[Editor's note: John Honovich publishes this and other information on network video at IPVideoMarket.info.]
Designing a video surveillance solution requires decisions on 7 fundamental questions. This tutorial walks the reader through each issue explaining the basic options and the rationale for selecting different options.
This is a survey to help those new to video surveillance (and the first chapter of theÂ "Security Manager's Guide to Video Surveillance" 2nd Edition book). Its goal is to quickly identify the key aspects of video surveillance design, not to examine the many details and edge cases in such designs.
The 7 fundamental questions are:
- What type of cameras should I use?
- How should I connect cameras to video management systems?
- What type of video management system should I use?
- What type of storage should I use?
- What type of video analytics should I use?
- How should I view my surveillance video?
- How should I integrate video with my other systems?
Cameras are literally the eyes of a video surveillance system. Cameras should be deployed in critical areas to capture relevant video.
The two basic principles of camera deployment are (1) use chokepoints and (2) cover assets.
Chokepoints are areas where people or vehicles must pass to enter a certain area. Examples include doorways, hallways and driveways. Â Placing cameras at chokepoints is a very cost-effective way to document who entered a facility.
Assets are the specific objects or areas that need security. Examples of assets include physical objects such as safes and merchandise areas as well as areas where important activity occurs such as cash registers, parking spots or lobbies. Â What is defined as an asset is relative to the needs and priorities of your organization.
Once you determine what areas you want to cover, there are 4 camera characteristics to decide on:
- Fixed vs PTZ: A camera can be fixed to only look at one specific view or it can be movable through the use of panning, tilting and zooming (i.e., moving left and right, up and down, closer and farer away). Â Most cameras used in surveillance are fixed. Â PTZ cameras are generally used to cover wider fields of views and should generally be used only if you expect a monitor to actively use the cameras on a daily basis. Â A key reason fixed cameras are generally used is that they cost 5 -8 times less than PTZs (fixed cameras average $200 - $500 USD whereas PTZ cameras can be over $2,000 USD).
- Color vs Infrared vs Thermal:Â In TV, a video can be color or black and white. Â In video surveillance today, the only time producing a black and white image makes sense is when lighting is very low (e.g., night time). In those conditions, infrared or thermal cameras produce black and white images. Infrared cameras require special lamps (infrared illuminators) that produce clear image in the dark (but are significantly more expensive than color cameras - often 2x to 3x more). Thermal cameras require no lighting but product only silhouettes of objects and are very expensive ($5,000 - $20,000 on average) In day time or lighted areas, color cameras are the obvious choice as the premium for color over black and white is trivial.
- Standard Definition vs. Megapixel:Â This choice is similar to that of TVs. Â Just like in the consmer world, historically everyone used standard definition cameras but now users are shifting into high definition cameras. Â While high definition TV maxes out at 3 MP, surveilance cameras can provide up to 16 MP resolution. Â In 2008, megapixel cameras only represent about 4% of total cameras sold but they are expanding very rapidly. See a demonstration of megapixel cameras to learn more.
- IP vs Analog:Â The largest trend in video surveillance today is the move from analog cameras to IP cameras. Â While all surveillance cameras are digitized to view and record on computers, only IP cameras digitize the video inside the camera. Â While most infrared and thermal cameras are still only available as analog cameras, you can only use megapixel resolution in IP cameras. Currently, 20% of cameras sold are IP and this percentage is increasingly rapidly.