计算机工程与应用 ›› 2014, Vol. 50 ›› Issue (3): 125-128.

• 图形图像处理 • 上一篇    下一篇

[L1-L2]正则化的图像复原交替优化算法

肖  宿,洪留荣,沈  克,郑  颖   

  1. 淮北师范大学 计算机科学与技术学院,安徽 淮北 235000
  • 出版日期:2014-02-01 发布日期:2014-01-26

[L1-L2] regularization based alternating optimal algorithm for image restoration

XIAO Su, HONG Liurong, SHEN Ke, ZHENG Ying   

  1. School of Computer Science and Technology, Huaibei Normal University, Huaibei, Anhui 235000, China
  • Online:2014-02-01 Published:2014-01-26

摘要: 为快速且准确地重建原始图像,提出一种新的图像复原算法。在稀疏表示的框架下,建立图像复原问题的约束优化模型,同步估计原始图像及其稀疏表示。复原模型的目标函数包含[L1-L2]双正则项,为此采用交替优化将模型分解为若干子问题,交替迭代求解这些子问题。其中不可微分的子问题,由迭代重加权方法进行处理。实验结果表明,仅需较少次迭代该算法即可获得原始图像及其稀疏表示的最优估计。与某些优秀的同类算法相比,该算法的速度更快,复原图像的质量更高。

关键词: 图像复原, 交替优化, 稀疏表示, 正则化, 迭代重加权方法

Abstract: For rapidly and accurately restoring images, a novel image restoration algorithm is presented. In the framework of sparse representation, a new constrained optimization model is created, which enables the estimations of the original image and its sparse representation. The objective function of the model has [L1-L2] regularized terms, thus the alternating optimization method is introduced to decompose the model into equivalent sub-problems. The non-differentiable one among sub-problems is handled by iterative reweighted method. The experimental results demonstrate that with only a few iterations, the presented algorithm can achieve optimal estimations of the original image and its sparse representation. Compared with some state-of-the-art algorithms, the presented algorithm shows to be faster, and obtains better results.

Key words: image restoration, alternating optimization, sparse representation, regularization, iteratively reweighted method