Computer Engineering and Applications ›› 2013, Vol. 49 ›› Issue (7): 195-198.

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Image denoising with adaptive sparse shrinkage method based on SURE estimation

SHA Zhenghu1, YU Jian1, CUI Chen1,2   

  1. 1.Department of Information Engineering, Electronic Engineering Institute of PLA, Hefei 230037, China
    2.Key Laboratory of Electronic Restriction, Anhui Province, Hefei 230037, China
  • Online:2013-04-01 Published:2013-04-15

基于SURE无偏估计的图像自适应稀疏收缩去噪

沙正虎1,余  剑1,崔  琛1,2   

  1. 1.解放军电子工程学院 信息工程系,合肥 230037
    2.安徽省电子制约技术重点实验室,合肥 230037

Abstract: Under sparse representation framework, image denoising problems are investigated over over-complete dictionary and a novel adaptive threshold selection method is presented based on Stein unbiased risk estimator. Based on the one order derivable shrinkage function, the optimal objective function about threshold selection is derived and it is shown to be convex function on threshold, and then its global minimum is searched by golden section method. The choice of threshold is closer to the peak signal to PSNR-threshold curve’s maxima. Lena and Barbara are used in experimental simulation, and the results demonstrate the superior performance of the algorithm.

Key words: sparse representation, shrinkage denoising, general threshold, SURE estimation

摘要: 研究了基于过完备字典下稀疏表示框架的图像去噪问题,基于Stein无偏估计提出一种自适应阈值选择算法。在一阶可导收缩函数的基础上,推导了阈值选择的优化目标函数;证明该函数是关于阈值的凸函数,用黄金分割法搜索其全局最小值。该算法选择的阈值接近峰值信噪比-阈值曲线的极大值点。通过对Lena和Barbara图进行去噪实验,验证了算法的优越性。

关键词: 稀疏表示, 收缩去噪, 通用阈值, SURE无偏估计