According to the company Indigovision won the contract to replace Metrorio’s ageing analogue surveillance system because of the superior image quality of the Indigovision cameras, which makes for precise identification of individuals in recorded images, coupled with the flexibility of the IP system, which can be easily scaled up as the metro network grows.

Mr Newton Werneck, CIO of MetroRio stated: "Indigovision's image quality is excellent and the distributed architecture of the system will allow the surveillance network to grow along with the metro system."

Indigovision believes that another crucial factor in winning the business with Metrorio is the system’s highly efficient and economical storage capability. Compared with other IP video systems, storage requirements are significantly reduced thanks to Indigovision’s advanced compression technology and the use of the unique activity controlled framerate (ACF) feature, which is built into the IP cameras. ACF regulates the framerate of the video stream according to the motion in a particular scene. When there is no activity, video is streamed at minimal framerate; the instant any motion is detected, video is simultaneously transmitted at the maximum configured framerate. This responsiveness provides both greater detail for analysis and also allows for economy of data storage.

The Indigovision system also provides Metrorio with improved event archives and content distribution across its network: Indigovision’s unique distributed architecture eliminates the need for a central server, which means that the surveillance system can expand quickly and as required.

IndigoVision’s Brazilian partner Setha Prosegur worked with Metrorio to create the surveillance system, which includes 141 fixed IP cameras, 21 PTZ cameras and approximately 700 existing analogue cameras that have been integrated into the system using Indigovision encoders. An Indigovision NVR-AS 3000 (network video recorder) is in place at each station, with back-up provided between stations.

Founded in 1979 with five stations operating on one line, Metrorio now covers 47km (29 miles) divided into two lines and 35 stations. The network continues to grow with a further line under construction and due for completion in 2016.