April 18, 2013

Surveillance Cameras and the CSI Effect

Crime shows like CSI and NCIS have affected the surveillance industry dramatically. Hollywood exaggerates just how much surveillance systems can ‘see’.

You know the television scenes where all the characters of CSI are standing around a monitor, watching  surveillance video and someone says, “That’s it, right there! Can you enhance that image?” The video tech stops the video and zooms in on an object and after a few key or mouse strokes the suddenly blurry object becomes a knife or a pistol that is clear as a sunny day on the Mojave. This magic bullet of surveillance doesn’t exist int the real world…only in Hollywood.

Why? Recent portrayals of video surveillance has led to many very misinformed customers with unrealistic expectations. The type of surveillance systems used is directly related to the cost and the end result. If the customer wants a CSI style image, then the investment must match.

There are two types of cameras surveillance systems available to the customer today: analog and megapixel.

Traditional or analog cameras are cost effective and inexpensive but result in grainy and fussy images. These systems comprise of over 90% of what is currently in use today in the business world. Analog camera resolution are measured in TVL (TV Lines). A higher number of TVL means that a camera will be able to render images with more detail.

Consider this image from an analog camera a with a resolution of 600TVL. A camera with 600 TVL produces good quality images but has limits. The license plate and text on the van are fuzzy and almost impossible to read at a distance.

11-29-2012Blow up the image to 200% and you get even more fuzzy and impossible to decipher:


A layperson with no surveillance expertise would look at this image and say “well coudn’t my CSI gang ‘enhance’ that image? Not a chance! Video surveillance can follow the axiom of Garbage-In…Garbage-Out. In order to enhance an image or clean it up, you have to begin with a base image that is fairly clean to start with.

Now, let’s look at megapixel cameras. Surveillance camera technology is getting better all the time. There are many great options available and within the price range of the average customer may be able to afford. These systems do carry a higher price tag than its analog cousins.

Consider a pure digital image with 2 megapixels. If a CSI experience is what you desire then you need to fatten the wallet some in order to get an image that gives you the detail needed to ‘enhance’ the image.

Take a look at this image of a parking lot taken with a 2 Megapixel camera:

av81801The field of view in this camera shot has more ‘real estate’ and has significantly more image detail than that its analog cousin. The 2MP image let’s the user clearly identify the tractor trailer at the far end of the parking lot that is from a well known retailer. An analog camera would never deliver this result.

When considering a surveillance system, leave the Hollywood expectations in the livingroom and open your eyes to what surveillance technologies are available in the marketplace and what they truly deliver.

If cost is a driver when purchasing surveillance, you may need to lower your expectations. Making a small blurry picture larger will typical give you a large blurry picture. Analog cameras are cheaper, but can’t and will not get the same image definition as a megapixel camera.