Freeform Surface Filtering Using the Lifting Wavelet Transform

Texture measurement for simple geometric surfaces is well established. Many surface filtration techniques using Fourier, Gaussian, wavelets ... etc, have been proposed over the past decades. These filtration techniques cannot be applied to today’s complex freeform surfaces, which have nonEuclidean geometries in nature, without distortion of the results. Introducing the lifting scheme open the opportunity to extend the wavelet analysis to include irregular complex surface geometries. Using the second generation wavelets and the lifting scheme, a method of texture filtration for freeform surface data is proposed in this paper. Results and discussion of the application of this method to simulated and measured data are presented.