Abstract:
A method of encoding multi-channel audio signals comprises generating of a first output signal (x' mono ), being encoding (38) parameters representing a main signal (x mono ). The main signal (x mono ) is a first linear combination (34) of signals (16A,16B) of at least a first and a second channel. The method further comprises generating (30) of a second output signal (p side ), being encoding parameters representing a side signal (x side ). The side signal (x side ) is a second linear combination (36) of signals (16A,16B) of at least the first and the second channel within an encoding frame. The method is characterised in that the generating of the second output signal further comprises scaling of the side signal (x side ) to an energy contour of the main signal (x mono ). A method of decoding is also presented as well as an encoder, a decoder and audio system, all according to the same basic idea.
Abstract:
In order to efficiently handle the switch between user media and announcement media, a basic step (Sl) is to first determine a configuration of the user media. Next, a configuration of the announcement media to be presented is determined (S2) based on the determined user media configuration. Subsequently, the announcement media is configured (S3) according to the announcement media configuration, and the configured announcement media is finally sent (S4) to the intended user. In this way, the overall appearance or sound of the announcement will be virtually the same as or at least similar to the overall appearance or sound of the user media, preferably without distortions. This allows the user to perceive the announcement as clearly as possible.
Abstract:
A method and a communication station (5) for determining a packet format of a data packet based on at least one compressed header information field. A header packet format of a data packet is determined based on the determined packet format of a partially or completely compressed header information part. The station may also determine a codec rate (10) based on the result of a previously performed compression of at least one header information field. In one embodiment, internal cross-layer signaling from a header generator module (6) to a payload generator module (7) in the communication station is used for signaling information associated with determining the header packet format of the data packet. The method reduces bandwidth fluctuations associated with services such as text messaging, audio, or audiovisual services; lowers the delay variations and the erasure rates for application media streams; and provides for faster set-up of sessions.
Abstract:
A receiver (100) includes a detector (140) for detecting a change in source of incoming media during an on-going communication session, and means to provide a reset signal in order to reset decoder states of a decoder (120) in response to such a detected change before decoding new incoming media. In this way, a state mismatch can be avoided without the need for several active decoder instances in the receiver (100), leading to substantial savings with respect to overall complexity, memory usage and power consumption. This also means that media distortions can be eliminated or at least reduced when the decoded media is finally rendered by a player (130).
Abstract:
The quality of comfort noise generated by a speech decoder (93) during non-speech periods is improved by modifying (30, 75) comfort noise parameter values (33) normally used to generate the comfort noise. The comfort noise parameter values are modified in response to variability information (43) associated with a background noise parameter. The modified comfort noise parameter values (35) are then used to generate the comfort noise.
Abstract:
In a method of improved media frame transmission in a communication network. Initially a plurality of "original" or regular media frames are provided for transmission. According to the invention, robust representations of the provided regular media frames are generated and stored locally. Subsequently, one or more of the regular media frames is/ are transmitted. The invention detects an indication of a loss of a transmitted media frame, and the idea is to transmit, in response to a detected frame loss, a stored robust representation of the lost media frame and/ or a stored robust representation of a subsequent, not yet transmitted, media frame to increase the media quality.
Abstract:
A method and apparatus for acquiring time synchronization, as well as a channel estimate and a noise estimate for a received signal are described. First, a burst of data which includes a training sequence is received. Then, groups of received training sequence measurements are created. For each of these groups, a set of linear equations is set up. Next, methods according to the present invention determine the least square estimate by solving the matrix equation H = (A A) A L for each of the groups. This least square estimate is performed in several steps which reduce the number of calculations to be performed. The term A A is the same for each group and can be computed once prior to computing the least square estimates. The A L terms are calculated separately for each group. In the process of calculating the A L term for each group, the A L term calculated for the previous group can be reused to reduce the total number of calculations. Once the A A and A L terms are calculated, then the least square estimate for each group is determined. The least square estimate is then used to determine a noise estimate for each group. Again, mechanisms for reuse of certain calculations associated with the determination of the noise estimate that reduces the computational complexity associated therewith. Once the noise estimate is calculated for each group, the method determines which of the groups has the lowest valued noise estimate. That group, according to one exemplary embodiment, is chosen as the synchronization group. As an alternative, the group which has the greatest estimated signal-to-noise ratio can be selected as the synchronization group in this step. The least square estimate of the synchronization group is then identified as the channel estimate.
Abstract:
Un método para controlar un receptor de una comunicación mediante unidades de datos desde una fuente dedatos, estando el citado receptor asociado con un primer terminal de una red de comunicación mediante unidadesde datos que proporciona al primer terminal un servicio de transporte caracterizado por un conjunto de valoresasociados con respectivos parámetros de calidad de servicio, comprendiendo los citados parámetros de calidad deservicio un primer parámetro de capacidad de transmisión mínima, estando la citada fuente de datos asociada conun segundo terminal, comprendiendo el citado método:- determinar (S40), por parte del receptor, si una unidad de datos recibida contiene una marca de indicaciónde congestión,- si se detecta la citada marca de indicación de congestión, enviar (S42) desde el receptor a la citada fuentede datos un mensaje para ajustar una tasa de transmisión de datos de la citada fuente de datos, indicando elcitado mensaje como límite superior para la citada tasa de transmisión de datos un valor correspondiente a unvalor asociado con el primer parámetro de capacidad de transmisión mínima para el citado servicio detransporte proporcionado al citado primer terminal asociado con el citado receptor.
Abstract:
A network processing node (e.g., MGW, MRFP) and method are described herein that can: (1) receive packets on a first heterogeneous link (e.g., wireless link); (2) manipulate the received packets based on known characteristics about a second heterogeneous link (e.g., "Internet" link); and (3) send the manipulated packets on the second heterogeneous link (e.g., "Internet" link). For example, the network processing node can manipulate the received packets by adding redundancy, removing redundancy, frame aggregating (re-packetizing), recovering lost packets and/or re-transmitting packets.
Abstract:
In packet communications that employ header compression/decompression, the computational complexity of checksum generation can be reduced by re-using static checksum information associated with header bits (S) that do not change from header to header. The static checksum information can be used together with information about header bits (T) that do change from header to header, in order to generate a desired checksum (CS). The checksum can then be used to verify a reconstructed header (17) produced from a compressed header by a header decompressor.