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

Florian Schuh

Johannes Hilpert

Nikolaus Rettelbach

Sascha Dick

Richard Fueg

Bernhard Grill

Achim Kuntz

Christian Ertel

Christian Borss

Michael Fischer

Tobias Schwegler

Matthias Neusinger

Christian Helmrich

Frederik Nagel

Bernd Edler

Richard FÜG

An apparatus for encoding a multi-channel signal having at least three channels includes an iteration processor, a channel encoder and an output interface. The iteration processor is configured to calculate inter-channel correlation values between each pair of the at least three channels, for selecting a pair including a highest value or including a value above a threshold, and for processing the selected pair using a multi-channel processing operation to derive first multi-channel parameters for the selected pair and to derive first processed channels. The iteration processor is configured to perform the calculating, the selecting and the processing using at least one of the processed channels to derive second multi-channel parameters and second processed channels. The channel encoder is configured to encode channels resulting from an iteration processing to obtain encoded channels. The output interface is configured to generate an encoded multi-channel signal including the encoded channels and the first and second multi-channel parameters.

Apparatus and method for encoding or decoding a multi-channel signal

An apparatus for decoding an encoded multichannel signal of a current frame to obtain three or more current audio output channels is provided. A multichannel processor is adapted to select two decoded channels from three or more decoded channels depending on first multichannel parameters. Moreover, the multichannel processor is adapted to generate a first group of two or more processed channels based on the selected channels. A noise filling module is adapted to identify for at least one of the selected channels, one or more frequency bands, within which all spectral lines are quantized to zero, and to generate a mixing channel using, depending on side information, a proper subset of three or more previous audio output channels that have been decoded, and to fill the spectral lines of frequency bands, within which all spectral lines are quantized to zero, with noise generated using spectral lines of the mixing channel.

Apparatus and method for stereo filling in multichannel coding

An apparatus for generating a plurality of audio channels for a speaker setup, comprises a processor repeating an energy distribution from a speaker not contained in the speaker setup to the speakers in the speaker setup to acquire a downmix information for a downmix to the speaker setup; and a renderer for generating the plurality of audio channels using the downmix information.

Apparatus and method for generating a plurality of audio channels

An apparatus for generating a plurality of audio channels for a first speaker setup is characterized by an imaginary speaker determiner, an energy distribution calculator, a processor and a renderer. The imaginary speaker determiner is configured to determine a position of an imaginary speaker not contained in the first speaker setup to obtain a second speaker setup containing the imaginary speaker. The energy distribution calculator is configured to calculate an energy distribution from the imaginary speaker to the other speakers in the second speaker setup. The processor is configured to repeat the energy distribution to obtain a downmix information for a downmix from the second speaker setup to the first speaker setup. The renderer is configured to generate the plurality of audio channels using the downmix information.

A decoder for decoding a plurality of spectral-domain audio samples is provided. The decoder includes a first decoding module for generating a first group and a second group of time-domain intermediate audio samples from the spectral-domain audio samples. Moreover, the decoder includes an overlap-adder for overlap-adding the first group of time-domain intermediate audio samples with an overlap of more than 5% and at most 50% with the second group of time-domain intermediate audio samples. Furthermore, the decoder includes a second decoding module for generating a third group and a fourth group of time-domain intermediate audio samples from the spectral-domain audio samples. Moreover, the decoder includes an output interface.

Encoder, decoder and methods for signal-adaptive switching of the overlap ratio in audio transform coding

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Zirndorf, Germany

Florian Schuh