RI: Toward Shape from Specular Reflections under Real-world Illumination

提案0712956 PI：托德·齐克勒研究所：哈佛大学题目：RI：从现实世界照明下的镜面反射走向形状摘要：从图像数据中恢复形状信息是计算机视觉中的一个中心问题，几十年的研究已经导致了用于从包括阴影、纹理、颜色和阴影在内的各种视觉线索推断形状的计算工具的开发。形状的一个重要视觉提示是镜面反射。镜面(镜面)在自然和人造环境中都很丰富。金属、玻璃、池塘的波浪形表面和釉面陶瓷就是几个例子。镜面将入射光反射到观察者身上而不会衰减，当镜面被弯曲时，它们呈现出其照明环境的扭曲版本，其中包含关于其形状的非常丰富的信息。虽然知觉研究表明人类利用这种视觉线索，但潜在的机制尚不清楚，还不存在从现实世界照明下的镜面反射推断形状的计算工具。相反，由于镜面形状及其图像之间关系的复杂性，以前的分析仅限于受控的、非自然的环境和/或非常有限的表面类型。此建议通过特别考虑不受控制的真实世界照明条件下的任意平滑曲面，朝着根本不同的方向移动。这一看似困难的任务可以通过一种新的方法来处理，该方法包括两个关键部分：1)考虑环境-表面距离相对于表面起伏较大的远场照明环境；以及2)“镜面流”-由镜面与其环境之间的相对运动引起的图像平面上的密集运动场的分析。这种方法在易操纵性和实际有效性之间提供了独特的平衡，它可能是促进我们对强大视觉提示的理解的关键一步。该项目的进展报告将定期更新，网址为http：\\www.eecs.finard.edu\~Zickler

Proposal 0712956 PI: Todd ZicklerInstitution: Harvard UniversityTitle: RI: Toward Shape from Specular Reflections under Real-world IlluminationAbstract:The recovery of shape information from image data is a central problem in computer vision, and decades of research have led to the development of computational tools for inferring shape from a variety of visual cues, including shading, texture, color, and shadows. An important visual cue for shape is specular reflection. Specular(mirror-like) surfaces are abundant in both natural and man-made environments. Metal, glass, the wavy surface of a pond, and glazed ceramics are a few examples. Specular surfaces reflect incident light toward an observer without attenuation, and when they are curved, they present a distorted version of their illumination environment that contains very rich information about their shape. While perceptual studies suggest that humans make use of this visual cue, the underlying mechanisms are not yet known, and computational tools for inferring shape from specular reflections under real-world illumination do not yet exist. Instead, due to the complexity of the relationship between a specular shape and its images, previous analysis has been limited to controlled, unnatural environments and/or very limited types of surfaces. This proposal moves in a fundamentally different direction by specifically considering arbitrary smooth surfaces in uncontrolled, real-world illumination conditions. This seemingly difficult task is made manageable by a novel approach with two key components: 1) the consideration of far-field illumination environments in which the environment-surface distance is large relative to the relief of the surface; and 2) the analysis of ``specular flow''---the dense motion field on the image plane that is induced by the relative movement between a specular surface and its environment. This approach provides a unique balance between tractability and practical validity, and it may be a pivotal step in furthering our understanding of a powerful visual cue.Progress reports for this project will be regularly updated at http:\\www.eecs.harvard.edu\~zickler