Local Shape Representation in 3D: from Weighted Spherical Harmonics to Spherical Wavelets
نویسندگان
چکیده
Both weighted spherical harmonics (SPHARM) and spherical wavelets (SW) have been used for local shape representation of biological structures. In this paper, we shed light on the underlying connections between weighted SPHARM and SW. A novel derivation of SW from weighted SPHARM and a detailed formulation of wavelet transformation for shape representation are presented. Their performances on local shape representation are evaluated on both macro (amygdala) and micro (neutrophil cell) scale images. The experimental results show that SW outperforms the weighted SPHARM for local shape representation of large and complex cell images, while the weighted SPHARM is a good choice for representing small and simpler amygdala.
منابع مشابه
Local Shape Representation in 3D: from Weighted Spherical Harmonics to Spherical Wavelet
Numerous techniques have been proposed for shape representation, including landmarks [1], medial representation [2], spherical harmonics (SPHARM) [3], weighted SPHARM [4], and spherical wavelets (SW) [5]. Among them, both weighted SPHARM and SW have been used for local shape representation of biological structures. Questions we address in this paper are what is the relationship between them, ho...
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