Estimation of the Number of Endmembers in Hyperspectral Images Using Agglomerative Clustering

[EN] Many tasks in hyperspectral imaging, such as spectral unmixing and sub-pixel matching, require knowing how many substances or materials are present in the scene captured by a yperspectral image. In this paper, we present an algorithm that estimates the number of materials in the scene using agg...

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Detalles Bibliográficos
Autores: Prades Nebot, José|||0000-0003-4489-3704, Salazar Afanador, Addisson|||0000-0001-5849-5104, Vergara Domínguez, Luís|||0000-0001-6803-4774, Safont Armero, Gonzalo
Tipo de recurso: artículo
Fecha de publicación:2020
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/176146
Acceso en línea:https://riunet.upv.es/handle/10251/176146
Access Level:acceso abierto
Palabra clave:Agglomerative clustering
Principal component analysis
Model-based clustering
Independent component analysis
TEORIA DE LA SEÑAL Y COMUNICACIONES
Descripción
Sumario:[EN] Many tasks in hyperspectral imaging, such as spectral unmixing and sub-pixel matching, require knowing how many substances or materials are present in the scene captured by a yperspectral image. In this paper, we present an algorithm that estimates the number of materials in the scene using agglomerative clustering. The algorithm is based on the assumption that a valid clustering of the image has one cluster for each different material. After reducing the dimensionality of the hyperspectral image, the proposed method obtains an initial clustering using K-means. In this stage, cluster densities are estimated using Independent Component Analysis. Based on the K-means result, a model-based agglomerative clustering is performed, which provides a hierarchy of clusterings. Finally, a validation algorithm selects a clustering of the hierarchy; the number of clusters it contains is the estimated number of materials. Besides estimating the number of endmembers, the proposed method can approximately obtain the endmember (or spectrum) of each material by computing the centroid of its corresponding cluster. We have tested the proposed method using several hyperspectral images. The results show that the proposed method obtains approximately the number of materials that these images contain.