A ne Geometry, Curve Flows, and Invariant Numerical Approximations
نویسندگان
چکیده
A new geometric approach to the a ne geometry of curves in the plane and a ne-invariant curve shortening is presented. We describe methods of approximating the a ne curvature with discrete nite di erence approximations, based on a general theory of approximating di erential invariants of Lie group actions by joint invariants. Applications to computer vision are indicated. y Supported in Part by NSF Grant DMS 92{03398. z Supported in Part by NSF Grants DMS 92{04192 and 95{00931. x Supported in Part by NSF Grant ECS{9122106, by the Air Force O ce of Scienti c Research F49620{94{1{00S8DEF, by the Army Research O ce DAAL03-91-G-0019, DAAH04{93{G{0332, DAAH04{94{G{0054, and by Image Evolutions, Ltd.
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تاریخ انتشار 1997