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arXiv · 1707.05062

Speeding up the K\"ohler's method of contrast thresholding

Guillaume Noyel
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Abstract

K{\"o}hler's method is a useful multi-thresholding technique based on boundary contrast. However, the direct algorithm has a too high complexity-O(N 2) i.e. quadratic with the pixel numbers N-to process images at a sufficient speed for practical applications. In this paper, a new algorithm to speed up K{\"o}hler's method is introduced with a complexity in O(N M), M is the number of grey levels. The proposed algorithm is designed for parallelisation and vector processing , which are available in current processors, using OpenMP (Open Multi-Processing) and SIMD instructions (Single Instruction on Multiple Data). A fast implementation allows a gain factor of 405 in an image of 18 million pixels and a video processing in real time (gain factor of 96).

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Guillaume Noyel. 2017-07-17. Speeding up the K\"ohler's method of contrast thresholding. https://doi.org/10.1109/icip.2017.8296295

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