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Displaying 1-18 out of 18 total
Separating Reflective and Fluorescent Components Using High Frequency Illumination in the Spectral Domain
Found in: 2013 IEEE International Conference on Computer Vision (ICCV)
By Ying Fu,Antony Lam,Imari Sato,Takahiro Okabe,Yoichi Sato
Issue Date:December 2013
pp. 457-464
Hyper spectral imaging is beneficial to many applications but current methods do not consider fluorescent effects which are present in everyday items ranging from paper, to clothing, to even our food. Furthermore, everyday fluorescent items exhibit a mix o...
 
Shape Reconstruction Based on Similarity in Radiance Changes under Varying Illumination
Found in: Computer Vision, IEEE International Conference on
By Imari Sato, Takahiro Okabe, Qiong Yu, Yoichi Sato
Issue Date:October 2007
pp. 1-8
This paper presents a technique for determining an object's shape based on the similarity of radiance changes observed at points on its surface under varying illumination. To examine the similarity, we use an observation vector that represents a sequence o...
 
Robust Content-Dependent Photometric Projector Compensation
Found in: Computer Vision and Pattern Recognition Workshop
By Mark Ashdown, Takahiro Okabe, Imari Sato, Yoichi Sato
Issue Date:June 2006
pp. 6
We wish to compensate for irregularities in the output of digital projectors that occur when they are used in non-ideal situations, such as those with varying surface reflectance and ambient light. We transform the image to be displayed into a compensation...
 
Using Extended Light Sources for Modeling Object Appearance under Varying Illumination
Found in: Computer Vision, IEEE International Conference on
By Imari Sato, Takahiro Okabe, Yoichi Sato, Katsushi Ikeuchi
Issue Date:October 2005
pp. 325-332
In this study, we demonstrate the effectiveness of using extended light sources for modeling the appearance of an object for varying illumination. Extended light sources have a radiance distribution that is similar to that of the Gaussian function and have...
 
Radiometric Compensation in a Projector-Camera System Based Properties of Human Vision System
Found in: Computer Vision and Pattern Recognition Workshop
By Dong Wang, Imari Sato, Takahiro Okabe, Yoichi Sato
Issue Date:June 2005
pp. 100
<p>We introduce a novel technique for performing radiometric compensation for a projector-camera system that projects images onto a textured planar surface, which is designed to minimize perceptual artifacts visible to observers according to a model ...
 
Spherical Harmonics vs. Haar Wavelets: Basis for Recovering Illumination from Cast Shadows
Found in: Computer Vision and Pattern Recognition, IEEE Computer Society Conference on
By Takahiro Okabe, Imari Sato, Yoichi Sato
Issue Date:July 2004
pp. 50-57
The problem of estimating an illumination distribution from images is called inverse lighting. For inverse lighting, three approaches have been developed based on specular reflection components, diffuse reflection components, and cast shadows. The present ...
 
Appearance Sampling for Obtaining A Set of Basis Images for Variable Illumination
Found in: Computer Vision, IEEE International Conference on
By Imari Sato, Takahiro Okabe, Yoichi Sato, Katsushi Ikeuchi
Issue Date:October 2003
pp. 800
Previous studies have demonstrated that the appearance of an object under varying illumination conditions can be represented by a low-dimensional linear subspace. A set of basis images spanning such a linear subspace can be obtained by applying the princip...
 
Illumination from Shadows
Found in: IEEE Transactions on Pattern Analysis and Machine Intelligence
By Imari Sato, Yoichi Sato, Katsushi Ikeuchi
Issue Date:March 2003
pp. 290-300
<p><b>Abstract</b>—In this paper, we introduce a method for recovering an illumination distribution of a scene from image brightness inside shadows cast by an object of known shape in the scene. In a natural illumination condition, a scen...
 
Stability Issues in Recovering Illumination Distribution from Brightness in Shadows
Found in: Computer Vision and Pattern Recognition, IEEE Computer Society Conference on
By Imari Sato, Yoichi Sato, Katsushi Ikeuchi
Issue Date:December 2001
pp. 400
This paper describes a robust method for estimating, in a reliable manner, the illumination distribution of a real scene from shadows in a given image. In general, shadows in a scene are caused by the occlusion of incoming light; image brightness inside sh...
 
Illumination Distribution from Brightness in Shadows: Adaptive Estimation of Illumination Distribution with Unknown Reflectance Properties in Shadow Regions
Found in: Computer Vision, IEEE International Conference on
By Imari Sato, Yoichi Sato, Katsushi Ikeuchi
Issue Date:September 1999
pp. 875
This paper describes a new method for estimating the illumination distribution of a real scene from a radiance distribution inside shadows cast by an object in the scene. First, the illumination distribution of the scene is approximated by discrete samplin...
 
Illumination Distribution from Shadows
Found in: Computer Vision and Pattern Recognition, IEEE Computer Society Conference on
By Imari Sato, Yoichi Sato, Katsushi Ikeuchi
Issue Date:June 1999
pp. 1306
The image irradiance of a three-dimensional object is known to be the function of three components: the distribution of light sources, the shape, and reflectance of a real object surface. In the past, recovering the shape and reflectance of an object surfa...
 
Acquiring a Radiance Distribution to Superimpose Virtual Objects onto a Real Scene
Found in: IEEE Transactions on Visualization and Computer Graphics
By Imari Sato, Yoichi Sato, Katsushi Ikeuchi
Issue Date:January 1999
pp. 1-12
<p><b>Abstract</b>—This paper describes a new method for superimposing virtual objects with correct shadings onto an image of a real scene. Unlike the previously proposed methods, our method can measure a radiance distribution of a real s...
 
3D shape and reflectance morphing
Found in: Shape Modeling and Applications, International Conference on
By Yoichi Sato, Imari Sato, Katsushi Ikeuchi
Issue Date:March 1997
pp. 234
This paper describes a new method for 3D shape and reflectance morphing of two real 3D objects. Our morphing method consists of two components: shape and reflectance property measurement, and smooth interpolation of those measured properties. Unlike other ...
 
BRDF Estimation of Structural Color Object by Using Hyper Spectral Image
Found in: 2013 IEEE International Conference on Computer Vision Workshops (ICCVW)
By Yoshie Kobayashi,Tetsuro Morimoto,Imari Sato,Yasuhiro Mukaigawa,Katsushi Ikeuchi
Issue Date:December 2013
pp. 915-922
In computer graphics, there are several methods to render thin film interference effects, but it sets the parameters of interference manually. To reconstruct more accurate appearance of the thin film, we need to estimate the BRDF parameters of the thin fil...
 
Image-Based Separation of Reflective and Fluorescent Components Using Illumination Variant and Invariant Color
Found in: IEEE Transactions on Pattern Analysis and Machine Intelligence
By Cherry Zhang,Imari Sato
Issue Date:December 2013
pp. 2866-2877
Traditionally, researchers tend to exclude fluorescence from color appearance algorithms in computer vision and image processing because of its complexity. In reality, fluorescence is a very common phenomenon observed in many objects, from gems and corals,...
 
Uncalibrated Photometric Stereo for Unknown Isotropic Reflectances
Found in: 2013 IEEE Conference on Computer Vision and Pattern Recognition (CVPR)
By Feng Lu,Yasuyuki Matsushita,Imari Sato,Takahiro Okabe,Yoichi Sato
Issue Date:June 2013
pp. 1490-1497
We propose an uncalibrated photometric stereo method that works with general and unknown isotropic reflectances. Our method uses a pixel intensity profile, which is a sequence of radiance intensities recorded at a pixel across multi-illuminance images. We ...
 
Spectral Modeling and Relighting of Reflective-Fluorescent Scenes
Found in: 2013 IEEE Conference on Computer Vision and Pattern Recognition (CVPR)
By Antony Lam,Imari Sato
Issue Date:June 2013
pp. 1452-1459
Hyper spectral reflectance data allows for highly accurate spectral relighting under arbitrary illumination, which is invaluable to applications ranging from archiving cultural e-heritage to consumer product design. Past methods for capturing the spectral ...
 
Sensation-based photo cropping
Found in: Proceedings of the seventeen ACM international conference on Multimedia (MM '09)
By Imari Sato, Masashi Nishiyama, Takahiro Okabe, Yoichi Sato
Issue Date:October 2009
pp. 669-672
This paper proposes a novel method for automatically cropping a photo using a quality classifier that assesses whether the cropped region is agreeable to users. We statistically build this quality classifier using large photo collections available on websi...
     
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