A License Plate Recognition and Speed Detection System - Index of

Fig. 25 Image of our LPR/SD system positioned on desk using sun as light source
One major difference between our system and a commercial license plate recognition
system is our use of visible light to illuminate the license plate. Most LPR systems use near-
infrared light. It should be noted that both types of light produce the same effects when shown on
reflective paint. The reflective paint on the license plate causes the license plate to be highly lit
when illuminated by a light source that is placed near the camera aperture. This holds true
whether the light source is emitting visible light or infrared light. It will make it easier for the
image processing algorithms to extract the license plate characters from the image. However,
using visible light for a light source is impractical. Shining bright visible light at passing vehicles
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