Skype Limited

Microsoft Technology Licensing, LLC

Soren Vang Andersen

Mattias Nilsson

Renat Vafin

Christoffer Asgaard Rödbro

Mark Alastair Gillett

Lazar Bivolarsky

Andrei Jefremov

Koen Bernard Vos

Mingyu Chen

Ahti Heinla

Jonas Lindblom

Magnus Hiie

Silver Keskkula

Soren Skak Jensen

Stefan Strommer

Silver Keskküla

Christoffer Rödbro

Correction data units for data packets of a data stream are generated. A correction data unit is based on a set of the data packets of the stream. The stream is transmitted over a communication channel. A performance measure to be optimized is selected, which relates to the recovery of lost data packets of the stream. To optimize the performance measure, a plurality of correction data vectors are determined, and a plurality of a plurality of non-recovery probabilities, corresponding to the correction data vectors, are initialized. One or more of the correction data vectors are selected that contribute towards a non-recovery probability of an original data packet. The non-recovery probability associated with the original data packet is then minimized based on the selected one or more correction data vectors. The selected one or more correction data vectors are then used to determine which of the original data packets or data correction units to transmit.

Computation of forward error correction data units using loss vector probabilities

Methods and systems for selecting access networks are disclosed. In one aspects, a mobile terminal includes one or more transceivers configured to selectively connect to the plurality of wireless access networks, and hardware processing circuitry configured to perform operations including obtaining, via one of the plurality of wireless access networks, motion information for one or more other access networks of the plurality of access networks, the motion information indicating motion of one or more connection points; and controlling activation of the one or more transceivers to scan for availability of one or more of the other access networks in dependence on the motion information of the other access networks, wherein the scanning for availability comprises powering up at least one of the one or more transceivers to determine which access networks are present within a proximity of the mobile terminal.

Determining suitability of an access network

Methods and systems for selective scanning of connection points are disclosed. In one aspect, a non-transitory computer readable storage medium comprises instructions that configure hardware processing circuitry to perform operations. The operations include determining a location of a mobile terminal, storing network capability information associated with one or more connection points within a defined proximity of the location of the mobile terminal, comparing network capabilities of an existing network connection of the mobile terminal to the stored network capabilities associated with the one or more connection points, selectively scanning for the one or more connection points based on the comparison to determine whether the one or more connection points are available; and switching from the existing network connection to one of the one or more connection points based on the availability of the one or more connection points.

Mobile device information sharing

A method of regenerating wideband speech from narrowband speech, the method comprising: receiving samples of a narrowband speech signal having a first range of frequencies; identifying, based on a characteristic of the narrowband speech signal, frequencies in the first range of frequencies to translate into a target band of a regenerated speech signal; modulating the identified frequencies in the first range of frequencies of the received samples of the narrowband speech signal with a modulation signal, the modulation signal having a modulating frequency adapted to upshift the identified frequencies in the first range of frequencies into the target band; filtering the modulated samples, using a target band filter, to form the regenerated speech signal in the target band; and combining the narrowband speech signal with the regenerated speech signal to produce a new wideband speech signal.

Regeneration of wideband speech

Methods and systems for use in a wireless communications system are disclosed. In some aspects, a method includes determining motion information for a first connection point of one of the plurality of wireless access networks, the motion information indicating motion of the first connection point, causing to be stored, in a data repository, the determined motion information, the database accessible by device via one of the plurality of wireless access networks, obtaining second motion information for a second connection point for a second of the plurality of wireless access networks from the data repository, the second motion information indicating motion of the second connection point; and determining whether to connect to the second connection point based on the second motion information.

Methods and systems for selecting access networks are disclosed. In one aspect, a method includes receiving, from a first plurality of mobile terminals, a corresponding plurality of motion information for a corresponding plurality of connection points for one or more corresponding wireless access networks, storing the plurality of motion information in a data repository, receiving from a second plurality of mobile terminals non-overlapping with the first plurality of mobile terminals, requests for different subsets of the plurality of motion information, reading the requested motion information from the data repository in response to the requests, and transmitting the requested motion information to the requesting mobile terminals.

Correction data units for data packets of a data stream are generated. A correction data unit is based on a set of the data packets of the stream. The stream is transmitted over a lossy communication channel. A performance measure to be optimized is selected, which relates to the recovery of lost data packets of the stream. A coding requirement is determined. For the generation of the correction data units, it is determined, within the constraints of the coding requirement and based on previously generated correction data units, which of the data packets in the stream to include in the set on which the generation of the correction data unit is to be based to thereby optimize the selected performance measure. A generated correction data unit is generated based on a respective set of the data packets of the stream. The generated correction data units are included in the stream.

Correction data

A mobile terminal for use in a communication system comprising a first, packet-based network and a plurality of wireless access networks providing access to the first network. The mobile terminal comprises: one or more transceivers for connecting to the wireless access networks; and processing apparatus coupled to the one or more transceivers, operable to communicate with the first network by forming connections with the access networks using the one or more transceivers. The processing apparatus is configured to access a database recording motion information relating to motion of connection points of the wireless access networks; and the processing apparatus is further configured to determine one of the wireless access networks for use in accessing the first network, in dependence on the motion information accessed from the database relating to one or more of the wireless access networks.

A method of performing a rate-distortion optimization process comprising selecting a preferred encoding mode by optimizing a function comprising an estimate of distortion for a target image portion and a measure of bit rate required to encode that portion. The estimate of distortion is based on source coding distortion and an estimate of error propagation distortion due to loss. The method further comprises transmitting the same encoded version of the video stream from the transmitting terminal to each of a plurality of receiving terminals over respective lossy channels, using the same rate-distortion optimization process in relation to each of the plurality of receiving terminals, making the same encoding mode selection per target image portion based on the same optimization of said function. The estimate of error propagation distortion comprises an aggregate estimate of error propagation distortion that would be experienced due to possible loss over the plurality of channels.

Video coding

An encoder stage, and corresponding encoded bitstream and decoder. The encoder stage comprises: a variable length encoder for encoding an input signal; and a counter configured to dynamically detect an observed frequency at which different symbols are found to occur within each of a plurality of predetermined portions of the input signal, prior to the symbols of each respective portion being encoded by the variable length encoder. The variable length encoder is configured to encode the symbols of each portion using variable length coding performed in dependence on the observed frequencies detected within the respective portion of the input signal, to generate an encoded bitstream comprising the encoded symbols along with an additional element indicating information regarding the observed frequencies detected for each portion, and to output the encoded bitstream to at least one of a storage medium and a transmission medium for supply to a decoder.

Entropy encoding based on observed frequency

In an embodiment, a method of controlling transmission of data from a wireless device to a receiver connected via a communication channel includes an application executing on the wireless device providing an estimate of end-to-end bandwidth of the communication channel; supplying to the application from wireless access circuitry in the wireless device at least on communication-related parameter and modifying in the application the estimate of end-to-end bandwidth using the at least one communication-related parameter.

Controlling transmission of data

A mobile terminal comprising: a positioning module arranged to determine a geographical location of the mobile terminal; a local transceiver for connecting to local wireless access networks; and processing apparatus for communicating with a first, packet-based network by forming connections with the wireless local area networks using the local transceiver. The processing apparatus is configured to determine measures of connection quality experienced by the mobile terminal on ones of the connections, and to record the determined measures in a database associating measures of connection quality with geographical locations. The processing apparatus is further configured to control activation of the local transceiver to scan for subsequent availability of one or more of the wireless local area networks, in dependence on one or more of the measures of connection quality and associated geographical locations in the database relative to the geographical location of the mobile terminal as determined by the positioning module.

Determining network availability based on geographical location

A method of selecting reference blocks for intra or inter prediction coding of a current block of a video signal. Each reference blocks is selected by: (i) determining a group of candidate blocks comprising at least some candidate blocks other than immediately adjacent spatial neighbors of the current block; and (ii) selecting one of the candidate blocks as the reference block based on a second metric, different from the first metric, the second metric relating to a number of bits that would be required in the encoded bitstream to encode both the residual block and the side information identifying the respective reference block.

Compression for frames of a video signal using selected candidate blocks

The present invention provides a technique for performing one or more aspects of video coding such as quantization, intra prediction coding or inter prediction coding in dependence on a perceptual model taking into account human sensitivity to data in the video signal. The perceptual model may relate to spatial frequency, temporal frequency, contrast sensitivity, color sensitivity, a structural metric, and/or one or more parameters affecting perception such as motion in the video, the distance of a recipient user from the screen, and the size, aspect ratio or resolution of the screen of the recipient terminal.

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Esch-sur-Alzette, Luxembourg

Soren Vang Andersen