Dolby International Ab

Dolby Laboratories Licensing Corporation

Jens Popp

Heiko Purnhagen

Karl Jonas Roeden

Kristofer Kjoerling

Holger Hoerich

Alexander Stahlmann

Alexander Groeschel

Martin Wolters

Michael C Ward

Jeffrey Charles Riedmiller

Kristofer Kjörling

Christof Fersch

Karsten Linzmeier

Tobias Friedrich

Claus-Christian Spenger

Malte Schmidt

Marc Roessler

Celine Merpillat

Kristopher Kjoerling

Tobias Mueller

An audio processing system () accepts an audio bitstream having one of a plurality of predefined audio frame rates. The system comprises a front-end component (), which receives a variable number of quantized spectral components, corresponding to one audio frame in any of the predefined audio frame rates, and performs an inverse quantization according to predetermined, frequency-dependent quantization levels. The front-end component may be agnostic of the audio frame rate. The audio processing system further comprises a frequency-domain processing stage () and a sample rate converter (), which provide a reconstructed audio signal sampled at a target sampling frequency independent of the audio frame rate. By its frame-rate adaptability, the system can be configured to operate frame-synchronously in parallel with a video processing system that accepts plural video frame rates.

Method, apparatus and systems for audio decoding and encoding

An audio bitstream is decoded into audio objects and audio metadata for the audio objects. The audio objects include a specific audio object. The audio metadata specifies frame-level gains that include a first gain and a second gain respectively for a first audio frame and a second audio frame. It is determined, based on the first and second gains, whether sub-frame gains are to be generated for the specific audio object. If so, a ramp length is determined for a ramp used to generate the sub-frame gains for the specific audio object. The ramp of the ramp length is used to generate the sub-frame gains for the specific audio object. A sound field represented by the audio objects with the sub-frame gains is rendered by audio speakers.

Main-associated audio experience with efficient ducking gain application

Audio decoder utilizing sample rate conversion for frame synchronization

The present document relates to time-alignment of encoded data of an audio encoder with associated metadata, such as spectral band replication (SBR) metadata. An audio decoder configured to determine a reconstructed frame of an audio signal from an access unit of a received data stream is described. The access unit comprises waveform data and metadata, wherein the waveform data and the metadata are associated with the same reconstructed frame of the audio signal. The audio decoder comprises a waveform processing path configured to generate a plurality of waveform subband signals from the waveform data, and a metadata processing path configured to generate decoded metadata from the metadata.

Time-alignment of QMF based processing data

The present document relates to time-alignment of encoded data of an audio encoder with associated metadata, such as spectral band replication (SBR) metadata. An audio decoder () configured to determine a reconstructed frame of an audio signal () from an access unit () of a received data stream is described. The access unit () comprises waveform data () and metadata (), wherein the waveform data () and the metadata () are associated with the same reconstructed frame of the audio signal (). The audio decoder () comprises a waveform processing path () configured to generate a plurality of waveform subband signals () from the waveform data (), and a metadata processing path () configured to generate decoded metadata () from the metadata ().

The present document relates to the determination of a 200 bitrate related to an encoded bitstream, and describes a method for determining an estimate of a bitrate of a bitstream comprising a sequence of frames comprising a varying number of bitsand corresponding to excerpts of an audio and/or video signal. At least two frames of the sequence of frames comprise a parameter indicative of a processing delay for the corresponding frame. The method comprises determining: a total number of bits for a subsequence of frames from the bitstream; a corrected number 201 of frames based on a number of frames comprised within the subsequence and the parameters of at least two frames of the subsequence; and a lower bitrate bound and an upper bitrate bound of the bitrate based on the total number of bits, the corrected number of frames and a frame rate of the bitstream.

Method for bitrate signaling and bitstream format enabling such method

The present document relates to the design of anti-aliasing and/or anti-imaging filters for resamplers using rational resampling factors. In particular, the present document relates to a method for implementing such anti-aliasing and/or anti-imaging filters with reduced computational complexity. In addition, the present document relates to further aspects of an audio encoding and decoding system, such as the phase relation between the channels of a multi-channel audio signal and/or the structure of the bitstream of an encoded audio signal.

System aspects of an audio codec

The present document relates to the field of encoding and decoding of audio. In particular, the present document relates to encoding and decoding of an audio scene comprising audio objects. A method () for encoding metadata relating to a plurality of audio objects () of an audio scene () is described. The metadata comprises a first set () of metadata and a second set () of metadata. The first and second sets () of metadata comprise one or more data elements which are indicative of a property of an audio object () from the plurality of audio objects () and/or of a downmix signal () derived from the plurality of audio objects (). The method () comprises identifying () a redundant data element which is common to the first and second sets () of metadata. Furthermore, the method comprises encoding () the redundant data element of the first set () of metadata by referring to a redundant data element of a set () of metadata external for the first set () of metadata.

Exploiting metadata redundancy in immersive audio metadata

Audio decoder utilizing sample rate conversion for audio and video frame synchronization

Growing community of inventors

Nuremberg, Germany

Jens Popp