SPIE Journal Paper | 3 April 2014
KEYWORDS: Cameras, Intelligence systems, Distortion, Optical character recognition, Neural networks, Image segmentation, Visible radiation, Infrared imaging, Infrared radiation, Roads
A large dataset of Persian license plate characters is introduced. These extracted characters are provided by Bani Nick Pardazesh Company, which is a pioneer in the intelligent transportation systems field, and its license plate recognition system has been used for many applications in Iran. Natural scene vehicle images delivered from this company were in various conditions. Most of them were taken with visible light during day and a few of them by infrared light with 850 nm wavelength during night. The vehicle images were achieved by color, black and white, or infrared cameras from front view and back view of automobiles in ∼20 different indoor and outdoor locations, such as streets, roads, and parking lots, for different purposes, such as traffic control, issuing fines, etc. The images are different in size and angle and were taken in light and dark backgrounds, where the direction and intensity of the light varied. Also, some of the license plates were muddy and had parts that were shadowed. Out of all the available images, ∼20,145 Persian characters were extracted by an intelligent system and verified by human observers. The extracted images are different in size, and some of them suffer from elimination, distortion, rotation, and noise.
