Fraunhofer-gesellschaft Zur Foerderung Der Angewandten Forschung E.v.

Dolby International Ab

Christian Helmrich

Sascha Disch

Bernd Edler

Goran Markovic

Ralf Geiger

Johannes Hilpert

Frederik Nagel

Konstantin Schmidt

Ralph Sperschneider

Guillaume Fuchs

Nikolaus Rettelbach

Christian Neukam

Sascha Dick

Jérémie Lecomte

Michael Schnabel

Stefan Bayer

Andreas Hoelzer

Matthias Neusinger

Balaji Nagendran Thoshkahna

Markus Multrus

Emmanuel Ravelli

Martin Dietz

Christian Ertel

Markus Schnell

Stefan Doehla

Manuel Jander

Maria Luis Valero

Max Neuendorf

Thomas Wiegand

Detlev Marpe

Heiko Schwarz

Achim Kuntz

Julien Robilliard

Benjamin Schubert

Stefan Reuschl

Dominik Zorn

Jeremie Lecomte

Benjamin Bross

Tom Baeckstroem

Bernhard Grill

Andreas Holzer

Tom Backstrom

Marc Gayer

Andreas Niedermeier

Eleni Fotopoulou

Florin Ghido

Wolfgang Jaegers

Michael Fischer

Florian Schuh

Sebastian Bosse

Richard Fueg

Paul Keydel

Janine Sukowski

Tung Nguyen

Mischa Siekmann

Phan Hoang Tung Nguyen

Adam Wieckowski

Yoshikazu Yokotani

Arthur Tritthart

Markovic Goran

Julien Robillard

Stefan Dohla

Lars Villemoes

Heiko Purnhagen

Juergen Herre

Pontus Carlsson

Stephan Wilde

Johannes Fischer

Vesa Ruoppila

Tobias Schwegler

Johannes Erfurt

Soeren Becker

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 audio decoder for providing at least four audio channel signals on the basis of an encoded representation is configured to provide a first residual signal and a second residual signal on the basis of a jointly encoded representation of the first residual signal and of the second residual signal using a multi-channel decoding. The audio decoder is configured to provide a first audio channel signal and a second audio channel signal on the basis of a first downmix signal and the first residual signal using a residual-signal-assisted multi-channel decoding. The audio decoder is configured to provide a third audio channel signal and a fourth audio channel signal on the basis of a second downmix signal and the second residual signal using a residual-signal-assisted multi-channel decoding. An audio encoder is based on corresponding considerations.

Audio encoder, audio decoder, methods and computer program using jointly encoded residual signals

A device and method for manipulating an audio signal includes a windower for generating a plurality of consecutive blocks of audio samples, the plurality of consecutive blocks including at least one padded block of audio samples, the padded block having padded values and audio signal values, a first converter for converting the padded block into a spectral representation having spectral values, a phase modifier for modifying phases of the spectral values to obtain a modified spectral representation and a second converter for converting the modified spectral representation into a modified time domain audio signal.

Device and method for manipulating an audio signal

An apparatus processing an encoded signal to acquire first and second frames comprising spectral values and an aliasing portion; applying a transform to the first frame using a first window function to acquire a first block of samples, applying another transform to a first portion of the second frame using a second window function, and applying another one or more transforms to a second portion of the second frame using one or more third window functions to acquire a second block of samples; and post-processing the second block of samples using a folding-out operation to acquire a post-processed second block of samples comprising a portion of the second block of samples overlapping with the first block of samples in a multi-overlap region, windowing the post-processed second block of samples using an auxiliary window function, and overlap-adding a windowed post-processed second block of samples and the first block of samples.

Apparatus and method for decoding an encoded audio or image signal using an auxiliary window function

In multichannel audio coding, an improved coding efficiency is achieved by the following measure: the noise filling of zero-quantized scale factor bands is performed using noise filling sources other than artificially generated noise or spectral replica. In particular, the coding efficiency in multichannel audio coding may be rendered more efficient by performing the noise filling based on noise generated using spectral lines from a previous frame of, or a different channel of the current frame of, the multichannel audio signal.

Noise filling in multichannel audio coding

A schematic block diagram of a decoder for decoding an encoded audio signal is shown. The decoder includes an adaptive spectrum-time converter and an overlap-add-processor. The adaptive spectrum-time converter converts successive blocks of spectral values into successive blocks of time values, e.g. via a frequency-to-time transform. Furthermore, the adaptive spectrum-time converter receives a control information and switches, in response to the control information, between transform kernels of a first group of transform kernels including one or more transform kernels having different symmetries at sides of a kernel, and a second group of transform kernels including one or more transform kernels having the same symmetries at sides of a transform kernel. Moreover, the overlap-add-processor overlaps and adds the successive blocks of time values to obtain decoded audio values, which may be a decoded audio signal.

Decoder for decoding an encoded audio signal and encoder for encoding an audio signal

Decoder for decoding a picture from a data stream, configured to check whether a plurality of coding parameters, which are contained in the data stream, relate to a predetermined portion of the picture and control a prediction residual transform mode and a quantization accuracy with respect to the predetermined portion, are indicative of a coding parameter setting corresponding to a lossless prediction residual coding. Responsive to the plurality of coding parameters being indicative of the coding parameter setting corresponding to the lossless prediction residual coding, the decoder is configured to set one or more predetermined coding options relating to one or more tools of the decoder for processing a prediction residual corrected predictive reconstruction with respect to the predetermined portion so that the one or more tools are disabled with respect to the predetermined portion.

Encoder, decoder, methods and computer programs for an improved lossless compression

An apparatus for processing an audio signal having associated therewith a pitch lag information and a gain information, includes a domain converter for converting a first domain representation of the audio signal into a second domain representation of the audio signal; and a harmonic post-filter for filtering the second domain representation of the audio signal, wherein the post-filter is based on a transfer function including a numerator and a denominator, wherein the numerator includes a gain value indicated by the gain information, and wherein the denominator includes an integer part of a pitch lag indicated by the pitch lag information and a multi-tap filter depending on a fractional part of the pitch lag.

Apparatus and method for processing an audio signal using a harmonic post-filter

An apparatus for generating a decoded two-channel signal, comprising: a parametric decoder for providing parametric data for a second set of second spectral portions and a two-channel identification identifying for a second spectral portion of the second set of second spectral portions either a first two-channel representation for the second spectral portion of the second set of second spectral portions or a second two-channel representation for the second spectral portion of the second set of second spectral portions, the second two-channel representation being different from the first two-channel representation; and a frequency regenerator for regenerating the second spectral portion of the second set of second spectral portions depending on a first spectral portion of a first set of first spectral portions, the parametric data for the second spectral portion of the second set of second spectral portions and the two-channel identification for the second spectral portion of the second set of second spectral portions to acquire a regenerated second spectral portion of the second set of second spectral portions.

Audio encoder, audio decoder and related methods using two-channel processing within an intelligent gap filling framework

An apparatus for determining visual activity information for a predetermined picture block of a video sequence including a plurality of video frames, the plurality of video frames including a current video frame and one or more timely-preceding video frames, wherein the one or more timely-preceding video frames precede the current video frame in time, is provided. The apparatus is configured to receive the predetermined picture block of each of the one or more timely-preceding video frames and the predetermined picture block of the current video frame. Moreover, the apparatus is configured to determine the visual activity information depending on the predetermined picture block of the current video frame and depending on the predetermined picture block of each of the one or more timely-preceding video frames and depending on a temporal high-pass filter.

Apparatus and method for improved video quality assessment

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Erlangen, Germany

Christian Helmrich