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Video Surveillance Resolution

Special Reports

4K Ultra HD is revolutionising resolution in video surveillance says Ed Thompson, CTO DVTEL.

Resolution and clarity in video surveillance has always been a challenge in evidence gathering and investigation analysis. Who hasn’t seen the blurred and choppy images of crime scene getaways on TV shows such as Crimewatch – images that often help the culprits get away with it! Lights, Cameras, No action! Fortunately as with other technologies, camera manufacturers continue to push the boundaries of image clarity to enable catch-up.

Some manufacturers have introduced cameras that can deliver as much as 40-megapixel resolution. However, these cameras can only be used in a very limited number of applications at best and, at worst, merely serve as a marketing gimmick. If you’ve been keeping up with the market, you’ve heard about the buzz around 4K Ultra HD cameras. 4K holds realistic potential. 

Although 10-megapixel cameras, which are essentially the equivalent of 4K cameras in terms of resolution, have been around for years, the devices haven’t exactly generated a lot of excitement or demand from end users. There are several reasons: frame rates and light sensitivity on these cameras are very, very low and the costs of storing high-resolution footage can be high. 

These factors combine to make the deployment of cameras in the 10-megapixel range and above simply out of reach for most users. The difference with 4K is that a new set of high-quality sensors have been developed to accompany these next generation cameras, enabling the cameras to operate at up to 30 frames per second. 

This has significantly changed the quality of the image coming into the camera. At the same time, there have been some breakthroughs on the back end with digital signal processors (DSPs), which can handle larger image formats. With the combination of these new sensors and DSPs, manufacturers can now offer 4K at around the same total cost of ownership as 1080p.

Four times the evidence detail

What does this mean for police and the legal community? Harder evidence and forensic capability, in a nutshell! Users can now have four times the amount of evidentiary detail with minimal impact to storage costs. Those who may have only been able to afford cameras in the 720p to 1080p range can realistically think about using 4K and having much higher quality.

What’s more, 4K provides more forensic zoom and delivers greater detail out of an image than previously possible; even with a higher megapixel camera. Even with the high-quality images from high-definition and megapixels, many users still run into a problem of the image becoming ‘choppy’ or the pixels ‘blocky’ soon after they thedigital zoom.

With 4K, you can zoom in quite a bit further on an image before it degrades. The finer pixel geometry that comes with 4K resolution also results in enhanced video analytic capabilities as algorithms are positively affected by the improved image quality and could, in some cases, even double detection ranges.

While the evidence gathering benefits of 4K resolution are obvious, users still face challenges: primarily network and bandwidth needs, and storage demands.

The workstation processing for many applications also will have to expand substantially in many cases. However, many of these hurdles can be addressed
without the need for extra infrastructure. For example, a 4K camera running at 30fps could operate at 4Mbps, which is no higher than a 1080p camera.

In that case, storage would be virtually unaffected and there would be relatively little impact to a workstation because the decompression rate is about the same, depending on the camera and how it is optimised. Another factor often discussed is the need for a 4K monitor to view the live feed in 4K resolution. Prices of 4K monitors have fallen dramatically in recent months.

Value vs Cost of evidence

Although 4K is still in its early adoption stages, there are enough clear advantages to using 4K to seriously consider the technology now. Those looking to move should consider a package. Complete systems incorporate closely integrated video management software, adaptive streaming, streamlined deployment with plug-and-play, and ease of use through an intuitive drag-and-drop interface.

Indeed, users in a variety of markets have only begun to make the transition to IP-based products, let alone high-definition and megapixel.

Adoption relies heavily on manufacturers and channel partners educating the market about what users can hope to achieve. For some, 4K may just be another offering among many, but others will look to make it their preferred solution. It really comes down to the value versus the cost of the evidence. The value tends to increase with resolutionand, typically, the cost of the evidence rose faster than the resolution, which kept demand for high-resolution in check. Because costs associated with migrating to 4K are minimal, demand for thisimage quality will surge.
