担当区分：最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

Outdoor shadows can be classified into two categories: continuous shadows caused by static objects and momentary shadows caused by moving objects. Since the momentary shadows such as shadows due to a photographer are annoying and do not exist in the original scene, they should be detected and removed for improving image quality. In this paper, we propose a method for detecting momentary shadows from a visible and thermal image pair. The key idea of our proposed method is that the continuous shadows have lower temperature than non-shadow areas, while the momentary shadows have almost the same temperature as the non-shadow areas. Therefore, our method combines the shadow areas detected by using an RGB image and the higher-temperature areas detected by using a thermal image, and then detects the areas of momentary shadows via image segmentation. Through a number of experiments using real visible and thermal image pairs, we show that the combination of visible and thermal images are effective for detecting momentary shadows, and that our method works well for momentary shadows with varying duration time.

DOI： 10.23919/EUSIPCO54536.2021.9615977

Scopus

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担当区分：最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

Water and oil detection is important for machine vision applications such as visual inspection and robot motion planning. It is known that water absorbs near infrared light and oil absorbs near ultraviolet and blue light. Therefore, observing at the absorbed wavelengths, the apparent spectral reflectances of surfaces with water/oil are smaller than that without water/oil. We could detect water/oil based on the above absorption features by using a hyperspectral image, if the original spectral reflectances of surfaces are known. However, in general, the spectral reflectances of surfaces are unknown and spatially varying. In this paper, we propose a novel per-pixel water and oil detection method based on the Lambert-Beer's law and a low-dimensional linear model for spectral reflectance. We show that our method enables us to pixelwisely detect water and oil on surfaces with unknown and spatially-varying reflectance at high accuracy by using a hyperspectral image. The effectiveness of our proposed method is confirmed through a number of experiments using real hyperspectral images.

DOI： 10.23919/EUSIPCO54536.2021.9616011

Scopus

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

Measuring per-pixel surface roughness is useful for machine vision applications such as visual inspection. The surface roughness can be recovered from specular reflection components, but a large number of images taken under different lighting and/or viewing directions is required in general so that sufficient specular reflection components are observed at each pixel. In this paper, we propose a robust and efficient method for per-pixel estimation of surface roughness. Specifically, we propose an illumination planning based on noise propagation analysis; it achieves the surface roughness estimation from a small number of images taken under the optimal set of light sources. Through the experiments using both synthetic and real images, we experimentally show the effectiveness of our proposed method and our setup with a programmable illumination and a polarization camera.

DOI： 10.23919/MVA51890.2021.9511392

Scopus

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

In this paper, we propose a method for fast separation of specular, diffuse, and global components of a dynamic scene by using a projector-camera system. Both the direct-global separation using spatially high-frequency patterns and the specular-diffuse separation based on polarization have been studied, but a straightforward combination of those methods has limited temporal resolution. Accordingly, our proposed method rapidly changes not only the spatial patterns but also the polarization states of illumination by using a self-build polarization projector, and captures their effects on a scene by using a high-speed camera. Our method is easy-to-implement, because it does not require projector-camera temporal synchronization and it automatically calibrates the correspondence between the projection pattern and camera pixel. In addition, our method is robust due to the optimized and quickly-shifted projection pattern and the weights for incorporating spatial correlation. We implemented the prototype setup and achieved fast separation with 60 fps.

DOI： 10.1007/978-3-030-81638-4_24

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）

Describing the color and textural information of a person image is one of the most crucial aspects of person re-identification (re-id). Although a covariance descriptor has been successfully applied to person re-id, it loses the local structure of a region and mean information of pixel features, both of which tend to be the major discriminative information for person re-id. In this paper, we present novel meta-descriptors based on a hierarchical Gaussian distribution of pixel features, in which both mean and covariance information are included in patch and region level descriptions. More specifically, the region is modeled as a set of multiple Gaussian distributions, each of which represents the appearance of a local patch. The characteristics of the set of Gaussian distributions are again described by another Gaussian distribution. Because the space of Gaussian distribution is not a linear space, we embed the parameters of the distribution into a point of Symmetric Positive Definite (SPD) matrix manifold in both steps. We show, for the first time, that normalizing the scale of the SPD matrix enhances the hierarchical feature representation on this manifold. Additionally, we develop feature norm normalization methods with the ability to alleviate the biased trends that exist on the SPD matrix descriptors. The experimental results conducted on five public datasets indicate the effectiveness of the proposed descriptors and the two types of normalizations.

DOI： 10.1109/TPAMI.2019.2914686

Scopus

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

Copyright © 2020 by SCITEPRESS - Science and Technology Publications, Lda. All rights reserved. Fluorescent materials give us a unique sense of quality such as self-luminous ones, because they absorb light with certain wavelengths and then emit light with longer wavelengths. The existing methods for image-based material editing make objects in an image specular, translucent, and transparent, but they do not address fluorescent materials. In this paper, we propose a method for making reflective objects in a single input image fluorescent by adding photorealistic fluorescent components to the objects of interest. Specifically, we show that photometrically consistent fluorescent components can approximately be represented by using the 3-band (RGB) spectral irradiance on the surface of a reflective object, and then compute the fluorescent components on the basis of intrinsic image decomposition without explicitly estimating the object's shape and the light sources illuminating it from the input image. We conducted a number of experiments using both synthetic and real images, and confirmed that our proposed method is effective for making reflective objects fluorescent.

Scopus

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

Copyright © 2020 by SCITEPRESS – Science and Technology Publications, Lda. All rights reserved Artificial light sources powered by an electric grid change their intensities in response to the grid’s alternating current (AC). Their flickers are usually too fast to notice with our naked eyes, but can be captured by using cameras with short exposure time settings. In this paper, we propose a method for light source separation under AC illumination on the basis of Blind Source Separation (BSS). Specifically, we show that light source separation results in matrix factorization, since the input images of a scene illuminated by multiple AC light sources are represented by the linear combinations of the basis images, each of which is the image of the scene illuminated by only one of the light sources, with the coefficients, each of which is the intensity of the light source. Then, we make use of Non-negative Matrix Factorization (NMF), because both the pixel values of the basis images and the intensities of the light sources are non-negative. We experimentally confirmed that our method using NMF works better than Independent Component Analysis (ICA), and studied the performance of our method under various conditions: varying exposure times and noise levels.

Scopus

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担当区分：筆頭著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（商業誌、新聞、ウェブメディア）

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

© 2019 IEEE. In this paper, we address the separation of reflective and fluorescent components in RGB images taken under narrow-band light sources such as LEDs. First, we show that the fluorescent color per pixel can be estimated from at least two images under different light source colors, because the observed color at a surface point is represented by a convex combination of the light source color and the illumination-invariant fluorescent color. Second, we propose a method for robustly estimating the fluorescent color via MAP estimation by taking the prior knowledge with respect to fluorescent colors into consideration. We conducted a number of experiments by using both synthetic and real images, and confirmed that our proposed method works better than the closely related state-of-the-art method and enables us to separate reflective and fluorescent components even from a single image. Furthermore, we demonstrate that our method is effective for applications such as image-based material editing and relighting.

DOI： 10.1109/CVPR.2019.00776

Scopus

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

© 2019 IEEE In this paper, we propose a method for separating direct and global components of a dynamic scene per illumination color by using a projector-camera system; it exploits both the color switch and the temporal dithering of a DLP projector. Our proposed method is easy-to-implement because it does not require any self-built equipment and temporal synchronization between a projector and a camera. In addition, our method automatically calibrates the projector-camera correspondence in a dynamic scene on the basis of the consistency in pixel intensities, and optimizes the projection pattern on the basis of noise propagation analysis. We implemented the prototype setup and achieved multispectral direct-global separation of dynamic scenes in 60 Hz. Furthermore, we demonstrated that our method is effective for applications such as image-based material editing and multispectral relighting of dynamic scenes where wavelength-dependent phenomena such as fluorescence are observed.

DOI： 10.1109/WACV.2019.00209

Scopus

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

© Springer Nature Switzerland AG 2018. The quick detection of specific substances in objects such as produce items via non-destructive visual cues is vital to ensuring the quality and safety of consumer products. At the same time, it is well-known that the fluorescence excitation-emission characteristics of many organic objects can serve as a kind of “fingerprint” for detecting the presence of specific substances in classification tasks such as determining if something is safe to consume. However, conventional capture of the fluorescence excitation-emission matrix can take on the order of minutes and can only be done for point measurements. In this paper, we propose a coded illumination approach whereby light spectra are learned such that key visual fluorescent features can be easily seen for material classification. We show that under a single coded illuminant, we can capture one RGB image and perform pixel-level classifications of materials at high accuracy. This is demonstrated through effective classification of different types of honey and alcohol using real images.

DOI： 10.1007/978-3-030-01237-3_31

Scopus

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

© 2017 IEEE. In this paper, we propose a method for image-based relighting with 5-D incident light fields: 4 DoF of the position and direction and 1 DoF of the color of an incident ray. Specifically, we illuminate a scene with various rays by using a two-layer 5 DoF lighting system consisting of a rear-projection display and a transmissive LC panel, and synthesize images under desired 5-D incident light fields by combining the images captured under those rays. Our proposed method efficiently acquires the required images by using coded illumination; it reduces the number of captured images and the measurement time, and enhances their SNRs. In addition, we propose a method for removing the effects of the black offsets due to the projector and the LC panel in the two-layer setup. The experimental results using the prototype system show that our method enables us to synthesize photo-realistic images of scenes where wavelength-dependent phenomena such as fluorescence are observed.

DOI： 10.1109/ICCVW.2017.358

Scopus

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

© 2017. The copyright of this document resides with its authors. Classifying materials and their surface states is important for machine vision applications such as visual inspection. In this paper, we propose an approach to one-shot per-pixel classification of raw materials on the basis of spectral BRDFs; a surface of interest is illuminated by multispectral and multidirectional light sources at the same time. Specifically, we achieve two-class classification from a single color image; it directly finds the linear discriminant hyperplane with the maximal margin in the spectral BRDF feature space by jointly optimizing the non-negative coded illumination and the grayscale conversion. In addition, we extend our method to multiclass classification by exploiting the degree of freedom of the grayscale conversion. The experiments using an LED-based multispectral dome show that the performance of our proposed method with only a single image is better than or comparable to the state-of-the-art methods with multiple images.

Scopus

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

© 2017 IEEE. Separating diffuse and specular reflection components is important for preprocessing of various computer vision techniques such as photometric stereo. In this paper, we address diffuse-specular separation for photometric stereo based on light fields. Specifically, we reveal the low-rank structure of the multi-view images under varying light source directions, and then formulate the diffuse-specular separation as a low-rank approximation of the 3rd order tensor. Through a number of experiments using real images, we show that our proposed method, which integrates the complement clues based on varying light source directions and varying viewing directions, works better than existing techniques.

DOI： 10.1109/ICIP.2017.8296759

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）

© Copyright 2016 The Institute of Electronics, Information and Communication Engineers.We propose a framework to perform auto-radiometric calibration in photometric stereo methods to estimate surface orientations of an object from a sequence of images taken using a radiometrically uncalibrated camera under varying illumination conditions. Our proposed framework allows the simultaneous estimation of surface normals and radiometric responses, and as a result can avoid cumbersome and time-consuming radiometric calibration. The key idea of our framework is to use the consistency between the irradiance values converted from pixel values by using the inverse response function and those computed from the surface normals. Consequently, a linear optimization problem is formulated to estimate the surface normals and the response function simultaneously. Finally, experiments on both synthetic and real images demonstrate that our framework enables photometric stereo methods to accurately estimate surface normals even when the images are captured using cameras with unknown and nonlinear response functions.

DOI： 10.1587/transinf.2016EDP7150

Scopus

CiNii Article

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

© 2016 IEEE.The appearance of an object depends on the color as well as the direction of a light source illuminating the object. The progress of LEDs enables us to capture the images of an object under multispectral and multidirectional light sources. Separating diffuse and specular reflection components in those images is important for preprocessing of various computer vision techniques such as photometric stereo, material editing, and relighting. In this paper, we propose a robust method for separating reflection components in a set of images of an object taken under multispectral and multidirectional light sources. We consider the set of images as the 3D data whose axes are the pixel, the light source color, and the light source direction, and then show the inherent structures of the 3D data: the rank 2 structure derived from the dichromatic reflection model, the rank 3 structure derived from the Lambert model, and the sparseness of specular reflection components. Based on those structures, our proposed method separates diffuse and specular reflection components by combining sparse NMF and SVD with missing data. We conducted a number of experiments by using both synthetic and real images, and show that our method works better than some of the state-of-the-art techniques.

DOI： 10.1109/ICPR.2016.7900129

Scopus

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

© 2016 IEEE.Acquiring the light transport (LT) of a scene is important for various applications such as radiometric analysis, image-based relighting, and controlling appearance of the scene. The multispectral LT, i.e. the LT in multiple primary colors enables us not only to enhance the color gamut but also to investigate wavelength-dependent interactions between light and a scene. In this paper, we propose a method for acquiring the multispectral LT by using a single off-the-shelf multi-primary DLP (Digital Light Processing) projector; it does not require any self-built equipment, geometric registration, and temporal synchronization. Specifically, based on the rapid color switch due to a rotating color wheel in the projector, we present a method for estimating the spectral properties of the projector in a non-destructive manner, and a method for acquiring the images of a scene illuminated only by one of the primary colors. We conducted a number of experiments by using real images, and confirmed that our method works well and the acquired multispectral LT is effective for radiometric analysis and image-based relighting.

DOI： 10.1109/IPTA.2016.7820966

Scopus

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

Copyright © 2016 The Institute of Electronics, Information and Communication Engineers.Self-luminous light sources in the real world often have nonnegligible sizes and radiate light inhomogeneously. Acquiring the model of such a light source is highly important for accurate image synthesis and understanding. In this paper, we propose an approach to measuring 4D light fields of self-luminous extended light sources by using a liquid crystal (LC) panel, i.e. a programmable optical filter and a diffuse-reflection board. The proposed approach recovers the 4D light field from the images of the board illuminated by the light radiated from a light source and passing through the LC panel. We make use of the feature that the transmittance of the LC panel can be controlled both spatially and temporally. The approach enables multiplexed sensing and adaptive sensing, and therefore is able to acquire 4D light fields more efficiently and densely than the straightforward method. We implemented the prototype setup, and confirmed through a number of experiments that our approach is effective for modeling self-luminous extended light sources in the real world.

DOI： 10.1587/transinf.2016EDP7068

Scopus

CiNii Article

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記述言語：英語   掲載種別：研究論文（学術雑誌）

© 2015 IEEE.In recent years, fluorescence analysis of scenes has received attention in computer vision. Fluorescence can provide additional information about scenes, and has been used in applications such as camera spectral sensitivity estimation, 3D reconstruction, and color relighting. In particular, hyperspectral images of reflective-fluorescent scenes provide a rich amount of data. However, due to the complex nature of fluorescence, hyperspectral imaging methods rely on specialized equipment such as hyperspectral cameras and specialized illuminants. In this paper, we propose a more practical approach to hyperspectral imaging of reflective-fluorescent scenes using only a conventional RGB camera and varied colored illuminants. The key idea of our approach is to exploit a unique property of fluorescence: the chromaticity of fluorescent emissions are invariant under different illuminants. This allows us to robustly estimate spectral reflectance and fluorescent emission chromaticity. We then show that given the spectral reflectance and fluorescent chromaticity, the fluorescence absorption and emission spectra can also be estimated. We demonstrate in results that all scene spectra can be accurately estimated from RGB images. Finally, we show that our method can be used to accurately relight scenes under novel lighting.

DOI： 10.1109/TPAMI.2015.2439270

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）

© 1979-2012 IEEE.Hyperspectral imaging is beneficial to many applications but most traditional methods do not consider fluorescent effects which are present in everyday items ranging from paper to even our food. Furthermore, everyday fluorescent items exhibit a mix of reflection and fluorescence so proper separation of these components is necessary for analyzing them. In recent years, effective imaging methods have been proposed but most require capturing the scene under multiple illuminants. In this paper, we demonstrate efficient separation and recovery of reflectance and fluorescence emission spectra through the use of two high frequency illuminations in the spectral domain. With the obtained fluorescence emission spectra from our high frequency illuminants, we then describe how to estimate the fluorescence absorption spectrum of a material given its emission spectrum. In addition, we provide an in depth analysis of our method and also show that filters can be used in conjunction with standard light sources to generate the required high frequency illuminants. We also test our method under ambient light and demonstrate an application of our method to synthetic relighting of real scenes.

DOI： 10.1109/TPAMI.2015.2473839

Scopus

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

Describing the color and textural information of a person image is one of the most crucial aspects of person reidentification. In this paper, we present a novel descriptor based on a hierarchical distribution of pixel features. A hierarchical covariance descriptor has been successfully applied for image classification. However, the mean information of pixel features, which is absent in covariance, tends to be major discriminative information of person images. To solve this problem, we describe a local region in an image via hierarchical Gaussian distribution in which both means and covariances are included in their parameters. More specifically, we model the region as a set of multiple Gaussian distributions in which each Gaussian represents the appearance of a local patch. The characteristics of the set of Gaussians are again described by another Gaussian distribution. In both steps, unlike the hierarchical covariance descriptor, the proposed descriptor can model both the mean and the covariance information of pixel features properly. The results of experiments conducted on five databases indicate that the proposed descriptor exhibits remarkably high performance which outperforms the state-ofthe-art descriptors for person re-identification.

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1109/TIP.2015.2445295

Scopus

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1109/TPAMI.2015.2389841

Scopus

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

Copyright © 2015 SCITEPRESS - Science and Technology Publications All rights reserved.Inverse lighting is a technique for recovering the lighting environment of a scene from a single image of an object. Conventionally, inverse lighting assumes that a pixel value is proportional to radiance value, i.e. the response function of a camera is linear. Unfortunately, however, consumer cameras usually have unknown and nonlinear response functions, and therefore conventional inverse lighting does not work well for images taken by those cameras. In this study, we propose a method for simultaneously recovering the lighting environment of a scene and the response function of a camera from a single image. Through a number of experiments using synthetic images, we demonstrate that the performance of our proposed method depends on the lighting distribution, response function, and surface albedo, and address under what conditions the simultaneous recovery of the lighting environment and response function works well.

Scopus

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

Copyright © 2015 SCITEPRESS - Science and Technology Publications All rights reserved.Spectral reflectance is inherent characteristics of an object surface and therefore useful not only for computer vision tasks such as material classification but also compute graphics applications such as relighting. In this study, by integrating multispectral imaging and photometric stereo, we propose a method for simultaneously estimating the spectral reflectance and normal per pixel from a small number of images taken under multispectral and multidirectional light sources. In addition, taking attached shadows observed on curved surfaces into consideration, we derive the minimum number of images required for the simultaneous estimation and propose a method for selecting the optimal set of light sources. Through a number of experiments using real images, we show that our proposed method can estimate spectral reflectances without the ambiguity of per-pixel scales due to unknown normals, and that, when the optimal set of light sources is used, our method performs as well as the straightforward method using a large number of images. Moreover, we demonstrated that estimating both the spectral reflectances and normals is useful for relighting under novel illumination conditions.

Scopus

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

© Springer International Publishing Switzerland 2015.In this paper, we propose a MAP-based multiframe superresolution method for flickering objects such as LED electronic message boards. Since LED message boards often flicker at low refresh rates, missing areas where LEDs are off during the exposure time of a camera by chance are observed. To suppress unexpected artifacts due to those missing areas, our proposed method detects outlier pixels on the basis of the spatio-temporal analysis of pixel values, and removes them from the MAP estimation by incorporating the weights of pixels into the likelihood term. We conducted a number of experiments using both real and synthetic images, and qualitatively and quantitatively confirmed that our method works better than the existing methods.

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1007/s11263-013-0687-z

Scopus

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1007/978-3-319-16181-5_45

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1109/ICPR.2014.681

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1109/CVPR.2014.278

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1016/j.imavis.2014.01.005

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1109/TPAMI.2014.2313123

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1109/ICCV.2013.63

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1016/j.cviu.2013.06.005

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.5244/C.27.41

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.2197/ipsjtcva.5.114

Scopus

CiNii Article

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1109/CVPR.2013.196

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

This paper addresses the problem of estimating human gaze from eye appearance under free head motion. Allowing head motion remains challenging because eye appearance changes significantly for different head poses, and thus new head poses require new training images. To avoid repetitive training, we propose to produce synthetic training images for varying head poses. First, we model pixel displacements between head-moving eye images as 1D pixel flows, and then produce such flows to synthesize new training images from the original training images captured under a fixed default head pose. Specifically, we produce all the required 1D flows by using only four additionally captured images. Our method was successfully tested with extensive experiments to demonstrate its effectiveness. © 2012 ICPR Org Committee.

Scopus

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84874568334&origin=inward

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

We propose a method for extracting and combining small-scale and large-scale illumination insensitive features for face recognition that can work even in the presence of cast shadows. Although several methods have been proposed to extract such features, they are not designed to handle severe lighting variation on a face and thus fail to work if cast shadows are present. In this paper, we extend quotient image-based illumination normalization by explicitly taking cast shadows into account so that illumination insensitive large-scale features can be obtained. The experimental results show that the proposed method achieves favorable normalization results under difficult illuminations with cast shadows. © 2012 ICPR Org Committee.

Scopus

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84874563451&origin=inward

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1007/978-3-642-37447-0_5

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1109/CVPR.2012.6247752

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1109/CVPR.2012.6247685

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1145/2168556.2168629

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1007/978-3-642-25367-6_25

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1109/ICCVW.2011.6130456

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1109/ICCVW.2011.6130328

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1109/ICCV.2011.6126237

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

The validity of using conventional saliency map models to predict human attention was investigated for video captured with an egocentric camera. Since conventional visual saliency models do not take into account visual motion caused by camera motion, high visual saliency may be erroneously assigned to regions that are not actually visually salient. To evaluate the validity of using saliency map models for egocentric vision, an experiment was carried out to examine the correlation between visual saliency maps and measured gaze points for egocentric vision. The results show that conventional saliency map models can predict visually salient regions better than chance for egocentric vision and that the accuracy decreases significantly with an increase in visual motion induced by egomotion, which is presumably compensated for in the human visual system. This latter finding indicates that a visual saliency model is needed that can better predict human visual attention from egocentric videos. © 2011 Springer-Verlag Berlin Heidelberg.

DOI： 10.1007/978-3-642-22822-3_42

Scopus

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=80053129644&origin=inward

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.5244/C.25.126

Scopus

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1109/CVPR.2011.5995539

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1109/CVPR.2011.5995406

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1109/3DIMPVT.2011.13

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

We present a novel technique for enhancing an image captured in low light by using near-infrared flash images. The main idea is to combine a color image with near-infrared flash images captured at the same time without causing any interference with the color image. In this work, near-infrared flash images are effectively used for removing annoying effects that are commonly observed in images of dimly lit environments, namely, image noise and motion blur. Our denoising method uses a pair of color and near-infrared flash images captured simultaneously. Therefore it is applicable to dynamic scenes, whereas existing methods assume stationary scenes and require a pair of flash and no-flash color images captured sequentially. Our deblurring method utilizes a set of near-infrared flash images captured during the exposure time of a single color image and directly acquires a motion blur kernel based on optical flow. We implemented a multispectral imaging system and confirmed the effectiveness of our technique through experiments using real images. © Springer-Verlag 2010.

DOI： 10.1007/978-3-642-12307-8_20

Scopus

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=78650466182&origin=inward

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.2197/ipsjtcva.2.215

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1109/TIFS.2010.2074194

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1007/978-3-642-19315-6_8

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

DOI： 10.1007/978-3-642-19315-6_25

Scopus

担当区分：責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

Most previous methods for generic object recognition explicitly or implicitly assume that an image contains objects from a single category, although objects from multiple categories often appear together in an image. In this paper, we present a novel method for object recognition that explicitly deals with objects of multiple categories coexisting in an image. Furthermore, our proposed method aims to recognize objects by taking advantage of a scene's context represented by the co-occurrence relationship between object categories. Specifically, our method estimates the mixture ratios of multiple categories in an image via MAP regression, where the likelihood is computed based on the linear combination model of frequency distributions of local features, and the prior probability is computed from the co-occurrence relation. We conducted a number of experiments using the PASCAL dataset, and obtained the results that lend support to the effectiveness of the proposed method. © 2010 National Institute of Informatics.

Scopus

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受賞国：ニュージーランド

受賞国：日本国