Crafting a Smart Traffic Camera Network

From Design to Operation, Paving the Way for Safer Cities

Source: CTV London and City of London

Over the past several years, I had the opportunity to create a new traffic camera program as part of the development of an intelligent transportation system (ITS) in the municipality where I worked. Traffic cameras are instrumental in observing transportation operations activities, providing critical insights into real-time conditions and field situations that need to be managed as part of the operations of a transportation management centre (TMC).

Proving Their Worth

As an initial alarm, data tools such as a travel time detection system or applications such as Waze can be used to identify potential incidents. While their preliminary data may not always be the most accurate in conveying actual conditions in the field, they provide a great early detection system. Then, traffic cameras carry the role of invaluable tools to visually confirm real-time conditions in the field.

To illustrate the value of traffic cameras from my experience, one February we faced a flooding event. At that time before traffic cameras, we had to physically visit different intersections across the city to assess road closures and traffic impacts, which took time. This information was then relayed via text message to our senior manager responsible for changing traffic signal timings on the fly. However, the better approach would have been to utilize a camera system, capturing more geography efficiently to determine impact based on the changing flooding conditions. This incident proved to strengthen the business case in support of traffic cameras.

Once we had cameras installed, assessing impacts became more straightforward. We could easily pull up the camera feed to understand a specific situation, allowing us to adjust traffic signal timings on the fly, provide public service messages, and mitigate situations resulting from collisions or signal malfunctions quickly.

Developing a System

The process of designing, procuring, implementing, and operating a traffic camera program involves several factors that require consideration.

In the planning phase, we focused on determining the best locations along major corridors for these devices across the city. This allowed us to determine optimal locations for dozens of cameras, ensuring the best visual coverage for traffic operators. Specifications for the cameras needed to be established for inclusion in a tender package published for bidders to provide the cameras through a Request for Tenders (RFT) procurement process.

We also had the opportunity to experiment with and test various cameras to better understand their features and operations. I had the opportunity to work directly with brands such as Axis, Bosch, and Hikvision. While there are many other reputable brands on the market, caution is advised, as there are also knockoff brands or those with inadequate security features that may compromise privacy and security. After procuring the traffic cameras, we rigorously undertook both desktop and field testing against the specifications for operations, performance, and cybersecurity compliance. Due diligence is highly recommended!

Mounting the cameras on high poles presented its challenges, requiring research to confirm that the methods and accessories from a specific manufacturer would yield the best view. Factors such as pole height, stability, potential wobbling in windy weather, cabling, and the accessories provided by the camera supplier all needed consideration for optimal mounting height and visual conditions. While some trial and error is inevitable during the pilot installation, it's beneficial to be aware that these considerations are crucial.

There is also a trade-off between PTZ (Pan-Tilt-Zoom) and fixed cameras. Fixed cameras maintain a consistent direction, allowing for the setup of specific detection zones, but cannot rotate, likely requiring multiple cameras at one location. In contrast, PTZ cameras excel in their flexibility to survey the surroundings, zoom in on different events, and assess specific issues.

Lastly, as more cameras are installed, it will become obvious to the public that the traffic cameras are present and being used. It is important to work with your municipal communications team to craft a press release with key messaging to highlight the reason the cameras are present and how they are being used. While inevitable conspiracy theories will likely emerge from some elements of the public, it is still better to get in front of any rumours before they start and ensure transparency in the program.

Privacy Protection

Increasingly, more traffic cameras are incorporating artificial intelligence (AI) algorithms within the firmware to provide image analysis and data collection on the edge. The increasing use of AI also emphasizes the critical nature of privacy protection for the public. Implementing such cameras requires careful adherence to defined rules to ensure privacy is safeguarded. Operators must NOT zoom in on personal details such as vehicle license plates, focus within individual vehicles, or peer into private buildings under any circumstance.

To facilitate responsible use and safeguard public privacy of traffic cameras, we developed a formal policy and code of practice for operators to adhere to. This document outlined the proper utilization of the cameras by business users, specifying the actions permissible for different parties involved. This was a pivotal component in the implementation of the traffic cameras, delineating how they could be employed, how data could be stored, used, and eventually deleted, and the severe consequences that staff members would face if they intentionally violated these practices.

When operating the traffic cameras, incidents are inevitably captured (e.g. collisions). If you choose to record video from the traffic camera continuously, you must expect the need for staff time to respond to inquiries from the public, insurance companies, and law enforcement seeking assistance in investigating incidents. In my opinion, it is more appropriate to use live feeds as the normal operating condition and only record under specific, defined circumstances. It is critical to respect local privacy laws and focus on capturing general traffic trends and incidents vs. any wholesale public surveillance.

Conclusion

Traffic cameras have shown themselves to be an important tool in the realm of intelligent transportation systems. They offer valuable insights into real-time ground conditions and field situations, enabling operators to make swift decisions regarding traffic signals and mitigate unfavourable situations such as collisions or other incidents. I highly recommend their use for such purposes. However, it's imperative to exercise caution and prioritize the protection of public privacy throughout the process.

What have your experiences been operating traffic cameras? Do you find them useful and a worthy investment? Have you tested them with newer AI analytics?