Texture Classification Using Multi-resolution Rotation--Invariant Operators
Nanda K. Alapati, Arthur C. Sanderson · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1985
A set of 2-D multi-resolution, rotation-invariant operators is developed. These operators are based on 1-D projection functions which form a basis set for local image patterns. The operators are complex with the magnitude rotation-invariant and the phase carrying directional information. Convolution of an operator with an image yields a complex output image containing magnitude and phase information. Application of a set of such operators at different resolutions to an image yields a set of features which may then be used for classification and phase analysis. The operators are evaluated with respect to their ability to perform texture analysis. Texture classification of four structurally similar textures is performed with better than 90% accuracy of interior regions. Also demonstrated is the ability of the operators to provide orientation information about textures.