The ancient sculptors, artist, and architects created their masterpieces in accordance with the canons of harmony. The method of symmetry has become a powerful and effective instrument of theoretical research in modern science. A state is said to be homogeneous if it has translation as its symmetry, and isotropic if it has rotation as its symmetry. The goal of an image understanding system is to identify and locate a specified object in the scene. In such cases, the system must have some knowledge of the shape of the desired object.
Symmetries are good candidates for describing shape.
It is a powerful concept that facilitates object detection and recognition in many situations. These representations can be used in robotics for recognition, inspection, grasping, and reasoning. Symmetry in an image allows it to be described economically. For example, if one half of an object is the mirror image of the other half, then one half need not be described. A reflectional symmetry has a reflection line, for which the left half space is a mirror image of the right half.