计算机应用 ›› 2014, Vol. 34 ›› Issue (10): 2967-2970.DOI: 10.11772/j.issn.1001-9081.2014.10.2967

• 虚拟现实与数字媒体 • 上一篇    下一篇

去除磁共振成像图像莱斯噪声的加权扩散

贺建峰,陈勇,易三莉   

  1. 昆明理工大学 信息工程与自动化学院,昆明 650500
  • 收稿日期:2014-05-12 修回日期:2014-06-11 出版日期:2014-10-01 发布日期:2014-10-30
  • 通讯作者: 陈勇
  • 作者简介:贺建峰(1965-),男,云南开远人,教授,博士,主要研究方向:医学信号处理、模式识别;陈勇(1986-),男,四川泸县人,硕士研究生,主要研究方向:数字图像处理、模式识别;易三莉(1977-),女,湖南岳阳人,讲师,博士,主要研究方向:医学图像处理与分析。
  • 基金资助:

    国家自然科学基金资助项目;教育部回国人员科研启动基金资助项目;云南省人培基金资助项目

Weighted diffusion for Rician noise reduction in magnetic resonance imaging image

HE Jianfeng,CHEN Yong,YI Sanli   

  1. Faculty of Information Engineering and Automation, Kunming University of Science and Technology, Kunming Yunnan 650500, China
  • Received:2014-05-12 Revised:2014-06-11 Online:2014-10-01 Published:2014-10-30
  • Contact: CHEN Yong

摘要:

针对各向同性扩散易于造成图像边缘等特征区域的模糊以及相干增强扩散易于在图像背景区域内产生伪条纹的问题,提出了一种根据磁共振成像(MRI)图像莱斯噪声分布特点来对其进行降噪的加权扩散算法。该算法以MRI图像背景区域的莱斯噪声方差作为区分MRI图像背景区域和感兴趣的边缘特征区域二者特征差异的阈值。基于该阈值,该算法构造了一个加权函数,并用该函数对各向同性扩散和相干增强扩散进行加权。加权函数根据图像在不同结构区域的变化,自适应地调整两种扩散的权值,从而充分发挥两种扩散的优势并克服各自的不足。实验结果表明,该算法在峰值信噪比(PSNR)及平均结构相似度(MSSIM)的评价上优于一些经典算法。因此,该算法的降噪及保护、增强边缘的能力更为优越。

Abstract:

Since the isotropic diffusion will easily blur edge features,and coherence-enhancing diffusion will produce pseudo striations in the background regions during the denoising process, a weighted diffusion algorithm was proposed to reduce the Rician noise of Magnetic Resonance Imaging (MRI) image according to the distribution of noise. A threshold value was calculated by the Rician noise variance in the background region of MRI image, which might be used to distinguish the image background and the edge of Region-Of-Interest (ROI). A weighting function combining the isotropic diffusion and the coherence-enhancing diffusion based on the calculated value was constructed. The constructed function could adaptively adjust the weight values of two kinds of diffusion in different structural regions in order to give full play to the advantages while overcoming the disadvantages of the above two kinds of diffusion.The experimental results show that it is better than some classical diffusion algorithms in Peak Signal-to-Noise Ratio (PSNR) and Mean Structural Similarity(MSSIM).Thus, it has better performance on noise reduction and edge preservation or enhancement.

中图分类号: