Wavelet-domain edge modeling with applications to image interpolation
Bo Tao, M.T. Orchard · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2000
Edge modeling in the wavelet domain is important to efficient image compression and accurate image interpolation among many other applications. In this work, we first analyze the properties of an edge in different scales. By using simple models for edges and wavelet filters, we show how edge coefficients in one scale relate to edge coefficients in another scale in both magnitude and phase, which we call scale coherence. Real image data are used to verify the goodness of the model. We further propose to use spatial coherence, i.e. the structural correlation of edge signals with their spatial neighbors, as additional tools to locate an edge. The model enables us to predict the edge coefficients in a high- frequency band by inspecting their counterparts in previous high-frequency bands and in their spatial neighborhood, and is applied to image interpolation.