Skewed Symmetry Groups
نویسندگان
چکیده
We introduce the term skewed symmetry groups and provide a complete theoretical treatment for 2D wallpaper groups under aÆne transformations. For the rst time, a given periodic pattern can be classi ed not simply by its Euclidean symmetry group but by its highest \potential" symmetry group under aÆne deformation. A concise wallpaper group migration map is constructed that separates the 17 aÆnely deformed wallpaper groups into small, distinct orbits. The practical value of this result includes a novel indexing and retrieval scheme for regular patterns, and a maximalsymmetry-based method for estimating shape and orientation from texture under unknown views.
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تاریخ انتشار 2001