ANPR (Automatic Number Plate Recognition)

There are three major steps to number plate reading.
1. Locating and isolating the number plates in the image (read about the plate finding algorithm).
2. Locating and isolating the characters in the number plate.
3. Reading the characters (OCR, optical character recognition).

I have developed a system which reads number plates from any digital image, color or monochrome, sizes range from 640×480 to megapixel images (1280×720 is a practical upper limit in many cases).

The algorithms are written in the C language to make them very fast and portable (easily deployed in embedded applications). The algorithms are packaged with a sample system developed as a C#/.Net application.

Here is the source code for the licence plate reading algorithms, including the plate finding, character segmentation, and the OCR. Warning, its not documented.

If you find it useful, then please send me bits of documenation or explanation or improvements, and I will post them for follow on users. My contact info is on the About page.

link to source code


sample plate source image

plate finding development tool

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