Component Issues
One of the most noticeable trends in megapixel surveillance is intelligence. Analytics are being baked into the latest DSPs from Texas Instruments and Hisilicon, making basic algorithms — people counting, motion detection, missing object detection and tracking — nearly universal on megapixel cameras. “Basic intelligence would be motion detection; then, next are some more advanced analytics that go beyond to things we haven't thought of yet,” said Vance Kozik, PM at StarDot Technologies.
Analytics take advantage of faster processors and increased pixel counts. This makes edge devices suited for detail recognition, particularly for facial or license plate recognition that requires zoom, said Philip Siow, Senior Consultant for South APAC, Axis Communications.
While most megapixel cameras support basic analytics, they will support more intelligent access control and intrusion functions, said Ebony Huang, President and CEO of Brickcom.
HD or megapixel cameras are expected to become smarter with analytics and storage on the edge, changing video system architecture from server-centric to edge-centric and providing reductions in TCO. “With fewer servers to buy, install and maintain, coupled with a lighterweight network when not streaming the recording video back to the servers, the system becomes cheaper and easier to install and maintain,” Thompson said.
A smarter camera that puts less stress on the network will enable megapixel cameras to handle 24/7 recording. “There are also a few trade-offs to consider,” Christensson said. “Higher resolution and pixel rates require more processing, and features such as WDR will further add to the DSP cycles needed, requiring low-power ISP implementations.”
Higher pixel density will require higher processing power for the infrastructure, said William Ku, Director of Brand Business for Vivotek.
Image Sensors
Objectively, there are some benchmarks for identifying a megapixel camera with a good sensor. “Look at the pixel size,” Schreiber said. “Do not trust any of the sensitivity figures, because there is no standard.”
To combat poor low-light sensitivity, IR illuminators boost image sensor performance. “For side-by-side low-light performance, a CCD is more light-sensitive than a CMOS sensor,” Kozik said.“However, that is beginning to change.”
More pixels in megapixel sensors will generate more noise at night. “The performance with IR lighting for night conditions is quite important because there are some megapixel implications, particularly with IR-cut filter switching sometimes not being as smooth as a typical CCD camera,” Moody said.