Vector zone plates as test patterns for linear vector filters
Stephen J. Sangwine, Todd A. Ell · Proceedings - International Conference on Image Processing · 2003
Zone plate test images have been used in image processing and television for some time. In this paper the concept is generalized to a vector zone plate, which proves to be a useful test pattern for linear vector filters, in this case colour image filters. The vector zone plate introduced in this paper consists of a radial frequency sweep oscillating between opponent colours. The direction of the opponent colour vectors varies around the image, so that all colours within a plane in colour space are contained within the pattern. Using one of the few examples of a linear vector filter published so far, the paper shows how different vector zone plate patterns may be used to reveal the frequency response of a filter in different directions in colour space.