Comparative study of different dimensionality reduction methods in hyperspectral image classification

Abstract

Considering the high-dimensional characteristics of hyperspectral image (HSI) data, researchers generally adopt the dimensionality reduction (DR) methods to reduce the complexity and computing time of subsequent classification or regression tasks while preserving the intrinsic structure information of the data. At present, the research on DR of HSIs data mostly focuses on the application performance of a single method in specific tasks and few studies have been conducted on the adaptability of different DR methods to HSIs data. From the perspective of spectral domain and spatial domain, this paper makes a comparative study on the performance of various linear and nonlinear DR methods in the task of HSI classification of aerial HSI of Matiwan Village in Xiongan New Area. Specifically, it includes principal component analysis, independent component analysis, isometric mapping, Laplacian eigenmaps, autoencoder, etc. The results show that the intrinsic structure in Xiongan HSI is mainly linear structure. Compared with the nonlinear DR methods, the linear DR methods can better preserve the intrinsic structure information of data at a lower time-consuming cost. For the subsequent classification tasks, the linear DR methods have better classification performance and are more suitable for HSI data.