License Plate Reader
Effective security equipments for vehicles
License Plate Readers (LPR) have been around for over 30 years. One of the common misconceptions about LPR is the ability to read 100% of license plates 100% of the time. Although a great idea, this is simply not possible. End-users and manufacturers often have different ideas regarding the ability for automated License Plate Readers to see and read plates with such high accuracy.
Security professionals should expect the highest accuracy reads possible. Leading the industry with a proven 95% plus read rate and the only License Plate Reader manufacturer to include state/province or country identification as part of the read, we feel it necessary to describe what we cannot guarantee as part of this specification.
At Perceptics, we like to say, “If you can see it, we can read it.” But what constitutes an unreadable license plate? Here are a few examples:
· License plate missing from the vehicle
· License plate outside of the camera(s) field of view, which include:
· Damaged license plates, which include:
o Portions of the plate are missing
o Plate is bent or otherwise distorted in a manner that alters the shape of characters that constitute origin or registration number
· Plates mounted in a manner inconsistent with the law of the state entered, such as a plate displayed in the rear window of a passenger vehicle or anywhere other than the intended place
· Obstructed plates
o An object, such as a the ball of a trailer hitch, prevents clear view of origin or the registration number
o Any object that obscures the outline of origin or registration number, such as a license plate frame
Broken or obstructed characters on a plate also qualify as an unreadable plate. A character is considered to be obstructed by an object if the silhouette of the object in question overlaps any portion of the character. Obstructions are caused by objects in the path of the imager (the camera) to the target (the license plate).
It is important when comparing License Plate Reader systems that the customer understands how readable and unreadable plates factor into the performance accuracy equation being promoted by the manufacturer.