Telefonaktiebolaget Lm Ericsson (publ)

Fredrik Klas Jansson

Erik Norvell

Tomas Jansson Toftgård

Karl Hellwig

Erlendur Karlsson

Jim Sundqvist

Bo Hagerman

Stefan Bruhn

Anisse Taleb

Ingemar Johansson

Tomas Frankkila

Karim Jamal

Daniel Enström

Erik Ekudden

Stefan Håkansson

Jonas Lundberg

Thomas &Ouml;stman

Johan Nystr&ouml;m

Yang Zuo

Rolf A Bergstrom

Tor Bj&ouml;rn Minde

Karl T Wigren

Charles Kinuthia

Moo Young Kim

A method, system, and computer program to encode and decode a channel coherence parameter applied on a frequency band basis, where the coherence parameters of each frequency band form a coherence vector. The coherence vector is encoded and decoded using a predictive scheme followed by a variable bit rate entropy coding.

Truncateable predictive coding

A method for generating comfort noise is provided. The method includes providing a first set of background noise parameters Nfor at least one audio signal in a first spatial audio coding mode and a second set of background noise parameters Nfor the at least one audio signal in a second spatial audio coding mode. The first spatial audio coding mode is used for active segments; the second spatial audio coding mode is used for inactive segments. The method further includes adapting the first set of background noise parameters Nto the second spatial audio coding mode, thereby providing a first set of adapted background noise parameters {circumflex over (N)}. The method further includes generating comfort noise parameters by combining {circumflex over (N)}and Nover a transition period. The method further includes generating comfort noise based on the comfort noise parameters.

Comfort noise generation for multi-mode spatial audio coding

A method for generation of comfort noise for at least two audio channels. The method comprises determining a spatial coherence between audio signals on the respective audio channels, wherein at least one spatial coherence value per frame and frequency band is determined to form a vector of spatial coherence values. A vector of predicted spatial coherence values is formed by a weighted combination of a first coherence prediction and a second coherence prediction that are combined using a weight factor α. The method comprises signaling information about the weight factor α to the receiving node, for enabling the generation of the comfort noise for the at least two audio channels at the receiving node.

Support for generation of comfort noise, and generation of comfort noise

A method for generating a comfort noise (CN) parameter is provided. The method includes receiving an audio input; detecting, with a Voice Activity Detector (VAD), a current inactive segment in the audio input; as a result of detecting, with the VAD, the current inactive segment in the audio input, calculating a CN parameter CN; and providing the CN parameter CNto a decoder. The CN parameter CNis calculated based at least in part on the current inactive segment and a previous inactive segment.

Adaptive comfort noise parameter determination

A method and a transmitting node for supporting generation of comfort noise for at least two audio channels at a receiving node. The method is performed by a transmitting node. The method comprises determining spectral characteristics of audio signals on at least two input audio channels and determining a spatial coherence between the audio signals. The spatial coherence is associated with perceptual importance measures. A compressed representation of the spatial coherence is determined per frequency band by weighting the spatial coherence within each frequency band according to the perceptual importance measures. Information about the spectral characteristics and the compressed representation of the spatial coherence per frequency band is signaled to the receiving node for enabling the generation of the comfort noise at the receiving node.

Support for generation of comfort noise

A method for generation of comfort noise for at least two audio channels. The method comprises determining a spatial coherence between audio signals on the respective audio channels, wherein at least one spatial coherence value per frame and frequency band is determined to form a vector of spatial coherence values. A vector of predicted spatial coherence values is formed by a weighted combination of a first coherence prediction and a second coherence prediction that are combined using a weight factor a. The method comprises signaling information about the weight factor a to the receiving node, for enabling the generation of the comfort noise for the at least two audio channels at the receiving node.

It is presented a method for managing a jitter buffer depth for receiving real-time communication. The method is performed in a receiver and comprises the steps of: determining an adaptive bitrate state of the receiver when a current capacity of a communication channel for receiving the real-time communication is below a maximum bitrate for receiving the real-time communication; and increasing a depth of a jitter buffer for receiving the real-time communication when the adaptive bitrate state is determined.

Managing a jitter buffer size

There is provided determination of a bit rate request (BRR) for a multimedia encoder of an electronic device. First bit rate information is received from a receiver of multimedia content. The multimedia content is generated by the multimedia encoder and transmitted by the electronic device on a transmission link of the electronic device to the receiver. The first bit rate information is related to the transmission link. Second bit rate information relating to a reception link of the electronic device is acquired. A set of properties of the transmission link and the reception link is determined. A combined BRR is determined for the multimedia encoder as a function of the first bit rate information and the second bit rate information, wherein the function depends on the set of properties. The combined BRR is provided to the multimedia encoder.

Determination of bit rate request

A method of controlling an adaptable jitter buffer in accordance with the present invention detects a context description of data handled by the adaptable jitter buffer. Thereafter it is determined whether the detected context description is equal to a predetermined context description. If not, jitter buffer adaptation proceeds as normal. Otherwise it is determined whether the current target buffer depth is too low for the detected context description. If not, the target buffer depth is frozen to the current value. Otherwise it is increased and frozen at a higher value that is compatible with the detected context description.

Jitter buffer control

A method for controlling a jitter buffer and a communication apparatus implementing the method and functioning as a first node of a communication system, wherein the jitter butter is adapted to buffer a stream of blocks of compressed speech information generated in a second node in the communication system, transmitted to and received in the first node. Blocks of compressed speech information in said stream of blocks are selected () according to a predetermined rule based on the current buffering delay of the jitter buffer and at least one characteristic of said blocks of compressed speech information. Predetermined actions aiming at reducing buffering delay in the jitter butter are applied () to the selected blocks.

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Sundbyberg, Sweden

Fredrik Klas Jansson