A Rapid Recognition Approach for the Display Value of Circular Instrument

摘要

A rapid recognition approach for the display value of circular instrument is proposed. Firstly, the instrument image is mapped into the polar-exponent space, so the circular dial is flattened. Secondly, a polygonal approximation method for triangular pointer detection is proposed. According to the triangle's coordinates, the digits areas in the instrument image are located and segmented. Finally, the local asymmetric statistical characteristics are calculated, which are used for constructing a SVM classifier. Experiments show that the method could accurately locate the instrument pointer and achieve high digital recognition accuracy.