Download PDF

PLoS One

Publication date: 2017-08-01
Volume: 12 17
Publisher: Public Library of Sciene

Author:

Sauwen, Nicolas
Acou, Marjan ; Halandur Nagaraja, Bharath ; Sima, Diana ; Veraart, Jelle ; Maes, Frederik ; Himmelreich, Uwe ; Achten, Eric ; Van Huffel, Sabine

Keywords:

SISTA, Science & Technology, Multidisciplinary Sciences, Science & Technology - Other Topics, SVD BASED INITIALIZATION, Algorithms, Brain, Brain Neoplasms, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Pattern Recognition, Automated, PSI_MIC, PSI_4358, General Science & Technology

Abstract:

Non-negative matrix factorization (NMF) has become a widely used tool for additive parts-based analysis in a wide range of applications. As NMF is a non-convex problem, the quality of the solution will depend on the initialization of the factor matrices. In this study, the successive projection algorithm (SPA) is proposed as an initialization method for NMF. SPA builds on convex geometry and allocates endmembers based on successive orthogonal subspace projections of the input data. SPA is a fast and reproducible method, and it aligns well with the assumptions made in near-separable NMF analyses. SPA was applied to multi-parametric magnetic resonance imaging (MRI) datasets for brain tumor segmentation using different NMF algorithms. Comparison with common initialization methods shows that SPA achieves similar segmentation quality and it is competitive in terms of convergence rate. Whereas SPA was previously applied as a direct endmember extraction tool, we have shown improved segmentation results when using SPA as an initialization method, as it allows further enhancement of the sources during the NMF iterative procedure.