Wang Yiting, Huang Shiqi, Liu Zhigang, Wang Hongxia, Liu Daizhi
Xi'an Research Institute of Hi-Tech, Xi'an, Shanxi, China
Xijing University, Xi'an, China.
Appl Spectrosc. 2016 Sep;70(9):1573-81. doi: 10.1177/0003702816665992. Epub 2016 Aug 26.
In order to reduce the effect of spectral variability on calculation precision for the weighted matrix in the locality preserving projection (LPP) algorithm, an improved dimensionality reduction method named endmember extraction-based locality preserving projection (EE-LPP) is proposed in this paper. The method primarily uses the vertex component analysis (VCA) method to extract endmember spectra from hyperspectral imagery. It then calculates the similarity between pixel spectra and the endmember spectra by using the spectral angle distance, and uses it as the basis for selecting neighboring pixels in the image and constructs a weighted matrix between pixels. Finally, based on the weighted matrix, the idea of the LPP algorithm is applied to reduce the dimensions of hyperspectral image data. Experimental results of real hyperspectral data demonstrate that the low-dimensional features acquired by the proposed methods can fully reflect the characteristics of the original image and further improve target detection accuracy.
为了降低光谱变异性对局部保留投影(LPP)算法中加权矩阵计算精度的影响,本文提出了一种改进的降维方法,即基于端元提取的局部保留投影(EE-LPP)。该方法主要利用顶点成分分析(VCA)方法从高光谱图像中提取端元光谱。然后通过光谱角距离计算像素光谱与端元光谱之间的相似度,并以此为依据在图像中选择相邻像素,构建像素间的加权矩阵。最后,基于加权矩阵,应用LPP算法的思想对高光谱图像数据进行降维。真实高光谱数据的实验结果表明,该方法获取的低维特征能够充分反映原始图像的特征,并进一步提高目标检测精度。