Network cameras

Choosing an HDTV, megapixel or standard resolution camera

One of the unique benefits that network video brings to the video surveillance market is the ability to move beyond the traditional PAL/NTSC resolution and frame rate limitations and experience high-resolution video with extreme image detail. Even a 1 megapixel network camera offers a resolution that is at least three times better than an analog CCTV camera, and there are network cameras that offer as much as 8 megapixel resolution – and beyond.

Choosing the right camera for your system can easily become a challenge. These guidelines help you optimize your camera installation based on how you need to use your video to fulfill your video surveillance goals.

HDTV network cameras

HDTV network cameras are a recent technology development that has gained enormous interest on the video surveillance market. As for megapixel, HDTV means excellent image detail, but in addition, a true HDTV network camera complies with industry standards which ensure excellent color representation, full frame rate and a 16:9 format.

Which are the suitable applications for megapixel network cameras?

HDTV means that the image is very pleasing to eye, with full frame rate video and excellent color representation. It provides a wide-screen 16x9 image, perfect for modern screens and TVs. The fact that true HDTV network cameras comply with key industry standards means that image quality is guaranteed to a higher degree than for many megapixel network cameras. HDTV network video is superb for applications where full frame rate is prioritized.

Airports, casinos, city surveillance, passport controls are some examples where HDTV network video is a perfect solution to achieve image usability.

Megapixel network cameras

Megapixel network cameras do not adhere to any standards, but is rather an adaptation of the industry’s best practices and refers specifically to the number of image sensor elements of the digital camera. For example, multi-megapixel network cameras often offer a limited frame rate.

Which are the suitable applications for megapixel network cameras?

Megapixel network cameras are excellent for many applications, for example when video with extreme image detail is required, such as in overview surveillance of banks, transportation hubs and other premises.

In addition, some megapixel cameras offer “multi-view streaming”, which means that the same camera can deliver different video streams from different areas of a scene, which essentially leads to one megapixel camera replacing several standard cameras – for example, by monitoring more than one cashier in a retail store. Digital pan/tilt/zoom is another advantage offered by megapixel cameras.

Standard resolution cameras

Even with the advantages provided by megapixel and HDTV cameras, there are many application areas where standard resolution network cameras provide the best solution. Standard resolution typically means VGA (640 x 480 pixels) resolution, which in many applications is more than enough to meet the video surveillance goals. Recently, SVGA network cameras have appeared on the market which provide higher resolution (800 x 600 pixels), while still not delivering megapixel images.

When are standard resolution cameras the best choice?

With the abundance of standard resolution cameras on the market it is easy to find a solution for most applications. Cameras with powerful optical zoom are the perfect answer to many monitoring situations. And in scenes with difficult lighting, there are standard resolution cameras with extreme light sensitivity and wide dynamic range that provides image usability well beyond what an HDTV or megapixel network camera can typically achieve in those conditions. Some cameras provide frame rates higher than the traditional 25/30 frames per second offering the perfect solution to capture fast moving objects.

Not the least, when optimizing the video surveillance installation, it is critical to take the whole system into account, and not just the cameras. Video management software, network capacity and video storage requirements often set limits for resolution and frame rate, and standard resolution cameras can often become the most cost-efficient solution.

Conclusion

There is no single type of camera that is appropriate for all applications. Only by carefully analyzing the goals of your video surveillance installation can the right requirements be defined. Often the answer lies in combining HDTV network cameras and megapixel network cameras with a selection of standard resolution network cameras that are optimized for other needs. By balancing different types of network cameras, an IP-Surveillance solution can be designed that is effective, reliable and cost-efficient and fulfills the desired image usability.

Next topic: Light sensitivity