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Measuring the Light Reflectance with Mobile Devices

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Abstract

In this article, we propose a methodology to measure the light reflectance of the material surface using a simple hardware set-up consisting of generally available mobile phones. The designed method incorporates two mobile phones to facilitate a time-consuming procedure. One device serves us as the light source and second one as the detector aperture. The user will move two phones with two hands above a measured sample, and the method will take into account only the correctly captured images. In this work, we propose a method to estimate the view direction of a phone camera and light source. A subsequent problem we solve is the fast Wi-Fi Direct device communication. We outline the enumeration of the bidirectional reflectance distribution function (BRDF) from the light intensities reflected off the planar samples. We present the satisfactory results measured with mobile phone cameras in a casual environment.

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Metallic paint appearance measurement and rendering
  • Matusik
Matusik et al., 2003. Matusik, W., Pfister, H., Brand, M., and McMillan, L. (2003). A data-driven reflectance model. In SIGGRAPH '03: ACM SIGGRAPH 2003 Papers, pages 759-769, New York, NY, USA. ACM. Medioni and Kang, 2004. Medioni, G. and Kang, S. B. (2004). Emerging Topics in Computer Vision. Prentice Hall PTR, Upper Saddle River, NJ, USA. Mihálik andˇDurikovičandˇ andˇDurikovič, 2013. Mihálik, A. andˇDurikovičandˇ andˇDurikovič, R. (2013). Metallic paint appearance measurement and rendering. Journal of the Applied Mathematics, Statistics and Informatics, 9(2):25-39.
Metallic paint appearance measurement and rendering
  • Mihálik
  • A Mihálik
  • R Andďurikovič
Mihálik andĎurikovič, 2013. Mihálik, A. andĎurikovič, R. (2013). Metallic paint appearance measurement and rendering. Journal of the Applied Mathematics, Statistics and Informatics, 9(2):25-39.