Surface color perception and illuminant cues in dynamic three-dimensional scenes

人类视觉最令人印象深刻的方面之一是表面颜色在非常不同的照明条件下的稳定性。视觉系统非常善于将照明的颜色从表面的实际颜色中分离出来，工程师目前还无法制造出与人类性能相匹配的摄像头。大多数以前的研究都集中在非常简单的刺激上，这些刺激由在漫反射(均匀)照明下排列在平板上的少量平坦的彩色表面组成。这项拟议的研究利用计算机图形学的最新进展来创建物理上准确的虚拟场景，其中填充了许多不同深度和方向的对象，这些对象由逼真的日光光源照明，模仿太阳、天空和云层的效果。在这样的场景中，视觉系统面临的主要挑战是照明很少是均匀的。在这里提出的这项研究中，研究人员将分析视觉系统如何使用关于照明条件(如表面阴影和高光)的简单“线索”来估计稳定的表面颜色。眼球跟踪技术的使用使实验者能够监控观察者在收集有关场景照明条件的信息时看向哪里。这项研究首次使用眼球跟踪技术来研究物体的表面颜色感知。人类将稳定的表面颜色和稳定的形状赋予物体的能力是一项非凡的成就。这项研究将有助于更好地理解大脑如何自适应地利用场景中有关深度和颜色的信息来源，从而更好地理解大脑对损伤、疾病甚至正常衰老的反应。此外，对大脑如何利用线索进行场景布局和照明的研究，可以为复制生物功能的人工视觉系统的产生提供信息。表面颜色的细微变化伴随着植物和动物的许多疾病状态，这种系统将在遥感方面有明显的应用，从监测作物到早期发现疾病。

One of the most impressive aspects of human vision is the stability of surface colors under very different lighting conditions. The visual system is remarkably good at separating the color of the illumination from the actual colors of surfaces and engineers are not currently able to build a camera that can match human performance. Most previous research has focused on very simple stimuli consisting of a small number of flat colored surfaces arranged on a flat panel under diffuse (uniform) lighting. The proposed research makes use of recent advances in computer graphics to create physically-accurate virtual scenes filled with objects at many different depths and orientations illuminated by realistic daylight illuminants mimicking the effects of sun, sky and cloud cover. The major challenge for the visual system in such scenes is that illumination is rarely uniform. In the research proposed here, the investigator will analyze how the visual system uses simple "cues" about illumination conditions such as surface shading and highlights to estimate stable surface colors. The use of eye tracking technology allows the experimenter to monitor where the observer looks in gathering information about the conditions of scene illumination. The proposed research represents the first use of eye-tracking technology to study surface color perception.The human ability to assign stable surface colors and stable shapes to objects is an extraordinary achievement. This research will lead to a better understanding of how the brain adaptively makes use of sources of information about depth and color in scenes which, in turn, will provide a better understanding of how the brain reacts to injury, disease and even normal aging. Moreover, research on how the brain uses cues to scene layout and lighting can inform the production of artificial visual systems that duplicate biological function. Subtle changes in surface color accompany many disease states in plant and animal and such systems would have evident applications in remote sensing, from monitoring crops to early detection of illness.