Enhancing CCL Algorithms by Using a Reduced Connectivity Mask

Abstract

In this paper, we propose to use a Reduced Connectivity Mask (RCM) in order to enhance connected component labeling (CCL) algorithms. We use the proposed RCM (a 2×2 spatial neighborhood) as the scanning window of a Union-Find labeling method and of a fast connected component labeling algorithm recently proposed in the literature. In both cases, the proposed mask enhances the performance of the algorithm with respect to the one exhibited by each algorithm in its original form. We have tested the two enhanced approaches proposed here against the fast connected component labeling algorithm proposed by He and the classical contour tracing algorithm. We have compared their execution time when labeling a set of uniform random noise test images of varying occupancy percentages. We show detailed results of all these tests. We also discuss the differences in behavior shown by the set of algorithms under test. The RCM variants exhibit a better performance than the previous CCL algorithms.