Polarization is a fundamental property of light that encodes abundant information regarding surface shape, material, illumination and viewing geometry. The computer vision community has witnessed a blossom of polarization-based vision applications, such as reflection removal, shape-from-polarization, transparent object segmentation and color constancy, partially due to the emergence of single-chip mono/color polarization sensors that make polarization data acquisition easier than ever. However, is polarization-based vision vulnerable to adversarial attacks? If so, is that possible to realize these adversarial attacks in the physical world, without being perceived by human eyes? In this paper, we warn the community of the vulnerability of polarization-based vision, which can be more serious than RGB-based vision. By adapting a commercial LCD projector, we achieve locally controllable polarizing projection, which is successfully utilized to fool state-of-the-art polarization-based vision algorithms for glass segmentation and color constancy. Compared with existing physical attacks on RGB-based vision, which always suffer from the trade-off between attack efficacy and eye conceivability, the adversarial attackers based on polarizing projection are contact-free and visually imperceptible, since naked human eyes can rarely perceive the difference of viciously manipulated polarizing light and ordinary illumination. This poses unprecedented risks on polarization-based vision, both in the monochromatic and trichromatic domain, for which due attentions should be paid and counter measures be considered.

翻译：极化是光的基本特性，可编码有关表面形状、材料、照明和视角几何方面的丰富信息。由于单片彩色极化传感器的出现，计算机视觉社区见证了基于极化的视觉应用的蓬勃发展，例如去反射、极化形状、透明物体分割和色彩恒定性。然而，基于极化的视觉是否容易受到对抗性攻击？如果是，那么是否可以在不被人眼察觉的情况下在物理世界中实现这些对抗性攻击？ 本文警告社区极化视觉的易受攻击性，这可能比基于RGB的视觉更严重。通过采用商业液晶投影仪，我们实现了局部可控偏振投影，成功利用于欺骗最先进的极化分割算法和色彩恒定性算法。与现有基于RGB的视觉攻击不同的是，基于偏振投影的对抗攻击是无接触和视觉上不可感知的，因为裸眼不能区分经过恶意操作的偏振光和普通照明的区别。这给极化视觉带来了前所未有的风险，在单色和三色领域都存在风险，需要引起足够的注意，考虑防御措施。