Método Para Reconhecimento Automático de Placas Brasileiras em Ambientes Não Controlados

V. Ribeiro, V. Greati, I. Silva, A. Martins
SBAI 2017's proceedings

This paper presents a method for brazilian automatic license plate recognition considering images with good illumination and alignment conditions, with lack of illumination, with shadows and with some inclination, taken 1m to 7m far, cases rarely seen in the literature. Images were obtained in a parking lot, during the morning and the afternoon, without environment restrictions. License plate extraction is performed by a cascade of Haar-like features classifiers, built using the AdaBoost algorithm. Filters based on mathematical morphology are used to binarize the plate. Characters are segmented by connected components labelling and are recognized by template matching. Results showed 81.75% of accuracy with average processing times of 210ms and 1304ms for computers with quad-core processors in frequencies 2.2GHz (Dell Inspiron 5588) and 900MHz (Raspberry Pi 2 model B), respectively.