This paper deals with the study of different edge detection techniques for plate localization component of a Car License Plate Recognition system. The process of edge detection also involves filtering and smoothing of image. An experimental study has been carried out in this paper for comparison of the available edge detection techniques for this emerging area of application. Single frame gray-level images are used as the only source of information. In the experiment images of Indian license plates were used, which are taken with the Kodak camera 10Mpixels. The results show that the approach is robust to illumination, plate slope, scale, and is insensitive to plate’s country peculiarities. These results could be also usable for other applications in the input-output transport systems, where automatic recognition of registration plates, shields, signs, etc., is often necessary.

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Edges Car license plates Image processing Segmentation and Recognition