An efficient fully parallel thinning algorithm

The paper addresses an efficient parallel thinning algorithm based on weight-values. The weight-value of a black pixel is calculated by observing neighboring pixels, and it gives one an efficient way to decide whether the pixel is deleted or not. Owing to weight-values, the proposed algorithm uses only 3×3 templates. Furthermore, it examines only the elimination conditions corresponding the weight-value of boundary pixels, and all elimination conditions will not be searched as most other parallel iterative thinning algorithms. Thus, the execution time can be reduced a lot compared to that of previous approaches. The weight-value also allow one to deal with typical troublesome patterns efficiently. Without smoothing before thinning, the algorithm produces robust thinned images even in the presence of two pixel-width noises. The authors obtain encouraging results from extensive experiments