Alpr camera
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Having The Most readily useful Alpr Camera
The Slate camera system delivers the high performance expected from Federal Signal�s PIPS Technology in a compact, low-profile form factor. Designed for today�s low profile lightbars, the Slate does not hinder visibility to the lightbar. In conjunction with the SupeRex III Mobile ALPR Processor and PAGIS software, the Slate camera provides a turnkey, high-performance, feature-rich ALPR system unlike any other. The system uses lighting (such as Infra-red) and a camera to take the image of the front or rear of the vehicle which is then analyzed by image-processing software, which extracts the image and the plate information. This data is then used for enforcement or record collection and maintenance.
Try using the manual thresholding option. At the moment iSpy only works with alphanumeric plates and may have problems with reversed plates (white on black for example) - although this is untested ( let us know! ). Also OCR requires a good resolution to be accurate. Use a high quality camera and / or move the camera closer to the license plate you want to detect. Commercial license plate cameras use resolutions of several megapixels - so it's unlikely you will get good results from a 320 x 240 webcam! Some of the systems can even store the photographic image of the driver of the vehicle.
Mounted on a car it can �actively� seek out and check thousands of plates per hour while just driving around. Sure, I hear many people say, so what? I have nothing to hide, so who cares? It is a valid point of view, but it is flawed. Previous to the installation of ALPR equipment, the Beverly Hills Police Department performed license plate checks much like the standardized routine used by law enforcement throughout the country. When a plate of interest was observed, the police officer typed the number into a mobile data terminal (or he may have�radioed the plate number in).
The recognition system used in ALPR differs with difference in the license plates formats. In different states, the license plate numbering formats are different. In that case, the same optical reader cannot be used. Some alphabets are not allowed in some states, but the reader must recognize them as well. Further, the fonts and size may differ with vehicles registered in different countries. These minute differences have to be monitored by the reader and the number has to be identified properly. The recognition program utilized in ALPR differs with distinction in the license plates formats. In diverse states, the license plate numbering formats are distinct.
With ALPR, the stolen vehicle only has to pass a police cruiser; if the plate number is in the database, the system will let the officer know. The system will also inform the officer if the driver is known to be armed and dangerous, so the officer can choose to pursue discreetly rather than pull the suspect over immediately. During one shift, an experienced police officer using this method might be expected to process up to 150 plates. But�in a patrol vehicle equipped with ALPR cameras, that same officer could check several hundred to several thousand plates in one shift�and not even have to�take his hands off the wheel.
