Tuesday, November 18, 2014

The Importance of Security Camera Resolution

Luke Latham, CEO, GuardRex Corporation

The topic of camera resolution is probably an abstract subject when you first approach security cameras for your first security system, but it should be one of your important considerations. The detail captured in the images and video provided by the camera can make or break security investigations and court cases following incidents where positive identification is required. In this post, I want to show you what resolution means for security clarity and detail … ultimately identification.

I can demonstrate the problem of low resolution captures with the example below. These are pictures of Doug Cooper, owner of the 7 L Livestock Company in Casper, Wyoming from realranchers.com. The original image is shown at the top. In Image A, I have cropped and enlarged Mr. Cooper from an image captured at a resolution of 2900 x 1933. The image on the right (Image B) is the same area of the original image but starting with a resolution of 725 x 483, one quarter the resolution of Image A. It’s easy to see that the high resolution image provides much better detail.

Doug Cooper, owner of the 7 L Livestock Company, standing in front of one of his oil wells
Original image of Doug Cooper used for the comparison of high and low resolution enlargements
Photo credit: Doug Cooper, owner of the 7 L Livestock Company, at realranchers.com
Doug Cooper headshot
Image A
Doug Cooper, enlarged and cropped image showing clarity and detail of his face taken from a high resolution image
Doug Cooper headshot
Image B
Doug Cooper, enlarged and cropped image showing low clarity and minimal detail of his face taken from a low resolution image

In a security investigation, Image A will be a greater asset to law enforcement in identifying and apprehending the individual. In a court case, a jury might be convinced that the defendant was the person stealing your stroker rods based on the quality of Image A. Of course, Mr. Cooper standing in front of his own pump jack isn’t a suspect here!

When shopping for security cameras, make camera resolution one of the factors you consider. Generally, the greater the resolution the better. This is offset by an important tradeoff: The higher the resolution, the greater the bandwidth required to move images and video over the Internet or over a network. Storage requirements will be higher for the larger high resolution images. The high resolution version of the original image comes in at a hefty 1.3MB, while the smaller low resolution image comes in at a mere 142KB, 11% the size of the high resolution image.

There are no easy rules of thumb for these considerations: Just keep in mind as you choose your cameras that a low resolution choice could hurt you later when the image quality counts. This is especially true when camera coverage must take in a deep field of view. In these cases, objects farther away will be small in the frame (as I show in the Doug Cooper original above) but can be resolved with greater detail when a high resolution image is taken.