Video developments in automatic incident detection
First publishedin ITS International
An emergency incident response exercise under way at the Tyne Crossing.
David Crawford reviews technological progress with automatic incident detection
Highway safety problems are likely to intensify given recent predictions of future traffic growth across the world. In the United States, the National Highway Traffic Safety Administration (NHTSA) reports that currently over 30,000 deaths and 1.5 million injuries occur as the result of accidents on the nation’s roads each year.
These figures will increase with the number of kilometres travelled each year in the US expected to grow by 60% between 2010 and 2030, with the growth figure for truck kilometres predicted at 75%. Reflecting these statistics, the use of cameras for traffic management and automatic incident detection (AID) continues to grow worldwide.
New York based ABI Research calculates that global annual spending on CCTV surveillance and monitoring networks will rise to US$2bn by 2014. Supporting technology is developing in parallel; while the need to monitor and analyse the growing number of video feeds being produced has created corresponding demands for specialist support in the form of AID software.
The 1990s introduction of internet protocol (IP) based cameras equipped to send and receive data directly (centralised with a central network video recorder in 1996; decentralised, with their own in-built recording capability in 1999) has dramatically changed the market for CCTV surveillance networks, with implications for most analogue system components.
Advantages include locational flexibility, scalable video analytics and remote accessibility. Kristof Maddelein, of Belgian systems supplier Traficon, predicts that within five years, 80% of the company’s customers will be opting for decentralised IP systems.
One issue for traffic managers is when and how to make the switch from analogue to digital. They need to affect the change in a cost managed way that extends the life of existing equipment as far as is economic.
For most sites, this migration will take place gradually. During the process, analogue and IP solutions will have to coexist, in some cases, for many years to come.
“This issue is one that is exercising a lot of our customers,” says Citilog vice president for North America and Northern Europe Eric Toffin. The company is currently working on the migration from analogue to IP of two of its largest installations in the US.
The hardware is common to both systems. Toffin says: “This allows for gradual migration without too much degradation of the service – eight to 16 cameras at a time. Worldwide, we have around 400 sites that wil be migrating over the next five years.”
One instance of large scale migration, involving the New Jersey based monitoring and surveillance specialist Infinova, is the Shenzhen Transportation Surveillance System, which serves the southern Chinese mainland’s major financial centre and the site of the country’s first ‘special economic zone’.
The Shenzhen Traffic Bureau is the primary driver of a planned city-wide multimodal ITS deployment seen as eventually forming part of a national transport management system. The bureau was facing the fact that most of its existing camera arrays, including those operated by the Huanggang traffic management centre, were analogue. These needed to be upgraded into a fully integrated multimodal transport management array, covering port and public transport as well as highway operations. The ultimate aim was move to IP.
Instead of tearing out the old analogue cameras and their communications links, the bureau decided to leverage the existing array while starting the migration to a fully digital network by creating a hybrid system that could work with the older equipment. This meant adding encoders to the original analogue cameras, along with a management server and streamed media transmission server.
The Florida DOT Smart SunGuide transportation management center (TMC)
The bureau’s control centre now uses an Infinova V2015 matrix switcher, with network video encoders and decoders used for single-way video channel connection with highway traffic and other control centres. With the switcher carrying out network control, these other transport management centres have been spared the need for new fibre-optic connections.
In the world of IP system development, Traficon’s early 2011 launch of its VIP (video image processor) product marked the securing of several key contracts. The module inputs real-time video images from network cameras, with image processing algorithms running in parallel to deliver a multi-functional detector board and allowing function selection depending on specific needs or camera positions.
Designed to connect to a range of IP cameras and to support MPEG4 as well as new H264 video compression technology, the Traficon system uses the standard real time streaming protocol (RTSP), with digital recording of pre and post incident video sequences. All video decoding and encoding is carried out in hardware.
Early deployments include the NZ$340M (US$265M), 450m cut-and-cover Victoria Park Tunnel in Auckland, New Zealand, built to remove a severe bottleneck on the motorway network connecting with the Auckland Harbour Bridge. The AID array, based on 10 VIP-IP modules, has had to be seamlessly integrated with a DYNAC traffic management system supplied by US based Transdyn to the New Zealand Transport Agency (NZTA), using Traficon’s Flux software platform for collecting video data.
Another implementation, this time in the UK, is on the the £260M (US$401M) New Tyne Crossing, completed in November 2011 to double the capacity of a key road link under the River Tyne between Newcastle and Gateshead in North East England. The opening of a new bore has allowed full refurbishment of the original tunnel; both are now equipped with an array of 83 VIP-IP cameras.
A key challenge for Traficon was to integrate its AID installation with a fixed fire suppression system (FFSS) supplied by the German supplier Fogtec.
The first tunnel FFSS implementation in the UK, this releases a fine mist aimed at containing any fire that breaks out. The aim is to allow drivers to escape safely and minimise the risk of damage to the tunnel structure, by mitigating the heat produced and enhancing the effectiveness of the emergency services in dealing with a smaller fire than would otherwise develop.
In the US, completion is due by Spring 2012 of the largest deployment worldwide to date of Citilog’s VisioPad system for the Florida Department of Transportation (FDoT). The agency is expanding its traffic monitoring capability along interstate highways I-95, I-595 and I-75 in Broward County, the second most populous county in the State. An existing array of 45 CCTV cameras, set at approximately 1.6km intervals, is being upgraded to a more dense arrangement of 222 units – all IP and pan-tilt-zoom (PTZ) – following an FDoT policy decision not to deploy fixed cameras.
The cameras are feeding information into the FDoT District Four Smart SunGuide transportation management centre (TMC), which began operating in 2004. Eric Toffin says: “It quickly became apparent that real time monitoring of the many video inputs was stretching the TMC operators' ability to focus. The CCTV cameras were mostly being used to confirm incidents already signalled to operators from other sources such as highway patrols or calls from road users”.
FDoT therefore decided to move to the proactive, as opposed to reactive, use of CCTV cameras. Citilog secured the contract through its Canadian partner Fortran Traffic Systems.
Toffin says: “The expanded system is bringing to the attention of the FDoT operators a significant number of incidents that would not otherwise have been seen, or would have been picked up much later, delaying intervention and worsening congestion.”
The system allows video detection units to operate directly on digitally encoded video feeds and supply ‘snapshots’ from all connected cameras for display on the FDoT Smart SunGuide website. Posts to the website allow road users to view traffic conditions in real time – helping to make it one of the most popular of all DOT sites.
The system is being fully integrated with FDoT's SunGuide advanced traffic management software, developed to allow traffic operators to fully control all subsystems within the same graphical user interface.
One of Citilog’s most recent developments involves a hybrid of VisioPaD and a fixed camera system. The idea is to combine the functionality of the latter with the flexibility of the self-calibrating VisioPaD.
“This cannot work on every system because there is still a need for integration with the video management process, which is not always a trivial matter. So the decision to use one or the other will be based on serious cost/benefit analysis,” says Toffin. “A number of our customers will stick to VisioPaD because of its simplicity of deployment. Others may have a sensitive issue for which the hybrid system will be necessary and will be worth the effort put into the integration”.