Sammon mapping for preliminary analysis in Hyperspectral Imagery

The main goal of this paper is to present the implementation of the Sammon algorithm developed for finding N points in a lower m-dimensional subspace, where the original points are from a high n-dimensional space. This mapping is done so interpoints Euclidian distances in m-space correspond to the d...

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Bibliographic Details
Main Authors: Nicolae APOSTOLESCU, Daniela BARAN
Format: Article
Language:English
Published: National Institute for Aerospace Research “Elie Carafoli” - INCAS 2016-03-01
Series:INCAS Bulletin
Subjects:
Online Access:http://bulletin.incas.ro/files/apostolescu__baran__vol_8_iss_1_f.pdf
Description
Summary:The main goal of this paper is to present the implementation of the Sammon algorithm developed for finding N points in a lower m-dimensional subspace, where the original points are from a high n-dimensional space. This mapping is done so interpoints Euclidian distances in m-space correspond to the distances measured in the n-dimensional space. This method known as non-linear projection method or multidimensional scaling (MDS) aims to preserve the global properties of points. The method is based on the idea of transforming the original, n-dimensional input space into a reduced, m-dimensional one, where m<n, and it may be used to clustering hyperspectral data. The Principal Component Analysis (PCA) may be applied as a pre-processing procedure for starting, in order to obtain the N points in the lower subspace. The algorithm was tested on hyperspectral data with spectra of various lengths. Depending of the size of the input data (number of points), the number of learning iterations and computational facilities available, Sammon mapping might be computationally expensive.
ISSN:2066-8201
2247-4528