Edge and line enhancement by adaptive lattice filtering. [Haar transform]
John E. Brolley · OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information) · 1979
Digitized images were two-dimensionally transformed to the Haar sequency domain. High-sequency boosting was performed, and the inverse Haar two-dimensional transform, applied. The resulting image was then raster-scanned with a continuously adaptive lattice filter. This procedure was applied to a simple image of a photographic step tablet and a complex scene. All of the lines of the step tablet were well defined over the whole dynamic range. Useful definition of lines in the complex scene was obtained. 10 figures.