Evaluating pixel-based vs. object-based image analysis approaches for lithological discrimination using VNIR data of WorldView-3.

Shayeganpour, Samira; Tangestani, Majid Hashemi; Homayouni, Saeid ORCID: https://orcid.org/0000-0002-0214-5356 et Vincent, Robert K. (2021). Evaluating pixel-based vs. object-based image analysis approaches for lithological discrimination using VNIR data of WorldView-3. Frontiers of Earth Science , vol. 15 , nº 1. pp. 38-53. DOI: 10.1007/s11707-020-0848-7.

Prévisualisation

PDF Télécharger (2MB) | Prévisualisation

Résumé

The object-based against pixel-based image analysis approaches were assessed for lithological mapping in a geologically complex terrain using Visible Near Infrared (VNIR) bands of WorldView-3 (WV-3) satellite imagery. The study area is Hormuz Island, southern Iran, a salt dome composed of dominant sedimentary and igneous rocks. When performing the object-based image analysis (OBIA) approach, the textural and spectral characteristics of lithological features were analyzed by the use of support vector machine (SVM) algorithm. However, in the pixel-based image analysis (PBIA), the spectra of lithological end-members, extracted from imagery, were used through the spectral angle mapper (SAM) method. Several test samples were used in a confusion matrix to assess the accuracy of classification methods quantitatively. Results showed that OBIA was capable of lithological mapping with an overall accuracy of 86.54% which was 19.33% greater than the accuracy of PBIA. OBIA also reduced the salt-and-pepper artifact pixels and produced a more realistic map with sharper lithological borders. This research showed limitations of pixel-based method due to relying merely on the spectral characteristics of rock types when applied to high-spatial-resolution VNIR bands of WorldView-3 imagery. It is concluded that the application of an object-based image analysis approach obtains a more accurate lithological classification when compared to a pixel-based image analysis algorithm.

Type de document:	Article
Mots-clés libres:	object-based image analysis; pixel-based image analysis; lithological mapping; Worldview-3; Hormuz Island; spectral angle mapper; support vector machine
Centre:	Centre Eau Terre Environnement
Date de dépôt:	10 juin 2021 15:21
Dernière modification:	13 juin 2023 20:51
URI:	https://espace.inrs.ca/id/eprint/11760

Gestion Actions (Identification requise)

Modifier la notice