联合改进LBP和超像素级决策的高光谱图像分类
Hyperspectral Image Classification Combining Improved Local Binary Mode and Superpixel-level Decision
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摘要: 高光谱图像在有标签样本数目较少的情况下进行分类时,除了利用光谱特征外,空间纹理特征也是必不可少的。本文提出了一种利用多尺度多方向局部二值模式(LBP)描述子获取纹理特征,并结合超像素级指导决策的支持向量机分类方法。首先,本文方法将传统LBP描述子改进为多尺度多方向LBP描述子,一方面充分考虑了邻域像素之间的关系,另一方面在计算时分别考虑了水平垂直方向和对角方向。其次,在利用统计直方图获得纹理特征时,采用了多个尺寸窗口组合的方式,以获得多范围、高精度的纹理特征。第三,对传统的简单线性迭代聚类(SLIC)超像素分割方法进行改进,重新定义了光谱距离并引入了纹理特征距离,获得更精确的超像素分割图。最后,利用超像素分割图结合多数投票策略,对分类结果进行进一步的指导校正。实验表明,本文方法能够更有效的提取纹理特征,再结合超像素分割图的指导决策,进一步提升高光谱图像的分类性能。Abstract: Hyperspectral images to be classified with a small number of labeled samples, in addition to using spectral features, spatial texture features are also indispensable. This paper proposed a support vector machine (SVM) classification method that uses multi-scale and multi-directional Local binary mode (LBP) descriptors to obtain texture features and combines super-pixel level to guide decision. First, the method in this paper improved the traditional LBP descriptor into a multi-scale and multi-directional LBP descriptor. On the one hand, the relationship between neighboring pixels was fully considered, and on the other hand, the horizontal and vertical directions and diagonal directions were considered in the calculation. Second, when using statistical histograms to obtain texture features, a combination of multiple size windows was used to obtain multi-range, high-precision texture features. Third, the traditional super pixel segmentation method, simple linear iterative clustering (SLIC) was improved, the spectral distance was redefined and the texture feature distance was introduced to obtain a more accurate super pixel segmentation map. Finally, the super-pixel segmentation map combined with the majority voting strategy was used to further guide and correct the classification results. Experiments show that the proposed method can extract texture features more effectively, combined with the guiding decision of superpixel segmentation maps, and further improve the classification performance of hyperspectral images.