稀疏差异先验信息支持的高光谱图像稀疏解混算法

Sparse hyperspectral unmixing algorithm supported by sparse difference prior information

基于光谱库的高光谱稀疏解混技术近年来得到了人们的关注,该技术利用光谱库中光谱样本作为端元,将解混问题转化为稀疏表示问题。然而,由于测量环境的差异,待解混图像的实际端元往往与光谱库中相应光谱信号存在差异。本文提出了一种光谱差异稀疏约束的联合稀疏回归解混算法。首先,假设光谱差异具有稀疏特性,建立了光谱库校正模型,使得在解混过程中可对光谱库进行自适应地调整;然后,将光谱库校正模型与联合稀疏回归解混模型结合,建立了考虑光谱差异的稀疏解混模型;最后,基于交替方向乘子法得到了迭代优化解决方案。分别利用仿真和真实高光谱数据进行了试验验证,结果表明,在光谱库不匹配的情形下,本文方法能够有效提高稀疏解混算法的解混性能。

Spectral library-based hyperspectral sparse unmixing technology has received attention in recent years,which uses spectral samples in the spectral library as endmembers and transforms the unmixing problem into a sparse representation problem.However,due to differences in the measurement environment,the actual endmembers of the hyperspectral image to be unmixed tend to differ from the corresponding spectral signatures in the spectral library.In this paper,an unmixing algorithm named spectral difference sparse constrained collaborative sparse regression is proposed.Firstly,we assume that the spectral differences have sparse property,and a spectral library correction model is established,which can make the spectral library be adaptively adjusted during the unmixing process;Then,the spectral library correction model is combined with the collaborative sparse regression unmixing model to establish a sparse unmixing model considering spectral differences;Finally,an iterative optimization solution based on the alternating direction method of multipliers is given.Synthetic and real hyperspectral data are used to verify the performance of different algorithms.The results show that the proposed algorithm is more effective than the compared algorithms in the presence of spectral library mismatches.