Relief Extraction and Editing
Authors: Yin Chena, Zhi-Quan Chenga,b, Jun Lia, Ralph R. Martinb, Yan-Zhen Wanga
DOI: 10.1016/j.cad.2011.07.011
Abstract:
Bas-reliefs are widely used in the world around us, for example, on coinage, for branding products, and for sculptural decoration. Reverse engineering of reliefs|extracting existing reliefs from input surfaces|makes it possible to apply them to new items; relief editing tools allow modi cation of reverseengineered reliefs. This paper presents a novel approach to relief extraction based on di erential coordinates, which o ers advantages of speed and precise extraction. It also gives the rst method in the literature speci cally designed for relief editing. The base surface is estimated using normal smoothing and Poisson reconstruction, allowing a relief (which may lie on a smooth or textured input surface) to be automatically extracted by height thresholding.
We also provide a range of relief editing tools, also using di erential coordinates, permitting both global transformations (translation, rotation, and scaling) of the whole relief, as well as local modi cations to the relief. Our relief editing algorithm, unlike generic mesh editing algorithms, is speci cally designed to preserve the geometric detail of the relief over the base surface.
The e ectiveness of our methods is demonstrated on various examples of real industrial interest
