The next generation of onboard cameras
The arrival of the ARTPEC-7 chip, the latest generation system-on-a-chip designed by Axis for the specific demands of video surveillance, has brought benefits across the entire Axis portfolio of surveillance cameras, and is now doing the same for onboard cameras. Erik Mårtensson, Global Product Manager for Onboard Cameras, explains: “Across all types of Axis cameras, the ARTPEC-7 chip delivers numerous enhancements in image processing, analytics capabilities, compression efficiency and firmware security. The ability to undertake analytics at the edge of the network is something we’ll come back to, but some of the greatest steps forward delivered by ARTPEC-7 in onboard cameras comes through improved performance in challenging light conditions, one of the critical demands for onboard cameras.”
From bright sunlight to complete darkness: performance in all light
Humans themselves know the problems that can arise when moving quickly from darkness into bright light - and vice versa - and while our eyes are quick to adjust, cameras can take longer, and in this additional time important details could be lost. While cameras installed on buildings or structures that don’t move have a longer time to adjust to changing light conditions, vehicles and trains are constantly moving through different light, and onboard cameras need to cope with the rapid changes.
“Any moving vehicle – be it a bus, tram, train, ambulance or delivery van – can be facing north, east, south and west and all points in between every few minutes,” says Mårtensson. “The position of the sun, moving clouds, fog and rain all affect light, as does moving under bridges and through tunnels. The main principle in the design of our onboard cameras is that they are purpose-built for changes in light. To that end, in addition to the broader enhancements, for the first time one of our new cameras also features integrated IR to allow for clear images even in pitch darkness.”
Built-in invisible IR-LEDs are found in the new AXIS P3935-LR and deliver clear images in absolute darkness, ideal for vehicles travelling in poorly-lit rural locations at night, or when lighting inside the vehicle would cause discomfort for passengers. As the IR-LEDs in the new camera operate at the higher 940nm wavelength, they will not show as red dots seen in traditional IR-LEDs, further improving safety and comfort for the driver and passengers. The integration of other Axis technologies, including Lightfinder and Forensic WDR, deliver optimal performance in low light and strong backlight, for instance when the camera is directly facing bright sunlight.
The challenges of stops, starts, bumps and potholes
Dealing with constantly changing light is one challenge for onboard cameras. Another, of course, is movement. A moving vehicle - particularly one that regularly stops and starts - causes plenty of its own vibrations. Add to this bumpy roads or tracks and onboard cameras installed in forward-facing position can find keeping images stable and clear a challenge. For the first time, the two new cameras include an integrated accelerometer which, alongside the in-built gyro, support Electronic Image Stabilization (EIS), delivering smooth images outside the vehicle in all conditions. In addition, for those cameras installed facing forward on fast-moving vehicles, the cameras’ variable frame rate will be invaluable, allowing up to 45fps. This is an important feature for capturing details at a high-speed, for instance if a train hits an obstruction on the track.
The potential for edge analytics
With the image quality assured whatever the conditions, thoughts can turn to what to do with the information returned. Again, the use of ARTPEC-7 has created a transformation in analytics capabilities. Mårtensson again, “One of the major enhancements delivered through ARTPEC-7 is the ability to undertake analytics on the ‘edge’ of the network, in the camera itself, rather than on the server in the data center. Not only does this mean that actions based on analytics can take place much more rapidly, it opens up an almost unimaginable number of opportunities for analytics applications.”
Previously, transferring data from an onboard camera for analysis was complex and prohibitively expensive. To think that this might then be returned to the vehicle as an alert with low enough latency was impossible to consider. Analytics in the camera itself opens up a world of possibilities for analytics with safety, security and operational benefits. Many of these applications will be delivered by members of the Axis Developer Partner (ADP) Program, using the AXIS Camera Application Platform (ACAP).
Patrik Anderson expands on the potential for analytics: “As an example, people counting and passenger demographic analytics can provide valuable business intelligence that enable transport authorities to optimize their routes and services. These days, they can also be used to mitigate public health risks by measuring seat occupancy and social distancing compliance. Appropriate analytics would also be able to monitor the top deck of a double-decker bus and alert the driver to any issues or play an automated announcement.”
The integrated microphone in one of the new cameras can also create alerts based on verbal aggression or stressed voices, further enhancing passenger safety. Aggregated and anonymized analytics data will also prove invaluable to transport operators in service design and optimization, tailoring services for busy and quieter parts of the day, creating efficiencies and improving the customer experience. And from an environmental perspective, data from analytics based on the camera’s accelerometer could be used in training drivers more eco-efficient, smoother driving styles, and will be a useful addition to accident investigation.
The potential for analytics is enormous, and will significantly enhance the investment in the new onboard camera models. “Ultimately, the main purpose of onboard cameras is to deter and mitigate security risks happening onboard vehicles of all types. With the addition of edge analytics, the number of incidents can be reduced significantly,” Anderson adds.
Power in a small package
A lot of new technology and capability has been packed into the two new cameras, but with no change in form or size. This is a critical point. Many vehicles that feature onboard cameras – particularly buses, trains, trams – are expensive investments and expected to have a useful life of many decades. The onboard cameras, on the other hand, are more likely to be replaced every few years as their capabilities increase. It is essential, therefore, that new models are the of same modest size and ‘footprint’ as previous models.
But added to the fact that the new cameras feature a highly impact-resistant metal casing, they pack a lot into a small package. As Mårtensson concludes: “The new models look much the same as previous ones – it’s only when you pick them up that you sense the amount of new technology that’s been built-in!”