Garcia-Diaz Antón, Leborán Víctor, Fdez-Vidal Xosé R, Pardo Xosé M
Computer Vision Group, University of Santiago de Compostela, Galicia, Spain.
J Vis. 2012 Jun 12;12(6):17. doi: 10.1167/12.6.17.
A 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 movements.
本文提出了一种光学变异性的层次定义，该定义将物理量与视觉显著性联系起来，并且比以往的方法产生了更简化的解释。事实证明，这一定义基于经典的高效编码假设。此外，我们提出，上下文适应机制的一个主要目标是确保图像点对光学变异性的贡献在视觉系统中引发的行为的不变性。通过与人类注视点以及三个开放获取的眼动追踪数据集中的显著性最新方法进行比较，对这一假设和必要假设进行了测试，其中一个数据集专门用于面部图像，同时还进行了一项使用表面反射率的高光谱表示的新实验。与之前的研究相比，面部图像的结果显著降低了语义影响的潜在强度。高光谱图像的结果支持了估计光学变异性的假设。同样，所提出的方法解释了与观察到的角落图像视觉错觉相关的定量结果，该错觉不涉及眼球运动。
