Li Lu, Li Wei, Du Qian, Tao Ran
IEEE Trans Cybern. 2021 Sep;51(9):4363-4372. doi: 10.1109/TCYB.2020.2968750. Epub 2021 Sep 15.
Recently, the low-rank and sparse decomposition model (LSDM) has been used for anomaly detection in hyperspectral imagery. The traditional LSDM assumes that the sparse component where anomalies and noise reside can be modeled by a single distribution which often potentially confuses weak anomalies and noise. Actually, a single distribution cannot accurately describe different noise characteristics. In this article, a combination of a mixture noise model with low-rank background may more accurately characterize complex distribution. A modified LSDM, by modeling the sparse component as a mixture of Gaussian (MoG), is employed for hyperspectral anomaly detection. In the proposed framework, the variational Bayes (VB) algorithm is applied to infer a posterior MoG model. Once the noise model is determined, anomalies can be easily separated from the noise components. Furthermore, a simple but effective detector based on the Manhattan distance is incorporated for anomaly detection under complex distribution. The experimental results demonstrate that the proposed algorithm outperforms the classic Reed-Xiaoli (RX), and the state-of-the-art detectors, such as robust principal component analysis (RPCA) with RX.
最近,低秩稀疏分解模型(LSDM)已被用于高光谱图像中的异常检测。传统的LSDM假设异常和噪声所在的稀疏分量可以由单一分布建模,这往往会混淆弱异常和噪声。实际上,单一分布无法准确描述不同的噪声特征。在本文中,低秩背景混合噪声模型的组合可能更准确地表征复杂分布。一种改进的LSDM,通过将稀疏分量建模为高斯混合模型(MoG),被用于高光谱异常检测。在所提出的框架中,变分贝叶斯(VB)算法被应用于推断后验MoG模型。一旦确定了噪声模型,异常就可以很容易地与噪声分量分离。此外,还引入了一种基于曼哈顿距离的简单但有效的检测器,用于复杂分布下的异常检测。实验结果表明,所提出的算法优于经典的Reed-Xiaoli(RX)算法以及诸如带RX的鲁棒主成分分析(RPCA)等先进的检测器。