This paper addresses the problem on how to evaluate various operators used for estimation of derivatives in images. Such operators are extremely commonly used, for instance to detect edges. For bandlimited correctly sampled signals ideal derivative operators are easy to define. For 2D signals the fi
Rotation invariance in gradient and higher derivative detectors
โ Scribed by Per-Erik Danielsson; Olle Seger
- Publisher
- Elsevier Science
- Year
- 1989
- Weight
- 143 KB
- Volume
- 48
- Category
- Article
- ISSN
- 0734-189X
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โฆ Synopsis
We develop a technique using general moments to find the orientations of 2D planar orthographic projections of 3D objects, even if the 3D object has a completely unknown structure. The technique should open new classes of biological materials for ultrastructural analysis, through molecular scale transmission electron microscopy reconstruction applications where the original 3D object's structure is unknown. In machine vision applications where the full 3D structure is known, the technique provides a fast and computationally efficient way to orient projections. The techm'que can also be used to orient 1D line projections of 2D unknown objects.
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