Dual-Weighted Lp-Norm RPCA Model and Its Application in Salt-and-Pepper Noise Removal
Author:
Affiliation:
Faculty of Information Technology, Beijing University of Technology, Beijing 100124, China
Fund Project:
摘要
|
图/表
|
访问统计
|
参考文献
|
相似文献
|
引证文献
|
资源附件
摘要:
鲁棒主成分分析(Robust principal component analysis,RPCA)模型中秩函数和L0范数的求解是非确定性多项式(Nondeterministic polynominal,NP)难问题,凸近似模型的求解通常会导致过收缩。本文结合加权方法和Lp范数提出了一种基于双加权Lp范数的RPCA模型,利用加权Sp范数低秩项和加权Lp范数稀疏项分别对RPCA框架中的低秩恢复问题和稀疏恢复问题进行建模,使其更接近秩函数和L0范数最小化问题的解,提升了矩阵秩估计和稀疏估计的准确性。为了验证模型性能,本文利用图像的非局部自相似性,结合相似图像块组的低秩性与椒盐噪声的稀疏性,将双加权Lp范数鲁棒主成分分析模型应用于去除椒盐噪声过程中。定量与定性的实验结果表明,本文模型性能优于其他模型,同时奇异值过收缩分析也表明本文模型能够有效抑制秩成分的过度收缩。
Abstract:
The robust principal component analysis (RPCA) model aims to estimate underlying low-rank and sparse structures from the degraded observation data. Both the rank function and the L0-norm minimization in the RPCA model are nondeterministic polynominal(NP)-hard problems, which usually are solved by the convex approximation model, so leading to the undesirable over-shrinkage problem. This paper proposes a dual-weighted Lp-norm model based RPCA model by combining the weighting method and the Lp-norm. We use the weighted Sp-norm low-rank term and the weighted Lp-norm sparse term to model the low-rank and sparse recovery problems under the RPCA framework, respectively, which provides better approximations to the rank minimization and the L0-norm minimization, thus improving the accuracy of the rank estimation and the sparse estimation. To further demonstrate the performance of the proposed model, we apply the dual-weighted Lp-norm RPCA model to remove the salt-and-pepper noise by exploiting the image nonlocal self-similarity and combining the low rank of similar image patch matrices and the sparsity of salt-and-pepper noise. Both qualitative and quantitative experiments demonstrate that the proposed model outperforms other state-of-the-art models, and the singular value over-shrinkage analysis experiment also demonstrates that the model can better deal with the over-shrinkage problem of the rank components.
图1 测试图像Fig.1 Test images
图2 Plants图像去噪结果(10%椒盐噪声)Fig.2 Denoised results on image Plants (10% salt-and-pepper noise)
图3 House图像去噪结果(30%椒盐噪声)Fig.3 Denoised results on image House (30% salt-and-pepper noise)
图4 Monarch图像去噪结果(50%椒盐噪声)Fig.4 Denoised results on image Monarch (50% salt-and-pepper noise)
图5 低秩矩阵的奇异值分析Fig.5 Singular value analysis of low rank matrices
图8 最大迭代次数对复原结果的影响Fig.8 Influence of the maximum number of iterations
表 1 不同椒盐噪声概率情况下各种去噪方法的PSNR/SSIM比较Table 1 Comparison of different denoising methods under different salt-and-pepper probabilities in terms of PSNR/SSIM
表 2 不同椒盐噪声概率情况下的参数设置Table 2 Parameter setting with different salt-and-pepper probabilities