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arXiv · 0906.4907

On the difference between solutions of discrete tomography problems II

Birgit van Dalen
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Abstract

We consider the problem of reconstructing binary images from their horizontal and vertical projections. It is known that the projections do not necessarily determine the image uniquely. In a previous paper it was shown that the symmetric difference between two solutions (binary images that satisfy the projections) is at most 4A times the square root of 2N. Here N is the sum of the projections in one direction (i.e. the size of the image) and A is a parameter depending on the projections. In this paper we give a lower bound: for each set of projections that has at least two solutions, we construct two solutions that have a symmetric difference of at least 2A+2. We also show that this is the best possible.

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Birgit van Dalen. 2009-06-26. On the difference between solutions of discrete tomography problems II. https://arxiv.org/abs/0906.4907

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