Algorithm for sub-pixel line width measurement based on the orthogonal Legendre moment
WANG Boxiong, YANG Chunyu, LI Wei, QIN Yao
State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments and Mechanology, Tsinghua University, Beijing 100084, China
Abstract:Line width measurements are of great importance for detecting small objects. An algorithm is developed for sub-pixel line width measurements based on the orthogonal Legendre moment. The line width is converted into the sum of two different symmetrical line widths. The 0th, 2nd and 4th order orthogonal Legendre moments are used to develop expressions for the symmetrical line widths. Template coefficients of the moments are derived for analyzing digital images and the principle error is analyzed and corrected. Tests of the algorithm for measuring the line widths of standard particles in ampoules show that the algorithm is accurate and efficient.
王伯雄, 杨春毓, 李伟, 秦垚. 基于Legendre正交矩的亚像素线宽测量方法[J]. 清华大学学报(自然科学版), 2016, 56(2): 218-222.
WANG Boxiong, YANG Chunyu, LI Wei, QIN Yao. Algorithm for sub-pixel line width measurement based on the orthogonal Legendre moment. Journal of Tsinghua University(Science and Technology), 2016, 56(2): 218-222.
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