The Xarxa Audiovisual Local (XAL) makes the most of the new IP network with an eye on a gradual migration to HD

In recent years, the Now, it has its sights set on a full migration to high definition.

The Xarxa Audiovisual Local (SOLUTION) It was established in 2012 by the Council of Barcelona to manage support for local Catalan audiovisuals, responding to their needs and contributing to the revitalization of the sector. These objectives are developed through the brand Local Communication Network, a multimedia platform of content and services available to local media in Catalonia (television, radio and online media).

The main service that the An action criterion that aims, on the one hand, to increase the visibility of local audiovisual content by distributing it to all participating media and thus expanding the potential audience; and, on the other, economically stimulate the sector.

The XAL manages informative and sports content, as well as informative and entertainment content.. En cuanto a los contenidos informativos y deportivos, hace hincapié en la información local y se elabora a partir de la coordinación periodística entre los servicios informativos de la XAL y las redacciones de los medios adheridos. Esta tarea conjunta la centraliza el servicio de contenidos informativos Xarxa Mèdia, en la que ambas partes comparten diariamente tanto previsiones de cobertura informativa como piezas de actualidad.

Respecto a los contenidos divulgativos y de entretenimiento, conforman un catálogo que se renueva periódicamente coincidiendo con el inicio de la temporada radiofónica (anual) y televisiva (trimestral). Este catálogo va adquiriendo progresivamente una dimensión multimedia con la incorporación de programas con un doble formato (radiofónico y televisivo). La Xarxa pone a disposición de los medios adheridos diversas herramientas para distribuir y compartir contenidos.

Paulatinamente la XAL desde 2015 está sustituyendo el uso del satélite por una red IP que permite conectar su centro en el antiguo recinto de la Maternidad en Barcelona con cada una de sus 132 radios, 32 televisiones digitales terrestres y una docena de medios online IPTV tanto de titularidad pública como privada.

Coincidiendo con esta migración, está abordando también el paso de un entorno en SD a otro en alta definición tanto en distribución como en contribución.

“La fibra nos otorga una solución flexible y económica a largo plazo y gracias a 32 Macrolans de Telefónica podemos disfrutar de un servicio sin apenas latencia”, señala Xavier Cabestany, al frente de los servicios de infraestructuras de la XAL.

“El ahorro en costes de explotación sobre la anterior infraestructura de satélite es considerable, además de mayor flexibilidad, muy bajo retardo y enlaces bidireccionales con QoS. Ha habido que hacer frente retos de distribución del tráfico (se ha optado por IP multicast), gestión del ancho de banda, control centralizado de todos los equipos y herramientas de gestión, adaptación del software a las necesidades específicas, documentación y configuración, formación…”, añade.

Toda esta infraestructura de red es mantenida y gestionada por la Diputació de Barcelona y Telefónica desde su centro de Simancas (Madrid) de forma remota.

Contribución y distribución

One of the key aspects that has allowed the adoption of this network is the improvement in coding technology. In this case, Telefónica (winner of the network deployment tender) uses encoding and decoding solutions Sapec, under the H264 standard which enhances efficient video coding allowing the delivery of high-quality video (high definition) at very low data transmission rates.

In contribution, the XAL has the Sapec Altum-II encoders. The fourth generation of this popular family of encoders allows, with a lower bit-rate, to obtain better image quality with very low total video-to-video latency in an Altum-II. They are highly versatile, flexible, and reliable equipment, designed for operation in 24x7 environments, with high energy efficiency that allows remote configuration and management.

"The Xarxa network is designed so that it can receive contributions from 19 centers, and distribute the signal to the 32 centers of the associated television stations, with Sapec equipment in each of them. Their equipment stands out for its extremely low latency, robustness in communication and low consumption," says Cabestany.

As far as decoding is concerned, the XAL has in each of its associated centers a Gredos de Sapec team. These systems have the capacity to decode signals both MPEG-2 / H.264 both in standard definition and in high definition and are prepared to be able to be updated to decode HEVC. Its IP interface supports reception in both Unicast and Multicast and accepts UDP / RTP streams while giving the possibility of issuing and receiving FEC for error correction according to the SMPTE2022 standard, and it has digital and analog outputs.

The flow of contributions and distribution of signals is managed from the XAL headquarters in Barcelona thanks to the plataforma VideoIPath de Nevion (distributed by Sapec in Spain). The integration of VideoIPath with Altum-II and Gredos equipment is total, allowing a network abstraction layer that allows service providers to provide and monitor services without having to consider detailed configuration parameters in each network element involved.

Additionally, the platform automatically detects available video endpoints by selecting the appropriate video endpoints and service profile. VideoIPath is a very flexible and powerful platform that, among other functions, allows the scheduling (Scheduler) of connections and disconnections for a long period of time, with the system being on a quarterly, monthly, weekly or daily basis. This capacity greatly facilitates the operation of such a complex network where more than 800 connections and 800 disconnections are made weekly. Another of its functions is the administration of bandwidth, achieving more efficient use of the infrastructure with the appropriate quality of service, the management of users, alarms, equipment, etc. And everything accessible from any point through a website.

This scheme allows the entire network to be linked or create “stars” by interconnecting attached entities in certain areas for the contribution or distribution of more local events.

Precisely to bring the XAL even closer to its audience, it have replaced satellite Ka or Ku band links with backpacks with mobile links 3G/4G. The XAL already has a dozen TVU backpacks and four bidirectional Ikusnet ENG (SD) links with dual monitors and bidirectional commands.

On the other hand, XAL has also launched an asynchronous content exchange service developed by VSN (Xarxa Media) basing its archive on the management provided by technology. Tarsys of Tedial. Its tools allow the creation of editing lists and the partial download of content. Both features, together with the possibility of previewing images stored in a low-resolution format based on the H.264 standard, allow you to optimize network resources by minimizing the investment in the communications infrastructure necessary to connect all the associated networks.

Radio

Regarding the radio service, AEQ has supplied the network with almost one hundred and fifty audiocodec Phoenix Venus, developing applications to control and monitor all audiocodecs from any PC connected to the Internet; schedule connections and disconnections; integrate the control with that of the existing audio matrix; activate regional or local outreach groups; and centrally manage contribution point-to-point connections.

La Xarxa has installed a Phoenix Venus audiocodec in each local station. The existing broadcast automation system generates GPOs for the multicast Venus GPIs (MAIN and BACKUP), which it sends to the chosen audiocodec, carrying remote switching commands of the audio source or console control. The control server continually monitors the status of Main and Backup and if the one transmitting fails, it reconnects to the other. Input audio is distributed to both from the matrix.

In contribution, channel 2 of the Local Venus makes contribution towards the central. To do this, in the header there are five contribution Venuses, with two channels each, up to ten simultaneous contributions from different associated stations. These ten bidirectional and stereo channels are connected to the matrix and are connected to the studios to contribute to the program or provide coordination. Calls are established manually from the headend through a phonebook using SmartRTP to establish the call.