CGT: A fast thinning algorithm implemented on a sequential computer

A new approach, called contour generating (CG) is proposed to reduce drastically the running time for the parallel thinning algorithms on a sequential computer by providing an amount of extra storage space. As a result, the time complexity of the parallel thinning algorithm using this technique becomes proportional only to the object area of the image instead of the product of the whole image area and the maximum half-width of the object. With its application to the classical thinning (CLT) algorithm, a new algorithm called the contour generating thinning (CGT) algorithm is introduced. The experimental results show that CGT is so far the fastest of all reported thinning algorithms, and the skeletons produced are of good quality.