Scott Wehrwein

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We present a method for computing ambient occlusion (AO) for a stack of images of a scene from a fixed viewpoint. Ambient occlusion, a concept common in computer graphics, characterizes the local visibility at a point: it approximates how much light can reach that point from different directions without getting blocked by other geometry. While AO has(More)
This paper presents the Static Computational Optical Undersampled Tracker (SCOUT), an architecture for compressive motion tracking systems. The architecture uses compressive sensing techniques to track moving targets at significantly higher resolution than the detector array, allowing for low cost, low weight design and a significant reduction in data(More)
Natural illumination from the sun and sky plays a significant role in the appearance of outdoor scenes. We propose the use of sophisticated outdoor illumination models, developed in the computer graphics community, for estimating appearance and timestamps from a large set of uncalibrated images of an outdoor scene. We first present an analysis of the(More)
Modeling the appearance of outdoor scenes from photo collections is challenging because of appearance variation, especially due to illumination. In this paper we present a simple and robust algorithm for estimating illumination properties-shadows and sun direction-from photo collections. These properties are key to a variety of scene modeling applications,(More)
Many of today’s most successful video segmentation methods use long-term feature trajectories as their first processing step. Such methods typically use spectral clustering to segment these trajectories, implicitly assuming that motion is translational in image space. In this paper, we explore the idea of explicitly fitting more general motion models in(More)
We present a method for computing ambient occlusion (AO) for a stack of images of a Lambertian scene from a fixed viewpoint. Ambient occlusion, a concept common in computer graphics, characterizes the local visibility at a point: it approximates how much light can reach that point from different directions without getting blocked by other geometry. While AO(More)
Algorithm 1 gives the procedure used to optimize the background motion model as described in Section 4. GetWeights computes the residuals from the given model Hk and uses Equation 3 to compute the weight for each track in T . Similarly, GetCost computes the total cost (Equation 4). Finally, WLS uses a weighted-least-squares variant of the four-point(More)
The tools for capturing and sharing photos and videos have exploded to the point of ubiquity. Internet photo collections of popular landmarks now contain over a decade’s worth of photographs; thousands of timelapse scenes are available on video sharing websites; live cameras stream real-time videos of many scenes 24 hours a day; high-resolution images of an(More)
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