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 packet scheduler reduces or "compresses" the packet transmission delay jitter or delay range where packets experience little or no scheduling delay before transmission. As a result, the number of packets that experience little or no delay is reduced. A preferred example way of compressing the packet transmission delay jitter is to reduce the transmission priority of low delay packets. Compressing the delay jitter is particularly desirable for services like VoIP that require low packet transmission delay jitter.
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 present invention relates to methods for improving speech quality in e.g. an IP-telephony system. The invention reduces audio artefacts being due to overrun or underrun in a playout buffer caused by the sampling rates at a sending and receiving side not being at the same rate. The inventive solution modifies an LPC-residual on a sample-by-sample basis. The LPC-residual block comprising N samples is converted to a block comprising N+1 or N-1 samples. A sample rate controller 400 decides whether samples should be added to or removed from the LPC-residual. The exact position where to add respective remove samples is either chosen arbitrarily or found by searching for low energy segments in the LPC-residual. A speech synthesiser module 430 then reproduces the speech. By using the proposed sample rate conversion method the playout buffer 440 can be continuously controlled. Furthermore, since the method works on a sample-by-sample basis the buffer can be kept to a minimum and hence no extra delay is introduced.
Abstract:
The present invention sends multiple versions of a multimedia packet to the base station, and, based on the radio channel and traffic characteristics, an appropriate version of the multimedia packet is selected to send to the mobile station at a given time. In this way, source transmission is improved to instantaneous conditions. The steps of the present invention are performed in conjunction with RTP used for multimedia transmission over internet protocol (IP) networks. In a first embodiment, the multiple versions are sent to the base station in the same RTP packet, and the base station strips out the extraneous versions. In a second embodiment, the base station receives multiple RTP packets having identical information in the packet header in many fields, and selects an appropriate one among these for transmission to the mobile station, discarding the rest.
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:
Método, llevado a cabo por un primer nodo (110), para gestionar el procesado o tratamiento de un flujo continuo de audio, en donde el flujo continuo de audio es recibible de un segundo nodo (120), en donde el método comprende: enviar (204), al segundo nodo (120), información referente a por lo menos una preferencia relativa a características acústicas del flujo continuo de audio, en donde la por lo menos una preferencia relativa a características acústicas se refiere a uno o más de: un nivel de supresión de ruido en el flujo continuo de audio, un nivel de voz en el flujo continuo de audio, y un ancho de banda del flujo continuo de audio, en donde la por lo menos una preferencia relativa a características acústicas es determinada por un usuario previo o actual del primer nodo (110), o en donde la por lo menos una preferencia relativa a características acústicas es determinada por un operador de un sistema (100) de radiocomunicaciones que comprende el primer y el segundo nodos (110, 120); y recibir (210) el flujo continuo de audio del segundo nodo (120), en donde el flujo continuo de audio ha sido tratado, por el segundo nodo (120), como respuesta a la información referente a la por lo menos una preferencia relativa a las características acústicas del flujo continuo de audio.
Abstract:
A packet scheduler reduces or "compresses" the packet transmission delay jitter or delay range where packets experience little or no scheduling delay before transmission. As a result, the number of packets that experience little or no delay is reduced. A preferred example way of compressing the packet transmission delay jitter is to reduce the transmission priority of low delay packets. Compressing the delay jitter is particularly desirable for services like VoIP that require low packet transmission delay jitter.