How to Color a Checkerboard with a Given Distribution - Matrix Rounding Achieving Low 2×2-Discrepancy
نویسندگان
چکیده
Motivated by a digital halftoning application to convert a continuous-tone image into a binary image, we discusses how to round a [0; 1]-valued matrix into a f0; 1g binary matrix achieving low discrepancy with respect to the family of all 2 2 square submatrices (or regions). A trivial upper bound of the discrepancy is 2 and the known lower bound is 1. In this paper we shall show how to achieve a new upper bound 5=3 using a new proof technique based on modi ed graph matching.
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