NMF vs. ICA for Light Source Separation under AC Illumination

Ruri Oya, Ryo Matsuoka, Takahiro Okabe

2020

Abstract

Artificial light sources powered by an electric grid change their intensities in response to the grid’s alternating current (AC). Their flickers are usually too fast to notice with our naked eyes, but can be captured by using cameras with short exposure time settings. In this paper, we propose a method for light source separation under AC illumination on the basis of Blind Source Separation (BSS). Specifically, we show that light source separation results in matrix factorization, since the input images of a scene illuminated by multiple AC light sources are represented by the linear combinations of the basis images, each of which is the image of the scene illuminated by only one of the light sources, with the coefficients, each of which is the intensity of the light source. Then, we make use of Non-negative Matrix Factorization (NMF), because both the pixel values of the basis images and the intensities of the light sources are non-negative. We experimentally confirmed that our method using NMF works better than Independent Component Analysis (ICA), and studied the performance of our method under various conditions: varying exposure times and noise levels.

Paper Citation

in Harvard Style

Oya R., Matsuoka R. and Okabe T. (2020). NMF vs. ICA for Light Source Separation under AC Illumination. In Proceedings of the 15th International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications (VISIGRAPP 2020) - Volume 4: VISAPP; ISBN 978-989-758-402-2, SciTePress, pages 460-465. DOI: 10.5220/0009150804600465

in Bibtex Style

@conference{visapp20,
author={Ruri Oya and Ryo Matsuoka and Takahiro Okabe},
title={NMF vs. ICA for Light Source Separation under AC Illumination},
booktitle={Proceedings of the 15th International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications (VISIGRAPP 2020) - Volume 4: VISAPP},
year={2020},
pages={460-465},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0009150804600465},
isbn={978-989-758-402-2},
}

in EndNote Style

TY - CONF

JO - Proceedings of the 15th International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications (VISIGRAPP 2020) - Volume 4: VISAPP
TI - NMF vs. ICA for Light Source Separation under AC Illumination
SN - 978-989-758-402-2
AU - Oya R.
AU - Matsuoka R.
AU - Okabe T.
PY - 2020
SP - 460
EP - 465
DO - 10.5220/0009150804600465
PB - SciTePress