficient based on the coding context to obtain an encoded audio stream.

Audio entropy encoder/decoder with different spectral resolutions and transform lengths and upsampling and/or downsampling

An audio encoder for encoding segments of coefficients, the segments of coefficients representing different time or frequency resolutions of a sampled audio signal, the audio encoder including a processor for deriving a coding context for a currently encoded coefficient of a current segment based on a previously encoded coefficient of a previous segment, the previously encoded coefficient representing a different time or frequency resolution than the currently encoded coefficient. The audio encoder further includes an entropy encoder for entropy encoding the current coefficient based on the coding context to obtain an encoded audio stream.

An encoder for providing an audio stream on the basis of a transform- domain representation of an input audio signal includes a quantization error calculator configured to determine a multi-band quantization error over a plurality of frequency bands of the input audio signal for which separate band gain information is available. The encoder also includes an audio stream provider for providing the audio stream such that the audio stream includes information describing an audio content of the frequency bands and information describing the multi-band quantization error. A decoder for providing a decoded representation of an audio signal on the basis of an encoded audio stream representing spectral components of frequency bands of the audio signal includes a noise filler for introducing noise into spectral components of a plurality of frequency bands to which separate frequency band gain information is associated on the basis of a common multi-band noise intensity value.

Audio entropy encoder/decoder with coding context and coefficient selection

An apparatus for decoding data segments representing a time-domain data stream, a data segment being encoded in the time domain or in the frequency domain, a data segment being encoded in the frequency domain having successive blocks of data representing successive and overlapping blocks of time-domain data samples. The apparatus includes a time-domain decoder for decoding a data segment being encoded in the time domain and a processor for processing the data segment being encoded in the frequency domain and output data of the time-domain decoder to obtain overlapping time-domain data blocks. The apparatus further includes an overlap/add-combiner for combining the overlapping time-domain data blocks to obtain a decoded data segment of the time-domain data stream.

Encoder, decoder and methods for encoding and decoding data segments representing a time-domain data stream

Growing community of inventors

Wuerzburg, Germany

Stefan Geyersberger