The Dual Axis Fourier Shape Analysis of Closed Cartographic Forms

AbstractThe authors have developed an approach to the harmonic analysis of closed cartographic forms in the complex domain called Dual Axis Fourier Shape Analysis (DAFSA) which is a significant improvement over earlier harmonic shape analysis techniques. DAFSA is based on the variance spectrum and modulus ratio spectrum as the fundamental Fourier shape descriptors for analysis and interpretation. Any closed cartographic form can be decomposed into its respective harmonic frequency components which can be rationally interpreted in terms of the contribution that a specific frequency and related attributes of it are making to the shape in question. As such the DAFSA descriptors are independent of scale, translation, rotation and starting point of the figure.