Image invariants

A pre-processing technique for image features extraction is presented in the paper. It is based on the algebraic properties of image transform /spl psi/ that are invariant to a given geometrical transformation of an image. A vector space /spl Hscr/ of digital images is introduced. The image invariant is represented by a family of linear maps /spl Rscr/. A linear transform /spl psi/ defined on a space of images /spl Hscr/ pertaining to a given image invariant /spl Rscr/ is constructed. The main idea of this paper is contained in a property of map /spl psi/, that maps all images sharing the same feature described by a family /spl Rscr/ into a single point. The gained information of the digital image extracted by the transform /spl psi/ is suitable for further analysis of image features. Some examples of families /spl Rscr/ are presented. An example of an introduced transform /spl psi/ pertaining to a given family /spl Rscr/ is described.