García Díaz, AntónLeborán Álvarez, VíctorFernández Vidal, Xosé RamónPardo López, Xosé Manuel2020-04-082020-04-082012Garcia-Diaz, A., Leborán, V., Fdez-Vidal, X. R., & Pardo, X. M. (2012). On the relationship between optical variability, visual saliency, and eye fixations: A computational approach. Journal of Vision, 12(6):17, 1–22, http://www. journalofvision.org/content/12/6/17, doi:10.1167/12.6.17http://hdl.handle.net/10347/21259A hierarchical definition of optical variability is proposed that links physical magnitudes to visual saliency and yields a more reductionist interpretation than previous approaches. This definition is shown to be grounded on the classical efficient coding hypothesis. Moreover, we propose that a major goal of contextual adaptation mechanisms is to ensure the invariance of the behavior that the contribution of an image point to optical variability elicits in the visual system. This hypothesis and the necessary assumptions are tested through the comparison with human fixations and state-of-the-art approaches to saliency in three open access eye-tracking datasets, including one devoted to images with faces, as well as in a novel experiment using hyperspectral representations of surface reflectance. The results on faces yield a significant reduction of the potential strength of semantic influences compared to previous works. The results on hyperspectral images support the assumptions to estimate optical variability. As well, the proposed approach explains quantitative results related to a visual illusion observed for images of corners, which does not involve eye movementseng© 2019 ARVO. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) license (https://creativecommons.org/licenses/by-nc-nd/4.0/)https://creativecommons.org/licenses/by-nc-nd/4.0/Optical variabilityContextual adaptationSaliencyEfficient codingEye fixationsFace saliencyHyperspectraljournal article10.1167/12.6.171534-7362open access