• 中国计算机学会会刊
  • 中国科技核心期刊
  • 中文核心期刊

计算机工程与科学

• 图形与图像 • 上一篇    下一篇

混合鲁棒权重和改进方法噪声的两级非局部均值去噪

陆海青1,2,葛洪伟1,2   

  1. (1.江南大学轻工过程先进控制教育部重点实验室,江苏 无锡 214122;
    2.江南大学物联网工程学院,江苏 无锡 214122)
  • 收稿日期:2016-10-31 修回日期:2017-03-01 出版日期:2018-07-25 发布日期:2018-07-25
  • 基金资助:

    江苏省普通高校研究生科研创新计划(KYLX16_0781,KYLX16_0782);江苏高校优势学科建设工程

Two-stage non-local means denoising based on
hybrid robust weight and improved method noise

LU Haiqing1,2,GE Hongwei1,2   

  1. (1.Ministry of Education Key Laboratory of Advanced Process Control for Light Industry,Jiangnan University,Wuxi 214122;
    2.School of Internet of Things Engineering,Jiangnan University,Wuxi 214122,China)
  • Received:2016-10-31 Revised:2017-03-01 Online:2018-07-25 Published:2018-07-25

摘要:

传统非局部均值去噪算法采用指数型函数计算相似性权重,不能准确反映图像块之间的相似性;现有两级非局部均值去噪算法对方法噪声的获取以及方法噪声中所含信息的利用不够充分。针对上述问题,提出一种混合鲁棒权重和改进方法噪声的两级非局部均值去噪算法。首先采用一种改进的混合鲁棒权重函数来计算图像块的相似性权重;再利用预去噪后的图像构造新的方法噪声,并与两级去噪框架相结合;最后将提出的混合鲁棒权重函数和改进的方法噪声应用到两级非局部均值去噪方法中。实验结果表明,该算法既能准确地反映图像块之间的相似性,也能充分利用方法噪声的信息,且在去噪性能与结构细节保持能力方面均优于传统算法。
 

关键词: 图像去噪, 非局部均值, 方法噪声, 鲁棒权重

Abstract:

Traditional nonlocal means denoising algorithm calculates similarity weight between image patches using exponential functions, which cannot accurately reflect the similarity between image patches. Method noise obtained by existing twostage nonlocal means methods is unsatisfactory, and the information contained  is insufficiently used. Aiming at the problems above, we propose a novel algorithm called twostage nonlocal means denoising based on hybrid robust weight and improved method noise. Firstly, we propose to use an enhanced hybrid robust weight function to calculate the similarity between image patches. Secondly, we use the predenoised image to construct improved method noise, which is then combined with a twostage framework. Finally, the new hybrid robust weight function as well as the improved method noise is applied to the twostage nonlocal means scheme. Experimental results show that the proposed algorithm can calculate the similarity between image patches more precisely and make the best of method noise, and it has better performance in denoising and preserving structure details than traditional ones.
 

Key words: image denoising, non-local means, method noise, robust weight