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Geometric Point Light Source Calibration
"... We present a light position calibration technique based on a general arrangement of at least two reflective spheres in a single image. Contrary to other techniques we do not directly intersect rays for triangulation but instead solve for the optimal light position by evaluating the imagespace error ..."
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space error of the light highlights reflected from the spheres. This approach has been very successful in the field of StructurefromMotion estimation. It has not been applied to light source calibration because determining the reflection point on the sphere to project the highlight back in the image is a
Photometric Linearization under Near Point Light Sources
"... We present a method for generating linearized images that consist of onlydiffuse reflection from images taken under near point light sources.Previous photometriclinearization method cannot work under near point light sources,since it assumes parallel light. For satisfying this assumption,our method ..."
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We present a method for generating linearized images that consist of onlydiffuse reflection from images taken under near point light sources.Previous photometriclinearization method cannot work under near point light sources,since it assumes parallel light. For satisfying this assumption,our method
The geometry of point light source from shadows
, 2004
"... Shadows provide valuable information about the scene geometry, especially the whereabout of the light source. This paper investigates the geometry of point light sources and cast shadows. It is known that there is redundancy in the objectshadow correspondences. We explicitly show that no matter h ..."
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Cited by 1 (1 self)
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Shadows provide valuable information about the scene geometry, especially the whereabout of the light source. This paper investigates the geometry of point light sources and cast shadows. It is known that there is redundancy in the objectshadow correspondences. We explicitly show that no matter
A Practical Method for Estimation of Point LightSources
 PROCEEDINGS BMVC 2001
, 2001
"... We introduce a general model for point lightsources and show how the parameters of a source at finite distance can be estimated by shading on an object with known geometry and Lambertian reflectance. The parameters we estimate include not only the direction but also the location of the source. Furt ..."
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Cited by 9 (2 self)
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We introduce a general model for point lightsources and show how the parameters of a source at finite distance can be estimated by shading on an object with known geometry and Lambertian reflectance. The parameters we estimate include not only the direction but also the location of the source
Performance Analysis of Point Light Source Estimation
, 1999
"... In this paper, the performance of point light source parameter estimation from two video images is analyzed in terms of estimation theory. The illumination parameters are the intensity and direction of a single distant point light source in presence of ambient light. Known illumination estimation me ..."
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In this paper, the performance of point light source parameter estimation from two video images is analyzed in terms of estimation theory. The illumination parameters are the intensity and direction of a single distant point light source in presence of ambient light. Known illumination estimation
A Practical Method for Estimation of Point LightSources
 proceedings BMVC 2001
, 2001
"... We introduce a general model for point lightsources and show how the parameters of a source at finite distance can be estimated by shading on an object with known geometry and Lambertian reflectance. The parameters we estimate include not only the direction but also the location of the source. Furt ..."
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We introduce a general model for point lightsources and show how the parameters of a source at finite distance can be estimated by shading on an object with known geometry and Lambertian reflectance. The parameters we estimate include not only the direction but also the location of the source
Illuminating The Free Space Between Quadrilaterals With Point Light Sources
 PROC. COMPUTER GRAPHICS INT.,. WORLD SCIENTIFIC
, 1994
"... Let S be a set of n pairwisedisjoint, possibly nonconvex, quadrilaterals in the plane. We consider the problem of illuminating the "free" space, i.e., the region of the plane excluding the interiors of the quadrilaterals (which act as barriers), by using point light sources. We show that ..."
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Cited by 3 (0 self)
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Let S be a set of n pairwisedisjoint, possibly nonconvex, quadrilaterals in the plane. We consider the problem of illuminating the "free" space, i.e., the region of the plane excluding the interiors of the quadrilaterals (which act as barriers), by using point light sources. We show
Calibrating a Nonisotropic Near Point Light Source using a Plane
"... We show that a nonisotropic near point light source rigidly attached to a camera can be calibrated using multiple images of a weakly textured planar scene. We prove that if the radiant intensity distribution (RID) of a light source is radially symmetric with respect to its dominant direction, then ..."
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Cited by 1 (1 self)
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We show that a nonisotropic near point light source rigidly attached to a camera can be calibrated using multiple images of a weakly textured planar scene. We prove that if the radiant intensity distribution (RID) of a light source is radially symmetric with respect to its dominant direction
Light Field Rendering
, 1996
"... A number of techniques have been proposed for flying through scenes by redisplaying previously rendered or digitized views. Techniques have also been proposed for interpolating between views by warping input images, using depth information or correspondences between multiple images. In this paper, w ..."
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Cited by 1354 (22 self)
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 the light field. This function completely characterizes the flow of light through unobstructed space in a static scene with fixed illumination. We describe a
Detection and Tracking of Point Features
 International Journal of Computer Vision
, 1991
"... The factorization method described in this series of reports requires an algorithm to track the motion of features in an image stream. Given the small interframe displacement made possible by the factorization approach, the best tracking method turns out to be the one proposed by Lucas and Kanade i ..."
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Cited by 622 (2 self)
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The factorization method described in this series of reports requires an algorithm to track the motion of features in an image stream. Given the small interframe displacement made possible by the factorization approach, the best tracking method turns out to be the one proposed by Lucas and Kanade in 1981. The method defines the measure of match between fixedsize feature windows in the past and current frame as the sum of squared intensity differences over the windows. The displacement is then defined as the one that minimizes this sum. For small motions, a linearization of the image intensities leads to a NewtonRaphson style minimization. In this report, after rederiving the method in a physically intuitive way, we answer the crucial question of how to choose the feature windows that are best suited for tracking. Our selection criterion is based directly on the definition of the tracking algorithm, and expresses how well a feature can be tracked. As a result, the criterion is optima...
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