Published on 11 July, 2007
To monitor traffic conditions and maintain safety at distant locations, transfer of video images of exceptional quality is crucial. A SISTORE CX video-over-IP solution from Siemens integrates analogue cameras with an intelligent digital video codec, providing outstanding image quality of the Gotschna Tunnel at a superior cost/performance ratio.
The Gotschna Tunnel, opened in Switzerland at the end of 2005 with a length of 4.2 km, and is part of the Klosters by-pass and the federal highway A28 extension between Landquart and Davos. The tunnel reduces travel time to tourist destinations and the traffic burden of local communities. Safety technology is state-of-the-art; fire alarm systems, emergency lights, a hydrant pipeline, measuring equipment for CO2 concentration, visibility regulation, traffic control, video monitoring facilities, SOS telephones, fire extinguishers, and tunnel radio technology for police and maintenance services.
Video monitoring as a challenge
Video monitoring of the Gotschna Tunnel is part of traffic safety for the Cantonal Police of Grisons; images reach the police force's control room in Chur - more than 30 kilometres away. Emergency situation analysis and adequate response depend on outstanding images. The canton's Civil Engineering Office faced the challenge of selecting video monitoring and data transmission equipment for the 29 analogue cameras distributed through the length of the Gotschna Tunnel. A Gigabit Ethernet connected to an ATM network, standard upon installation five years ago, would be used to transfer image data and control signals.
Video-over-IP offered a viable solution for data transmission, with the most important criteria being image quality and cost/performance ratio, followed by the possibility to eventually replace analogue equipment with digital. The resulting solution was a virtual video matrix, which could digitalise analogue camera signals using an encoder, transfer them via the Ethernet network and subsequently convert digital signals to analogue using a decoder.
Best in test: the SISTORE CX video codec
"The Civil Engineering Office of Grisons subjected four systems to tests under simulated conditions. The intelligent digital video codec SISTORE CX was the clear winner," explains Sandro Mura, responsible for information technology at the Grisons Civil Engineering Office. He continues, "The decisive factors were the excellent image quality and a convincing cost/performance ratio."
Flexibly scalable and versatile
SISTORE CX is an encoder and decoder, providing video motion detector, streaming and recording on a digital platform. Its flexible scalability and versatile implementation provide advantageous options. Web-based access across the entire network is simple via LAN/WAN. Image data is compressed using MPEG4, enabling real-time recording and optimum transmission in DVD quality.
In each of the two sub-stations in Selfranga and Drostobel, three SISTORE CX units extract image data to be encoded from a single matrix. At the Cantonal Police Headquarters in Chur, the same number of SISTORE CX units scan the data from the WAN, decode and transfer it to the ATM network (and therefore to the control room) using a codec.