A Simple Parallel Convex Hulls Algorithm for Sorted Points and the Performance Evaluation on the Multicore Processors

Abstract

Finding a vast array of applications, the problem of computing the convex hull of a set of sorted points in the plane is one of the fundamental tasks in pattern recognition, morphology and image processing. The main contribution of this paper is to show a simple parallel algorithm for computing the convex hull of a set of n sorted points in the plane and evaluate the performance on the dual quad-core processors. The experimental results show that, our implementation achieves a speed-up factor of approximately 7 using 8 processors. Since the speed-up factor of more than 8 is not possible, our parallel implementation for computing the convex hull is close to optimal. Also, for 2 or 4 processors, we achieved a super linear speed up.