A Fast and Adaptive Search Algorithm Based on Rood Pattern and Gradient Descent

In order to achieve the real-time property for video coding, a fast and adaptive algorithm based on starting search point prediction and early-termination strategy is proposed. It analyzes center-bias property and spatial correlation property of motion vector field, and utilizes the respective characteristics of block based gradient descent search (BBGDS) and adaptive rood pattern search (ARPS) algorithm. The proposed algorithm adaptively chooses different searching strategies according to the type of the image, makes full use of the cross image motion vector distribution characteristics and optimizes the traditional ARPS algorithm. The experimental results show that the proposed algorithm is about 2.3 similar to 9.2 times faster than Diamond Search (DS), 1.2 similar to 4.0 times than ARPS. The algorithm can meet the real-time demand without reducing the image quality. (C) 2012 Published by Elsevier B. V. Selection and/or peer review under responsibility of ICMPBE International Committee.