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Megapixel cameras versus PTZ

Megapixel cameras can effectively eliminate pan and tilt (PTZ) cameras, writes Paul Taggar, Country Manager UK and Ireland at the US-based megapixel camera manufacturer Arecont Vision.

How might the world of video surveillance have evolved differently if megapixel cameras had been invented before analogue cameras? Consider all the image quality compromises we had to accept over the years because of the limitations of analogue cameras. Think about how we created approaches to try to compensate for low-grade image quality. We designed thousands upon thousands of video surveillance systems in which the accepted resolution standard of 480 TV lines was the weakest link.

One of the ways we sought to compensate for low resolution and field-of-view limitations was the invention of the pan-tilt-zoom (PTZ) device. “Zoom” was needed because analogue cameras couldn’t view objects clearly more than 20 or so feet away, and “pan” and “tilt” were needed to expand coverage for larger areas. Analogue cameras (and IP-based network cameras providing similar resolution at 307,200 pixels) yield a specific, limited resolution that is a constant. System designers had to “work around” that limitation using tools such as mechanical PTZ devices.
The alternative was to add more cameras, which was often cost-prohibitive, especially taking into account both the cost of the cameras and the ancillary costs of installation, recording systems and the need for additional operations staff to monitor the cameras.

But PTZ devices were never a perfect solution and could never quite compensate for the shortcomings of analog images. For example, what is the likelihood that a PTZ camera will be viewing the exact location within a large area at the exact right time to capture an event? It’s much more likely the camera will be looking at the wrong place at the wrong time, even if someone is being paid to guide the camera in real-time.
Another aspect of PTZ devices and cameras is maintenance and product dependability. The devices include mechanical components that need maintenance and are subject to failure over time.

If megapixel cameras had been developed first, one could argue that PTZ devices would never have been invented. Simply put, with megapixel cameras PTZ technology is not needed. By completely transforming how systems are designed and used, higher-resolution megapixel cameras today make PTZ devices obsolete. The development of high-resolution megapixel cameras resolves the issues that PTZ devices have sought – and often failed – to address over the years. The high resolution imaging capabilities of megapixel cameras provide significantly improved fields of view with extreme detail. The ability to electronically zoom into live scenes and recorded video while maintaining high resolution and wide area coverage is simply not possible with conventional analogue or IP PTZ (or fixed) cameras. In addition, when using megapixel cameras, there are no mechanical optics components to fail and no directional issues to contend with. Perhaps most important, megapixel cameras provide a much greater value proposition overall for mainstream video surveillance applications.

Today’s range of available megapixel cameras can provide images at any resolution, from a million pixels up to 40 million pixels or more. System designers can choose whatever resolution they need for a specific application, and they can use fewer cameras, too. For example, a 3 megapixel camera can replace two to five standard-definition VGA (307,200 pixel) cameras. Panoramic and high-megapixel cameras are a real game changer as they can replace dozens of standard-definition cameras, view large areas and “see” everything at once, without the need for mechanical panning, tilting or zooming. Large, clear images can be viewed in real-time or stored and viewed later. Detail permeates the entire field of view and any specific area can be viewed at any time, clearly and close-up. Capturing the whole view negates the need for PTZs and the need for personnel to operate them.

It is therefore inevitable that mechanical PTZ devices will become obsolete. Their demise is a simple and logical result of the superior performance of megapixel cameras, just as digital cameras made photographic film obsolete and touch-tone telephones obliterated the need for rotary dials. However, although the end is near, market forces foretell a lingering death for PTZ devices. “Traditional” security camera manufacturers still enjoy high levels of sales and profits from older technologies, which can dampen enthusiasm about transitioning or even provide motivation to impede progress. Security resellers may also be hesitant to embrace newer technologies, at least until their customers demand it. The perceived technical challenges of IT/IP systems – networks, servers, storage and software – can also give old-school resellers pause until they realise that digital deployment is actually simpler than what they have been doing in the past. But once you see a demonstration of the superior image quality, reduced security operations staff, fewer cameras and cost improvements made possible with new IP megapixel solutions, the picture couldn’t be any clearer.
We can’t change the history of the video surveillance market, but we can certainly transform its future by fully embracing the superior imaging capabilities of megapixel cameras. Fewer cameras, less labour costs and better results all contribute to a far superior return on investment (ROI). And mechanical PTZs will become as passé as slide rules and beepers.

Visit www.ArecontVision.com.


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