Bas-relief Generation Using Manifold Harmonics Analysis

In this paper a novel algorithm for bas-relief generation from 3D shape is presented based on manifold harmonics spectral analysis.The algorithm focuses on achieving detail-preserving bas-relief independent on the resolution of height field by using exact mesh representation.Firstly,the coordinates of the mesh vertices can be seen as discrete signal,and are transformed to the frequency domain by means of discrete harmonic analysis.During the transformation,the differential geometry properties and topology information of the mesh are utilized.Secondly,according to the proposed definition of energy of harmonic transform coefficients,the frequency is segmented into low,high and noisy frequency bands.Subsequently,the algorithm ignores the noisy frequency component,compresses the low frequency component linearly into a small range,and nonlinearly compresses the high frequency adaptively.Finally,the new frequency is mapped back to space domain by use of reverse harmonic.Experiments demonstrate that the detail on the relief can be enhanced by tuning parameters of an isotropic diffusion filter and using the strategy of spectral segmentation.