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41
Photorealistic Scene Reconstruction by Voxel Coloring
, 1997
"... A novel scene reconstruction technique is presented, different from previous approaches in its ability to cope with large changes in visibility and its modeling of intrinsic scene color and texture information. The method avoids image correspondence problems by working in a discretized scene space w ..."
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Cited by 411 (20 self)
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A novel scene reconstruction technique is presented, different from previous approaches in its ability to cope with large changes in visibility and its modeling of intrinsic scene color and texture information. The method avoids image correspondence problems by working in a discretized scene space whose voxels are traversed in a fixed visibility ordering. This strategy takes full account of occlusions and allows the input cameras to be far apart and widely distributed about the environment. The algorithm identifies a special set of invariant voxels which together form a spatial and photometric reconstruction of the scene, fully consistent with the input images.
Separation of reflection components using color and polarization
 IJCV
, 1997
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A Theory of Specular Surface Geometry
, 1996
"... A theoretical framework is introduced for the perception of specular surface geometry. When an observer moves in threedimensional space, real scene features such as surface markings remain stationary with respect to the surfaces they belong to. In contrast, a virtual feature which is the specular r ..."
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Cited by 78 (2 self)
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A theoretical framework is introduced for the perception of specular surface geometry. When an observer moves in threedimensional space, real scene features such as surface markings remain stationary with respect to the surfaces they belong to. In contrast, a virtual feature which is the specular reflection of a real feature, travels on the surface. Based on the notion of caustics, a feature classification algorithm is developed that distinguishes real and virtual features from their image trajectories that result from observer motion. Next, using support functions of curves, a closedform relation is derived between the image trajectory of a virtual feature and the geometry of the specular surface it travels on. It is shown that, in the 2D case, where camera motion and the surface profile are coplanar, the profile is uniquely recovered by tracking just two unknown virtual features. Finally, these results are generalized to the case of arbitrary 3D surface profiles that are traveled by virtual features when camera motion is not confined to a plane. This generalization includes a number of mathematical results that substantially enhance the present understanding of specular surface geometry. An algorithm is developed that uniquely recovers 3D surface profiles using a single virtual feature tracked from the occluding boundary of the object. All theoretical derivations and proposed algorithms are substantiated by experiments.
Multiview Stereo Beyond Lambert
 In International Conference on Computer Vision and Pattern Recognition
, 2002
"... We consider the problem of estimating the shape and radiance of an object from a calibrated set of views under the assumption that the reflectance of the object is nonLambertian. Unlike traditional stereo, we do not solve the correspondence problem by comparing imagetoimage. Instead, we exploit a ..."
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Cited by 52 (8 self)
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We consider the problem of estimating the shape and radiance of an object from a calibrated set of views under the assumption that the reflectance of the object is nonLambertian. Unlike traditional stereo, we do not solve the correspondence problem by comparing imagetoimage. Instead, we exploit a rank constraint on the radiance tensor field of the surface in space, and use it to define a discrepancy measure between each image and the underlying model. Our approach automatically returns an estimate of the radiance of the scene, along with its shape, represented by a dense surface. The former can be used to generate novel views that capture the nonLambertian appearance of the scene.
Separating Reflections from Images Using Independent Components Analysis
 Journal of the Optical Society of America
, 1998
"... this paper describes a method for photographing objects behind glass and digitally removing the reflections off the glass leaving the image of the objects behind the glass intact. We describe the details of this method which employssimple optical techniques and independent components analysis (ICA) ..."
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Cited by 52 (3 self)
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this paper describes a method for photographing objects behind glass and digitally removing the reflections off the glass leaving the image of the objects behind the glass intact. We describe the details of this method which employssimple optical techniques and independent components analysis (ICA) and show its efficacy with several examples. 1 Introduction
Multiview stereo reconstruction of dense shape and complex appearance
 The International Journal of Computer Vision
, 2005
"... appearance models. ..."
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Stereo in the Presence of Specular Reflection
 IN ICCV
, 1995
"... The problem of accurate depth estimation using stereo in the presence of specular reflection is addressed. Specular reflection is viewpoint dependent and can cause large intensity differences at corresponding points. Hence, mismatches can result causing significant depth errors. Current stereo algor ..."
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Cited by 27 (1 self)
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The problem of accurate depth estimation using stereo in the presence of specular reflection is addressed. Specular reflection is viewpoint dependent and can cause large intensity differences at corresponding points. Hence, mismatches can result causing significant depth errors. Current stereo algorithms largely ignore specular reflection which is a fundamental reflection phenomenon from surfaces, both smooth and rough. We analyzed the physics of specular reflection and the geometry of stereopsis which led us to an interesting relationship between stereo vergence, surface roughness, and the likelihood of a correct match. Given the lower bound on surface roughness, an optimal binocular stereo configuration can be determined which maximizes precision in depth estimation despite specular reflection. However, surface roughness is difficult to estimate in unstructured environments. Therefore, multiple view configurations independent of surface roughness are determined such that at each scen...
Separating Reflections and Lighting Using Independent Components Analysis
, 1999
"... The image of an object can vary dramatically depending on lighting, specularities/reflections and shadows. It is often advantageous to separate these incidental variations from the intrinsic aspects of an image. This paper describes how the statistical tool of independent components analysis can be ..."
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Cited by 25 (0 self)
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The image of an object can vary dramatically depending on lighting, specularities/reflections and shadows. It is often advantageous to separate these incidental variations from the intrinsic aspects of an image. This paper describes how the statistical tool of independent components analysis can be used to separate some of these incidental components. We describe the details of this method and show its efficacy with examples of separating reflections off glass, and separating the relative contributions of individual light sources.
Stereo and Specular Reflection
 IJCV
, 1998
"... . The problem of accurate depth estimation using stereo in the presence of specular reflection is addressed. Specular reflection, a fundamental and ubiquitous reflection mechanism, is viewpoint dependent and can cause large intensity differences at corresponding points, resulting in significant dept ..."
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Cited by 23 (2 self)
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. The problem of accurate depth estimation using stereo in the presence of specular reflection is addressed. Specular reflection, a fundamental and ubiquitous reflection mechanism, is viewpoint dependent and can cause large intensity differences at corresponding points, resulting in significant depth errors. We analyze the physics of specular reflection and the geometry of stereopsis which lead to a relationship between stereo vergence, surface roughness, and the likelihood of a correct match. Given a lower bound on surface roughness, an optimal binocular stereo configuration can be determined which maximizes precision in depth estimation despite specular reflection. However, surface roughness is difficult to estimate in unstructured environments. Therefore, trinocular configurations, independent of surface roughness, are determined such that at each scene point visible to all sensors, at least one stereo pair can produce correct depth. We have developed a simple algorithm to reconstru...
BRDF invariant stereo using light transport constancy
 In ICCV 05
, 2005
"... Nearly all existing methods for stereo reconstruction assume that scene reflectance is Lambertian, and make use of color constancy as a matching invariant. We introduce a new invariant for stereo reconstruction called Light Transport Constancy, which allows completely arbitrary scene reflectance (BR ..."
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Cited by 19 (1 self)
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Nearly all existing methods for stereo reconstruction assume that scene reflectance is Lambertian, and make use of color constancy as a matching invariant. We introduce a new invariant for stereo reconstruction called Light Transport Constancy, which allows completely arbitrary scene reflectance (BRDFs). This invariant can be used to formulate a rank constraint on multiview stereo matching when the scene is observed in several lighting configurations. In addition, we show that this multiview constraint can be used with as few as two cameras and two lighting configurations. Unlikely previous methods for BRDF invariant stereo, Light Transport Constancy does not require precisely configured or calibrated light sources, nor calibration objects in the scene. Importantly, the new constraint can be used to provide BRDF invariance to any existing stereo method, whenever appropriate lighting variation is available. 1.