11 Tactics for Capturing Usable Surveillance Video
I just got back from a law enforcement conference where I was visiting with an industry colleague who provides video enhancement software and service. He was showing me a number of video clips of crime in action which were useless as evidence even with top notch video enhancement software. Many faces couldn't be discerned, license plates were unreadable, and key elements of the crimes were nothing but a blur. Why was this? For starters it's not CSI. We've all seen the crime shows when the residence geek creates visual miracles by feverishly typing a keyboard and rendering a few pixels into a fully fledged picture. He saves the day and they bag the bad guy. This makes for great TV, but in reality it's garbage in and garbage out. The video quality needs to be relatively good to start with in order for video enhancement to make it excellent. Unfortunately, those unusable video clips I was shown are all too common. Clip after clip, I could see simple measures that people could have taken to ensure usable video was obtained. To help increase the odds that your video is either usable or doesn't even need enhancement, here are some tactics to consider: 1. Gear Selection Know what you're buying or consult with an expert. There is a huge range of choices out there, each with strong and weak points for common security applications. That's why it's vital that you spend some time with someone who can give you an accurate prescription for your situation. Video security experts will easily understand the need, and will know the right equipment to use, having seen it in action. 2. Testing Once your gear is selected and purchased, it's important to test it in a working environment. If you have decided to go it alone and not consult with an expert, this step is vital. If for whatever reason the equipment is not delivering clear images, take advantage of an expert now and perhaps an exchange policy as well.
3. Camera Placement Generally speaking, cameras have two jobs — tell you what happened, and who did it. Telling you what happened is the easy part. Sometimes even the cheapest cameras and the poorest of installs can do that, but getting that clear image of the perpetrator can be challenging. The key elements in getting great mug shots are placing the camera in the likely path of travel and keeping the camera down low. If the environment permits, get the camera down to eye level. Cameras placed at this height even defeat the popular tactic of wearing a hoody. 4. Lighting When it comes to lighting, a good rule of thumb is if you can't see then neither can the camera. Cameras need some type of light whether it's natural, building lights, or infrared — it has to be there. The opposite is also true, if you can't see because the light is obstructing your vision the camera won't fair much better. So, insure lighting works to illuminate the area that is visible within the camera's field of view. 5. Optics Lenses are a performance gate for all other components in a system. Cheap lenses will deliver poor results even if thousands of dollars are spent on the best cameras and recorders. Beyond quality, selecting the right lens size to match your need is important. To find the right size, you can use an online lens FOV calculator or estimate it by using a varifocal lens which allows user-selectable fields of view. As a benchmark, 4mm lenses will provide the approximate field of view of a human eye, and the higher the focal length, the more narrow the field of view will be. 6. Cabling Like lenses, many people take cabling for granted as a component of a video security system. Also, like lenses they can be a limiting factor for everything else. High grade cabling will help prevent signal degradation and the introduction of RF noise into the video signal. Even with the best cabling, it's always wise to make sure the cable run is under specified maximum distances and that the cable is not run in parallel with high voltage power lines. 7. Go Covert Using covert cameras in tandem with overt cameras is a tried and tested method of nabbing the bad guy. Why, you might ask? It's simple — if the bad guy doesn't see the camera he doesn't know not to look there. When using covert cameras for this purpose, always place them in likely paths of travel just like you would a visible camera. 8. Go IP IP video systems are not only easy to install and manage; the video quality is awesome. In comparison, analog video systems require analog-to-digital conversion at least once in the process of recording, which diminishes picture quality. Many IP systems, on the other hand, are pure digital end-to-end, maintaining the original images. In addition, many IP video cameras use the progressive scanning method which produces razor sharp images even with fast moving objects like passing cars. Learn more about IP technology.
9. Memory Management In the interest of being able to record for many weeks at a time, people will sometimes lower the resolution and frame rate of their DVR, both of which can save hard drive space. Obviously, losing precious resolution seriously undermines the chances of rock solid identification. When I'm consulting I like to first ask, "If something did happen, when would you become aware and respond?" From there, I recommend a hard drive size to match that time frame while recording at the highest possible resolution and frame rate. Memory these days is very affordable, so why not take advantage of it and get the best evidence possible? Learn more about security DVRs. 10. Maintenance Taking care of a system is just as important as its selection and installation. If you own a video security system, check lenses for dirt, cables for cracks, connectors for corrosion, ensure the equipment is still getting the proper voltage, and so on. There is a lot more I could expand upon but even doing the simple things like removing the dirt off the lens of an IR camera will make a huge difference. 11. Upgrades If you purchased your security system from a professional source, everything should be industry standard. This means you can take advantage of the latest advancements in security cameras and recorders and keep your system providing you with the very best insurance. For example, replacing cameras that are a few years old with wide dynamic cameras that use advanced processors to balance out tough light conditions will dramatically increase chances of positive identification. If you invest in these steps to maximize the quality of your video, the payback will be substantial in providing you with an increased level of protection and better evidence should the need arise to provide evidence of a crime.