华南理工大学学报(自然科学版) ›› 2007, Vol. 35 ›› Issue (8): 49-54.

• 机械工程 • 上一篇    下一篇

基于起点预测的单位十字快速运动估计算法

林兆花 谢存禧 邹焱飚   

  1. 华南理工大学 机械工程学院,广东 广州 510640
  • 收稿日期:2006-09-28 出版日期:2007-08-25 发布日期:2007-08-25
  • 通信作者: 林兆花(1979-),女,博士生,主要从事视频编码和传输研究. E-mail:lin_zhaohua@163.com
  • 作者简介:林兆花(1979-),女,博士生,主要从事视频编码和传输研究.
  • 基金资助:

    粤港关键领域重点突破项目( 20054982304) ;广东省科技攻关项目( 2004B10201010 )

Unit-Rood Fast Motion Estimation Algorithm Based on Starting-Point Prediction

Lin Zhao-hua  Xie Cun-xi  Zou Yan-biao   

  1. School of Mechanical Engineering , South China Univ. of Tech. , Guangzhou 510640 , Guangdong , China
  • Received:2006-09-28 Online:2007-08-25 Published:2007-08-25
  • Contact: 林兆花(1979-),女,博士生,主要从事视频编码和传输研究. E-mail:lin_zhaohua@163.com
  • About author:林兆花(1979-),女,博士生,主要从事视频编码和传输研究.
  • Supported by:

    粤港关键领域重点突破项目( 20054982304) ;广东省科技攻关项目( 2004B10201010 )

摘要: 复杂且耗时的运动估计运算给实时视频编码系统的实现带来了困难.为提高视频编码的实时性,文中分析了运动矢量的分布特性和空间相关性,提出了一种基于起点预测的单位十字快速运动估计算法.该算法结合提前中止准则,通过决匹配绝对误差比较来选择起始搜索点,然后采用羊位十字搜索模式进行搜索.实验结果表明,在保持图像质量基本不变的情况下,该算法搜索速度是三步法的3 -17 倍,是菱形搜索法的2 -9 倍,是自适应十字搜索法的1. 19 -4.42 倍.该算法计算量小,实时性强,易于硬件实现,在小运动序列运动估计方面具有明显优势.

关键词: 视频编码, 运动估计, 搜索算法, 块匹配

Abstract:

Complex and time-consuming computation in motion estimation poses a great challenge to the implementation of real-time video coding. In order to improve the real-time performance in motion estimation , the distribution characteristics and spatial correlation of the motion vectors are analyzed , and a unit-rood fast motion estimation algorithm
based on the starting-point prediction is proposed. In the proposed algorithm , the early stop criterion is adopted to predict the starting-point of search by comparing the sum of absolute difference values of the candidate points , and a unit-rood pattem is used to perform the search. Experimental results show that the proposed algorithm, which is of a searching speed of 3 - 17 times that of the Three~Step Search algorithm , 2 - 9 times that of the Diamond Search algorithm and 1. 19 - 4. 42 times that of the Adaptive Rood Pattem Search algorithm , maintains the picture quality well. Moreover , as compared with other motion estimation algorithms , the proposed algorithm is easy to implement and is of less computational complexity , better real-time performance , and performs better in terms of small motion video sequence.

Key words: video coding, motion estimation, searching algorithm, block matching