On finding the axes of skewed symmetry using the image normalization with moment
Toshinori Yoshikawa, Izumi Iida · Systems and Computers in Japan · 1993
Abstract Among the reconstruction methods for three‐dimensional information, methods are known for extracting the axes of skewed symmetry that place constraints on the orientation of the plane in space. Since skewed symmetry loses the symmetric nature for the most part, the many earlier methods for extracting axes of symmetry could not be directly applied to extracting axes of skewed symmetry. In addition, conventional methods for extracting the axes of skewed symmetry have the drawbacks of having long processing times and being difficult to apply to complex figures. In this paper, we propose a method that uses moments to perform a first‐order transform on a skew symmetric figure into a symmetric figure and then extracts the axes of symmetry. In this method, the problem is simplified by transforming a skew symmetric figure into a symmetric figure so that conventional methods for extracting the axes of symmetry can be applied. In addition, the evaluation of symmetry which uses the fact that the areas on both sides of an axis of symmetry are equal is adopted in the proposed extraction of the axes of symmetry. The features of this method are discussed by giving practical examples of extracting the axes of skewed symmetry.