Results 131 to 140 of about 1,126 (166)
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ShadowCuts: Photometric Stereo with Shadows
2007 IEEE Conference on Computer Vision and Pattern Recognition, 2007We present an algorithm for performing Lambertian photometric stereo in the presence of shadows. The algorithm has three novel features. First, a fast graph cuts based method is used to estimate per pixel light source visibility. Second, it allows images to be acquired with multiple illuminants, and there can be fewer images than light sources.
Manmohan Krishna Chandraker +2 more
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Recognition of polyhedra by photometric stereo
1989This paper describes an image segmentation and analysis technique based on three-dimensional information gathered by means of the stereo-photometric approach. It allows the measure of the attitude and area of surfaces whose optical properties are known.
Luigi Carrioli, Ugo Cei, Marco Diani
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Deep Photometric Stereo Network
2017 IEEE International Conference on Computer Vision Workshops (ICCVW), 2017This paper presents a photometric stereo method based on deep learning. One of the major difficulties in photometric stereo is designing can appropriate reflectance model that is both capable of representing real-world reflectances and computationally tractable in terms of deriving surface normal. Unlike previous photometric stereo methods that rely on
Hiroaki Santo +4 more
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Resolution-Enhanced Photometric Stereo
2006Conventional photometric stereo has a fundamental limitation that the scale of recovered geometry is limited to the resolution of the input images. However, surfaces that contain sub-pixel geometric structures are not well modelled by a single normal direction per pixel.
Ping Tan 0002 +2 more
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Base Materials for Photometric Stereo
2012Image-based capture of material appearance has been extensively studied, but the quality of the results and generality of the applied methods leave a lot of room for improvement. Most existing methods rely on parametric models of reflectance and require complex hardware systems or accurate geometric models that are not always available or practical ...
David Tingdahl +2 more
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2010
We propose a novel algorithm for uncalibrated photometric stereo. While most of previous methods rely on various assumptions on scene properties, we exploit constraints in lighting configurations. We first derive an ambiguous reconstruction by requiring lights to lie on a view centered cone.
Zhenglong Zhou, Ping Tan
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We propose a novel algorithm for uncalibrated photometric stereo. While most of previous methods rely on various assumptions on scene properties, we exploit constraints in lighting configurations. We first derive an ambiguous reconstruction by requiring lights to lie on a view centered cone.
Zhenglong Zhou, Ping Tan
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Time‐Lapse Photometric Stereo and Applications
Computer Graphics Forum, 2014AbstractThis paper presents a technique to recover geometry from time‐lapse sequences of outdoor scenes. We build upon photometric stereo techniques to recover approximate shadowing, shading and normal components allowing us to alter the material and normals of the scene. Previous work in analyzing such images has faced two fundamental difficulties: 1.
Fangyang Shen +5 more
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Photometric Stereo via Expectation Maximization
IEEE Transactions on Pattern Analysis and Machine Intelligence, 2010This paper presents a robust and automatic approach to photometric stereo, where the two main components, namely surface normals and visible surfaces, are respectively optimized by Expectation Maximization (EM). A dense set of input images is conveniently captured using a digital video camera while a handheld spotlight is being moved around the target ...
Wu, Tai-Pang, Tang, Chi-Keung
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Binocular Uncalibrated Photometric Stereo
2006In Uncalibrated Photometric Stereo (UPS), the surface normals and light sources are determined up to a group of ambiguous Generalized Bas-Relief (GBR) transformations. However, it has been shown by previous works to be rather troublesome to solve these ambiguities. In this paper, a framework of Binocular Uncalibrated Photometric Stereo (B-UPS) is given
Hui Kong 0001 +2 more
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A new approach to photometric stereo
Pattern Recognition Letters, 1999Abstract We introduce a new approach to shape estimation from photometric stereo images. The input images are matched through an optical flow algorithm, with the matching direction iteratively refined. The resulting disparity field is then used in a structure-from-motion reconstruction which does not require reflectance map information.
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