Updated on 2023/09/06

写真a

 
KUBOTA Akira
 
Organization
Faculty of Science and Engineering Associate Professor
Other responsible organization
Electrical, Electronic, and Communication Engineering Course of Graduate School of Science and Engineering, Master's Program
Contact information
The inquiry by e-mail is 《here
External link

Degree

  • 工学博士 ( 東京大学 )

  • 工学修士 ( 東京大学 )

Education

  • 2002.3
     

    The University of Tokyo   Graduate School, Division of Engineering   doctor course   completed

  • 1999.3
     

    The University of Tokyo   Graduate School, Division of Engineering   master course   completed

  • 1997.3
     

    Oita University   Faculty of Engineering   graduated

  • 1993.3
     

    大分県立大分上野丘高等学校   graduated

Research History

  • 2011.4 -  

    中央大学理工学部准教授

  • 2009.4 - 2011.3

    中央大学理工学部電気電子情報通信工学科助教

  • 2006.4 - 2009.3

    東京工業大学大学院総合理工学研究科物理情報システム専攻助教

  • 2005.4 - 2006.3

    東京工業大学大学院総合理工学研究科物理情報システム専攻助手

  • 2004.8 - 2005.3

    神奈川大学ハイテク・リサーチ・センターポスト・ドクター研究員

  • 2002.4 - 2004.7

    東京大学大学院新領域創成科学研究科日本学術振興会特別研究員

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Professional Memberships

  • IEEE

  • 電子情報通信学会

Research Interests

  • image information processing

  • 画像情報処理

Research Areas

  • Informatics / Perceptual information processing

Papers

  • Evaluation of Pseudo-Haptics system feedbacking muscle activity Reviewed

    Yoshihito Tanaka, Akira Kubota

    28th ACM Symposium on Virtual Reality Software and Technology   2022.11

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    Publishing type:Research paper (international conference proceedings)   Publisher:ACM  

    DOI: 10.1145/3562939.3565682

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  • Restoring Edge and Color using Weighted Near-Infrared Image and Color Transmission Maps for Robust Haze Removal Reviewed

    Onhi Kato, Akira Kubota

    2022 Asia-Pacific Signal and Information Processing Association Annual Summit and Conference (APSIPA ASC)   2022.11

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    Publishing type:Research paper (international conference proceedings)   Publisher:IEEE  

    DOI: 10.23919/apsipaasc55919.2022.9979960

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  • Scene-Independent Optimum View Interpolation Filters for Stereo Images Reviewed

    Seiji Nakatsubo, Akira Kubota

    The Eleventh International Workshop on Image Media Quality and its Applications (IMQA2022)   OS2-3   2022.3

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  • Robust and Efficient Homography Estimation Using Directional Feature Matching of Court Points for Soccer Field Registration Reviewed

    Kazuki KASAI, Kaoru KAWAKITA, Akira KUBOTA, Hiroki TSURUSAKI, Ryosuke WATANABE, Masaru SUGANO

    IEICE Transactions on Information and Systems   E104.D ( 10 )   1563 - 1571   2021.10

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    Publishing type:Research paper (scientific journal)   Publisher:Institute of Electronics, Information and Communications Engineers (IEICE)  

    DOI: 10.1587/transinf.2021pcp0003

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  • Cauchy Aperture and Perfect Reconstruction Filters for Extending Depth-of-Field from Focal Stack Reviewed

    Akira KUBOTA, Kazuya KODAMA, Asami ITO

    IEICE Transactions on Information and Systems   E102.D ( 11 )   2093 - 2100   2019.11

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    Publishing type:Research paper (scientific journal)   Publisher:Institute of Electronics, Information and Communications Engineers (IEICE)  

    DOI: 10.1587/transinf.2019pcp0006

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  • FAST CAMERA SELF-CALIBRATION FOR SYNTHESIZING FREE VIEWPOINT SOCCER VIDEO Reviewed

    Qiang Yao, Akira Kubota, Kaoru Kawakita, Keisuke Nonaka, Hiroshi Sankoh, Sei Naito

    2017 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING (ICASSP)   1612 - 1616   2017

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    Recently, non-fixed camera-based free viewpoint sports video synthesis has become very popular. Camera calibration is an indispensable step in free viewpoint video synthesis, and the calibration has to be done frame by frame for a non-fixed camera. Thus, calibration speed is of great significance in realtime application. In this paper, a fast self-calibration method for a non-fixed camera is proposed to estimate the homography matrix between a camera image and a soccer field model. As far as we know, it is the first time to propose constructing feature vectors by analyzing crossing points of field lines in both camera image and field model. Therefore, different from previous methods that evaluate all the possible homography matrices and select the best one, our proposed method only evaluates a small number of homography matrices based on the matching result ofthe constructed feature vectors. Experimental results show that the proposed method is much faster than other methods with only a slight loss of calibration accuracy that is negligible in final synthesized videos.

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  • 焦点の異なるステレオ画像からの線形フィルタによる視点内挿法 Reviewed

    久保田 彰, 児玉 和也, 羽鳥 好律

    電子情報通信学会論文誌 D   Vol.J98-D ( 10 )   1325 - 1334   2015.10

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    Authorship:Lead author  

    DOI: 10.14923/transinfj.2015JDP7025

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  • LINEAR VIEW/IMAGE RESTORATION FOR DENSE LIGHT FIELDS Reviewed

    Kazuya Kodama, Akira Kubota

    2014 IEEE INTERNATIONAL CONFERENCE ON IMAGE PROCESSING (ICIP)   5462 - 5466   2014

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    Scene refocusing and free viewpoint image reconstruction from a dense light field acquired by a massive camera array or a lens array are actively studied. However, it is difficult to directly integrate acquired information into a light field without defects. For example, actually, a massive camera array hardly works without failure of several cameras, and part of multi-view images are missing. On the other hand, because a lens array consists of very small lenses gathering only limited rays, acquired images themselves are often noisy. This paper proposes simple linear filters achieving view/image restoration to obtain a dense light field robustly in suppressing such defects without block matching used by the conventional approaches of view synthesis and denoising. Experimental results show that the proposed filters can be flexibly designed for various defects based on the relation between a 4D light field and the corresponding 3D multi-focus images.

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  • Efficient Reconstruction of All-in-Focus Images Through Shifted Pinholes from Multi-Focus Images for Dense Light Field Synthesis and Rendering Reviewed

    Kazuya Kodama, Akira Kubota

    IEEE TRANSACTIONS ON IMAGE PROCESSING   22 ( 11 )   4407 - 4421   2013.11

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC  

    Scene refocusing beyond extended depth of field for users to observe objects effectively is aimed by researchers in computational photography, microscopic imaging, and so on. Ordinary all-in-focus image reconstruction from a sequence of multi-focus images achieves extended depth of field, where reconstructed images would be captured through a pinhole in the center on the lens. In this paper, we propose a novel method for reconstructing all-in-focus images through shifted pinholes on the lens based on 3D frequency analysis of multi-focus images. Such shifted pinhole images are obtained by a linear combination of multi-focus images with scene-independent 2D filters in the frequency domain. The proposed method enables us to efficiently synthesize dense 4D light field on the lens plane for image-based rendering, especially, robust scene refocusing with arbitrary bokeh. Our novel method using simple linear filters achieves not only reconstruction of all-in-focus images even for shifted pinholes more robustly than the conventional methods depending on scene/focus estimation, but also scene refocusing without suffering from limitation of resolution in comparison with recent approaches using special devices such as lens arrays in computational photography.

    DOI: 10.1109/TIP.2013.2273668

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  • 並列処理に適した非因果的符号化手法を用いたフレーム内適応符号化方式 Reviewed

    王翠, 久保田彰, 羽鳥好律

    画像電子学会論文誌   42 ( 3 )   345 - 357   2013.5

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:The Institute of Image Electronics Engineers of Japan  

    In this paper, we propose a novel multi-encoding method for high efficiency intra-frame coding using multiple hybrid coders that combine non-causal interpolative prediction and orthogonal transforms. For hybrid coders, we set 11 different coding modes that employ different orthogonal transforms and the quantization scan orders. For each 8×8 block, computing in parallel the coding errors of all the coding modes, we adaptively select the best mode that gives the minimum error and then send their quantization information with the selected mode number as the overhead information. The simulation results using the standard test images showed that compared to H.264 (with high complexity mode) the proposed method performs better in the higher coding rate and improves PSNR by 6 dB at most.

    DOI: 10.11371/iieej.42.345

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  • Quality-optimized Encoding of JPEG Images using Transform Domain Sparsification Reviewed

    Junichi Ishida, Gene Cheung, Akira Kubota, Antonio Ortega

    IEEE International Workshop on Multimedia Signal Processing   2012.9

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  • 直交変換・非因果的内挿予測ハイブリッド符号化による符号化効率の向上 Reviewed

    森俊介, 久保田彰, 羽鳥好律

    画像電子学会論文誌   40 ( 6 )   985 - 992   2011.11

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:画像電子学会  

    This paper presents a novel hybrid image coding method that combines interpolative prediction and orthogonal transform to achieve higher compression rate. In 8×8 block-wise manner, the presented method first predicts pixel values using the neighboring pixel values including non-causal ones and transforms the obtained error values into coefficients through discrete cosine transform (DCT). The obtained DCT coefficients are quantized by the feedback quantization scheme so that the coding error power is suppressed when decoded. In the quantization, for further higher compression rate, the presented method switches the quantization order into inverse zigzag scan from zigzag scan and controls the quantization step according to the precomputed coefficient that is the gain of the coding error power. Simulation results show that the proposed method gains higher compression rate by 2.0dB than the conventional method using the interpolative quantization only.

    DOI: 10.11371/iieej.40.985

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  • Depth Map Coding using Graph Based Transform and Transform Domain Sparsification Reviewed

    Gene Cheung, Woo-shik Kim, Antonio Ortega, Junichi Ishida, Akira Kubota

    IEEE 13th International Workshop on Multimedia Signal Processing   1 - 6   2011.10

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  • Virtual Bokeh Reconstruction from a Single System of Lenses Reviewed

    Kazuya Kodama, Akira Kubota

    The Journal of The Institute of Image Information and Television Engineers   65 ( 3 )   372 - 381   2011.3

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:Institute of Image Information and Television Engineers  

    We propose a method of virtual bokeh reconstruction by using only multiple differently-focused images acquired with a single system of lenses. First, we analyzed our previously proposed 3-D blurring filter that combines scene information and the acquired multiple differently-focused images to decompose the filter into ray-sets, each of which goes through a certain point on the lens. A new 2-D filter based on dimension reduction was then designed to allow the ray-sets to be reconstructed without the need to estimate the scene. A weighted composition of them provides free shapes of bokeh, i.e., the desired features of lenses and irises. Virtual bokeh reconstruction was simulated by utilizing synthetic multiple differently-focused images with a number of shapes of bokeh. The criteria for appropriate bokeh for image acquisition were also clarified. Finally, we show experimental results of virtual bokeh reconstruction from real images.

    DOI: 10.3169/itej.65.372

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  • ゴーストを抑制可能な空間不変ディジタル・リフォーカス法 Reviewed

    久保田彰, 児玉和也, 羽鳥好律

    画像電子学会論文誌   39 ( 4 )   421 - 432   2010.7

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  • Robust reconstruction of arbitrarily deformed bokeh from ordinary multiple differently focused images Reviewed

    Kazuya Kodama, Ippeita Izawa, Akira Kubota

    Proceedings - International Conference on Image Processing, ICIP   3989 - 3992   2010

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    This paper deals with a method of generating seriously deformed bokeh on reconstructed images from ordinary multiple differently focused images including just simple bokeh such as Gaussian blurs. We previously proposed scene re-focusing with various iris shapes by applying a three-dimensional filter to the multi-focus images. However, actually the proposed method implicitly assumed that the feature of the iris can be expressed mathematically and it has some symmetry like a horizontally open iris. In this paper, at first, the captured multi-focus images are robustly decomposed into components, each of which goes through its own corresponding pin-hole on the lens, by using dimension reduction and a two-dimensional filter. Then, based on the appropriate composition of the components, reconstruction of arbitrarily deformed bokeh introduced by any user-defined iris is achieved. By some experiments, we show that our novel method can generate even seriously deformed bokeh that does not have simple symmetry. © 2010 IEEE.

    DOI: 10.1109/ICIP.2010.5650900

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  • 帰還差分量子化を用いた内挿予測符号化における量子化順序の適応制御方式 Reviewed

    藤田尚宏, 久保田彰, 羽鳥好律

    映像情報メディア学会誌   63 ( 11 )   1652 - 1658   2009.11

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:The Institute of Image Information and Television Engineers  

    An optimal quantization ordering in the feedback quantization scheme for interpolative prediction coding designed to reduce the coding error power is proposed. This method adaptively selects the optimal quantization order to minimize the coding error power from candidate orders for each one dimensional block of 9x1 pixels. These candidate orders can be determined through a numerical analysis of the coding error with respect to all the quantization orders. Simulation results show that the proposed method can effectively reduce the error power and that selecting the optimal order from only four candidate orders can improve the PSNR by about 2 dB, which is just 0.36 dB below the heighest quality image decoded using all 5040 candidate orders. In the case of two-dimensional blocks, although the numerical analysis shows that the coding error power is almost identical among all the possible orders, simulation results demonstrate that selecting the optimal order from four orders in horizontal and vertical directions improves the PSNR by 2.6dB in the case of an 8×8 block.

    DOI: 10.3169/itej.63.1652

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    Other Link: https://jlc.jst.go.jp/DN/JALC/00340281879?from=CiNii

  • Arbitrary Viewpoint Image Synthesis on Multi-Layered Scene Using Reconstruction Filters Reviewed

    Keita Suzuki, Hiroki Sato, Tadaaki Hosaka, Akira Kubota, Ryutaro Oi, Kazuya Kodama, Takayuki Hamamoto

    2009 INTERNATIONAL SYMPOSIUM ON INTELLIGENT SIGNAL PROCESSING AND COMMUNICATION SYSTEMS (ISPACS 2009)   375 - +   2009

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    In arbitrary viewpoint image synthesis, methods to use shape information of subjects have been widely proposed. However, the shape estimation is generally a time-consuming task, and is not suitable for the real time implementation. In this paper, we focus on the reconstruction filtering method in which arbitrary viewpoint image synthesis is performed without the shape estimation on the assumption that subjects exist on predetermined two planes. We propose an extension of this method to a three (and more)-layered scene and derive the filters. Furthermore, the proposed method is implemented on an FPGA, and favorable image synthesis has been achieved in real time.

    DOI: 10.1109/ISPACS.2009.5383824

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  • Arbitrary viewpoint image synthesis for real-time processing system using multiple image sensors Reviewed

    Hiroki Sato, Sho Ogura, Tadaaki Hosaka, Takayuki Hamamoto, Akira Kubota, Ryutaro Oi, Kazuya Kodama

    Proceedings - VRCAI 2009: 8th International Conference on Virtual Reality Continuum and its Applications in Industry   233 - 237   2009

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    We have studied arbitrary viewpoint image synthesis using multiple sensors based on image-based rendering, in which the depth estimation is required for generating precise virtual images. Major problems in this estimation process include the increase of computational efforts and the decrease in performance for occluded regions. To solve these difficulties, we improve our depth estimation process by using the multi-resolution method and by weighting similar pixels to the target pixel in the block matching. Furthermore, we incorporate the proposed method to our prototype hardware system using the CMOS image sensors we have originally developed. Experimental results show that our proposed method and prototype system are efficient and effective compared to the previous work and that arbitrary viewpoint images are synthesized favorably. Copyright © 2009 by the Association for Computing Machinery, Inc.

    DOI: 10.1145/1670252.1670301

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  • 三次元焦点ぼけ構造からの効率的な自由視点画像生成 Reviewed

    欧曦, 児玉和也, 久保田彰, 浜本隆之

    電子情報通信学会論文誌   J91-D ( 12 )   2854 - 2856   2008.12

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:電子情報通信学会  

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  • Efficient free viewpoint image acquisition from multiple differently focused images Reviewed

    Xi Ou, Takayuki Hamamoto, Akira Kubota, Kazuya Kodama

    Proceedings of SPIE - The International Society for Optical Engineering   6822   2008

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    This paper deals with the technique for generating free viewpoint images by using multi-focus imaging sequences. The method may enable us to realize dense 4-D ray-space reconstruction from 3-D multi-focus imaging sequences. Previously, we proposed a method of generating free viewpoint, iris and focus images directly from multi-focus imaging sequences with a 3-D convolution filter that expresses how the scene is defocused in the sequence. However, the cost of the spatial frequency analysis based on 3-D FFT is not inexpensive. In this paper, efficient reconstruction of free viewpoint images by dimension reduction and 2-D FFT is discussed. We show some experimental results by using synthetic and real images. Epipolar plane images are also reconstructed in order to show the disparity between generated free viewpoint images clearly. © 2008 SPIE-IS&amp
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    DOI: 10.1117/12.767604

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  • Image-Based Refocusing By 3D Filtering Reviewed

    Akira Kubota, Kazuya Kodama, Yoshinori Hatori

    Proc. of Pacific Rim Symposium on Image Video and Technology 2007 (PSIVT2007)   385 - 398   2007.12

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  • Multi-View Imaging and 3DTV Reviewed

    Akira Kubota, Aljoscha Smolic, Marcus Magnor, Masayuki Tanimoto, Tsuhan Chen, Cha Zhang

    Signal Processing Magazine   24 ( 6 )   10 - 21   2007.11

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  • Synthesis of Arbitrary View Images for Real-time Multiple Cameras System Reviewed

    Yasuyuki Haruta, Akira Kubota, Ryutaro Oi, Takayuki Hamamoto

    Proc. of International Conference on Computational Intelligence Robotics and Autonomous Systems 2007 (CIRAS2007)   75 - 80   2007.11

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Massey Univ. (New Zieland)  

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  • A Variational Recovery Method for Virtual View Synthesis Reviewed

    Akira Kubota, Takahiro Saito

    Proc. of International Conference on Image Processing 2007 (ICIP2007)   IV   421 - 424   2007.9

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  • 円形多眼画像からの逆フィルタによる中心視点画像の生成手法 Reviewed

    久保田彰, 児玉和也, 羽鳥好律

    電子情報通信学会論文誌   J90-D ( 7 )   1714 - 1715   2007.7

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  • 次元削減に基づく焦点ぼけ画像群からの効率的な全焦点画像生成 Reviewed

    児玉和也, 久保田彰

    電子情報通信学会論文誌   J90-D ( 7 )   1697 - 1699   2007.7

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  • 2層の奥行きシーンの4視点取得画像から中心視点画像を直接生成するための視点内挿フィルタ Reviewed

    久保田彰, 相澤清晴

    電子情報通信学会論文誌   J90-D ( 7 )   1716 - 1717   2007.7

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:電子情報通信学会  

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  • View interpolation by inverse filtering: Generating the center view using multiview images of circular camera array Reviewed

    Akira Kubota, Kazuya Kodama, Yoshinori Hatori

    VISUAL COMMUNICATIONS AND IMAGE PROCESSING 2007, PTS 1 AND 2   6508   2007

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    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:SPIE-INT SOC OPTICAL ENGINEERING  

    This paper deals with a view interpolation problem using multiple images captured with a circular camera array. An inverse filtering method for reconstructing a virtual image at the center of the camera array is proposed. First, we generate a candidate image by adding all correspondence pixel values based on multiple layers assumed in a scene. Second, we model a linear relationship between the desired virtual image and the candidate image, and then derive the inverse filter to reconstruct the virtual image. Since we can derive the inverse filter independent of the scene structure, the proposed method requires no depth estimation. Simulation results using synthetic images show that increasing the number of cameras and layers improves the quality of the virtual image.

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  • Simple and fast all-in-focus image reconstruction based on three-dimensional/two-dimensional transform and filtering Reviewed

    Kazuya Kodama, Hiroshi Mo, Akira Kubota

    ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings   1   I769 - I772   2007

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    This paper deals with all-in-focus image reconstruction by merging multiple differently focused images. We previously proposed a method of generating an all-in-focus image from multi-focus imaging sequences based on a 3-D filtering. In this paper, we first combine the sequence into a 2-D image. Just by applying a 2-D filter to the image, we realize fast reconstruction of all-in-focus images robustly. In order to reduce the cost of image acquisition, the optimal number of multiple differently focused images is also discussed. In addition, we introduce a simple estimation method utilizing the 2-D filter for the parameter of 3-D blurs. We show experimental results of fast all-in-focus image reconstruction by using synthetic and real images. © 2007 IEEE.

    DOI: 10.1109/ICASSP.2007.366021

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  • Synthesis of Arbitrary View Images Using Depth Estimation Based on Iterative Comparison Reviewed

    Yasuyuki Haruta, Akira Kubota, Ryutaro Oi, Takayuki Hamamoto

    Proc. of International Symposium on Intelligent Signal Processing and Communications 2006 (ISPACS2006)   1   566 - 569   2006.12

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  • A Study on Biometric Authentication based on Arm Sweep Action with Acceleration Sensor Reviewed

    Fuminori Okumura, Akira Kubota, Yoshinori Hatori, Kenji Matsuo, Masayuki Hashimoto, Atsushi Koike

    Proc. of International Symposium on Intelligent Signal Processing and Communications 2006 (ISPACS2006)   219 - 222   2006.12

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  • High-Speed All-in-Focus Image Reconstruction by Merging Multiple Differently Focused Images Reviewed

    Kazuya Kodama, Hiroshi Mo, Akira Kubota

    Proc. of Pacific-Rim Conference on Multimedia 2006 (PCM 2006)   909 - 918   2006.11

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:IEEE  

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  • Free Viewpoint, Iris and Focus Image Generation by Using a Three-Dimensional Filtering Based on Frequency Analysis of Blurs Reviewed

    Kazuya Kodama, Hiroshi Mo, Akira Kubota

    Proc. of International Conference on Acoustics, Speech and Signal Processing 2006 (ICASSP 2006)   II   625 - 628   2006.5

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  • Free iris scene re-focusing based on a three-dimensional filtering of multiple differently focused images Reviewed

    Kazuya Kodama, Hiroshi Mo, Akira Kubota

    Proceedings - International Conference on Image Processing, ICIP   2033 - 2036   2006

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    This paper describes a method of scene re-focusing with various iris shapes by integrating a sequence of multiple differently focused images. First, we introduce a formula that combines the sequence and spatial information of a scene with a convolution of a 3-D blur. The blur expresses how the scene is defocused in the sequence. Based on the formula, in the 3-D frequency domain we can design filters merging certain frequency components of the sequence to generate images that would be acquired with various iris shapes. Some experiments of scene re-focusing using synthetic and real images indicate that we can not only arbitrarily suppress blurs of the sequence but also generate images with asymmetrical blurs like motion blurs. ©2006 IEEE.

    DOI: 10.1109/ICIP.2006.312846

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  • Deconvolution method for view interpolation using multiple images of circular camera array Reviewed

    Akira Kubota, Kazuya Kodama, Yoshinori Hatori

    Proceedings - International Conference on Image Processing, ICIP   1049 - 1052   2006

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    This paper deals with a view interpolation problem using multiple images captured with a circular camera array. A novel deconvolution method for reconstructing a virtual image at the center of the camera array is presented and discussed in a framework of image restoration in the frequency domain. The reconstruction filter does not depend on the scene structure
    therefore the presented method requires no depth estimation. The simulation result using synthetic images shows that increasing the number of the cameras improves the quality of the virtual image. ©2006 IEEE.

    DOI: 10.1109/ICIP.2006.312735

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  • Light Field Renderingにおける合焦判定と全焦点画像合成 Reviewed

    高橋桂太, 久保田彰, 苗村健

    電子情報通信学会論文誌   J88-D-II ( 3 )   573 - 584   2005.3

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:電子情報通信学会  

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  • All-in-focus image generation by merging multiple differently focused images in three-dimensional frequency domain Reviewed

    Kazuya Kodama, Hiroshi Mo, Akira Kubota

    Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)   3767   303 - 314   2005

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    This paper describes a method of image generation based on transformation integrating multiple differently focused images. First, we assume that objects are defocused by a geometrical blurring model. And we combine acquired images on certain imaging planes and spatial frequencies of objects by using a convolution of a three-dimensional blur. Then, we reconstruct an all-in-focus image from the acquired images based on spatial frequency analysis using three-dimensional FFT. Some experiments of image generation utilizing synthesized images and real images are shown and extension of the method integrating multiple differently focused images in three-dimensional frequency domain is discussed. © Springer-Verlag Berlin Heidelberg 2005.

    DOI: 10.1007/11581772_27

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  • Direct filtering method for image based rendering Reviewed

    Akira Kubota, Kiyoharu Aizawa, Tsuhan Chen

    Proceedings - International Conference on Image Processing, ICIP   3   1 - 4   2005

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    Image based rendering (IBR) is basically a light ray resampling method for generating a novel image without aliasing artifacts from a given set of sampled light rays. To avoid aliasing artifacts, conventional methods require an estimate of the scene geometry. In this paper, we present a novel IBR method by linear filtering without estimating the scene geometry, for the simplified case when generating a virtual image at the center of 2×2 sparse camera array for a two depth-layers scene. The reconstruction filter used in the proposed method can derived by integrating all the process in our previously proposed method into an one-shot process. © 2005 IEEE.

    DOI: 10.1109/ICIP.2005.1530313

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  • A Focus Measure for Light Field Rendering Reviewed

    Keita Takahashi, Akira Kubota, Takeshi Naemura

    Proc. of International Conference on Image Processing 2004 (ICIP2004)   4   2475 - 2478   2004.10

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  • Virtual View Synthesis through Linear Processing without Geometry Reviewed

    Akira Kubota, Kiyoharu Aizawa, Tsuhan Chen

    Proc. of International Conference on Image Processing 2004 (ICIP2004)   3   3009 - 3012   2004.10

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    DOI: 10.1109/ICIP.2004.1421746

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    Other Link: https://dblp.uni-trier.de/db/conf/icip/icip2004-5.html#KubotaAC04

  • イメージフュージョンによる任意視点画像の鮮鋭化手法 Reviewed

    久保田彰, 相澤清晴

    情報科学技術レターズ   ( 3 )   201 - 204   2004.9

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  • All-Focused Light Field Rendering Reviewed

    Akira Kubota, Keita Takahashi, Kiyoharu Aizawa, Tsuhan Chen

    Proc. of Eurographics Symposium on Rendering 2004 (EGSR2004)   235 - 242   2004.6

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    DOI: 10.2312/EGWR/EGSR04/235-242

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    Other Link: https://dblp.uni-trier.de/db/conf/rt/rt2004.html#KubotaTAC04

  • Reconstructing dense light field from a multi-focus images array Reviewed

    Akira Kubota, Kiyoharu Aizawa, Tsuhan Chen

    Proc. of International Conference on Multimedia and Expo 2004 (ICME2004)   III   2183 - 2186   2004.6

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  • All in-focus image synthesis from under-sampled light fields Reviewed

    Keita Takahashi, Akira Kubota, Takeshi Naemura

    Proc. of International Conference on Artificial Reality and Telexistence 2003 (ICAT2003)   249 - 256   2003.12

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  • A novel image-based rendering method by linear filtering of multiple focused images acquired by a camera array Reviewed

    A Kubota, K Aizawa

    2003 INTERNATIONAL CONFERENCE ON IMAGE PROCESSING, VOL 3, PROCEEDINGS   701 - 704   2003

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    In this paper, we present a novel approach to image-based rendering (IBR) for generating an arbitrary view image with arbitrary focus for a scene consisting two approximately constant depths. The presented method differs from the conventional IBRs using multiple view images in that we acquire two differently focused images from each camera position and render parallax and focus effects on objects at different depth simply by linear filtering of the acquired images without segmentation. Experimental results on the real images acquired with 4 cameras located in parallel are presented.

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  • Object-based approach to image-based rendering with linear filters using defocus information Reviewed

    A Kubota, K Aizawa

    VISUAL COMMUNICATIONS AND IMAGE PROCESSING 2003, PTS 1-3   5150   1329 - 1336   2003

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    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:SPIE-INT SOC OPTICAL ENGINEERING  

    In this paper, we present a novel approach to image-based rendering (IBR) that for generates an arbitrary view image with arbitrary focus for a scene consisting two approximately constant depths. The presented method differs from the conventional IBRs using multiple view images in that we acquire two differently focused images at each camera position and render parallax and focus effects on each object simply by linear filtering of the acquired images without segmentation. Experimental results on the real images acquired with 4 cameras located in parallel are presented.

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  • 多数の昆虫顕微鏡画像からの全焦点画像と3次元画像の生成 Reviewed

    椿泰範, 久保田彰, 相澤清晴

    映像情報メディア学会誌   56 ( 2 )   263 - 270   2002.2

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  • Virtual view generation by linear processing of two differently focused images Reviewed

    A Kubota, K Aizawa

    16TH INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION, VOL I, PROCEEDINGS   504 - 507   2002

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    This paper presents a novel method to render shifting (parallax) and focussing effects on object in a scene for generating a virtual view image with arbitrary focus. Two differently focused images of a same scene-near-focused image and far-focused image-are used as input images under the assumption that a scene has near and far objects. The proposed method can freely handle the shifting and the focussing effect on each object according to the view point and the focus depth of the virtual camera only by linear filtering of the input images without any segmentation or 3D modeling of the objects. Experimental results using real images are shown to test the performance of the method.

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  • All-focused image generation and 3D modeling from microscopic images of insects Reviewed

    Yasunori Tsubaki, Akira Kubota, Kazuya Kodama, Kiyoharu Aizawa

    Kyokai Joho Imeji Zasshi/Journal of the Institute of Image Information and Television Engineers   56 ( 2 )   263 - 270   2002

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    In this paper, we describe a method for generating an all-focused image from a large number of microscopic images of insects. First, we describe our previously proposed select-and-merge method for all-focused image acquisition. We can obtain good results by using this method for two differently focused images. However, this method can't give a good result when a large number of images are used. We thus developed a method that compares each image with those preceding and following it based on the estimation of focused regions. We compare the results of image reconstruction by using the new method with those obtained by using our previously method. We then generate a 3D image bye using the intensity of an all-focused image and the depth of in-focus regions, both obtained by our proposed method.

    DOI: 10.3169/itej.56.263

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  • Arbitrary view and focus image generation: Rendering object-based shifting and focussing effect by linear filtering Reviewed

    A Kubota, K Aizawa

    2002 INTERNATIONAL CONFERENCE ON IMAGE PROCESSING, VOL I, PROCEEDINGS   489 - 492   2002

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    This paper presents a novel method to render shifting (parallax) and focussing effects on object in a scene for generating a virtual view image with arbitrary focus. Two differently focused images of the same scene-near-focused image and far-focused image are used as input under the assumption that a scene has near and far objects. The proposed method can freely handle the shifting and the focussing effect on each object according to the view point and the focus depth of the virtual camera only by linear filtering of the input images without any segmentation or modeling of the objects. Experimental results using real images are shown to test the performance of the method.

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  • All-focused image generation and 3D modelling of microscopic images of insects Reviewed

    Yasunori Tsubaki, Akira Kubota, Kiyoharu Aizawa

    Proc. of International Conference on Image Processing 2001 (ICIP2001)   197 - 200   2001.10

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    DOI: 10.1109/ICIP.2001.958458

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    Other Link: https://dblp.uni-trier.de/db/conf/icip/icip2001-2.html#TsubakiKA01

  • A new approach to depth range detection by producing depth-dependent blurring effect Reviewed

    A Kubota, K Aizawa

    2001 INTERNATIONAL CONFERENCE ON IMAGE PROCESSING, VOL III, PROCEEDINGS   740 - 743   2001

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    This paper presents a new method for detecting depth range of the scene from two differently focused images This method first generates three images with differently emphasized blui using linear filtering of the two acquired images for mole depth-sensitive estimation. In this point this method is different from the conventional approaches The discrete Fourier transform of the ratio between the generated images is then introduced as a criterion of the depth range Finally through the thresholding, process of the (11-tenon according to its correspondence to the depth oil the basis of imaging model, depth range is estimated in five steps in depth Experiments for synthesized and real images are performed to test the proposed method.

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  • Image based rendering by using multiple differently focused images Reviewed

    Kiyoharu Aizawa, Akira Kubota

    Proc. of Pacific-Rim Conference on Multimedia 2000 (PCM2000)   10 - 13   2000.12

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  • 多焦点動画像の高速レジストレーションとリアルタイム処理 Reviewed

    コニーリアニグナディ, 久保田彰, 相澤清晴

    映像情報メディア学会誌   54 ( 11 )   1657 - 1659   2000.11

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:映像情報メディア学会  

    DOI: 10.3169/itej.54.1657

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    Other Link: https://jlc.jst.go.jp/DN/JALC/00071151243?from=CiNii

  • Object-based visual effects by using multi-focus images and its real-time implementation Reviewed

    Kiyoharu Aizawa, Akira Kubota, Gunadi, C.R

    Proc. of International Conference on Multimedia and Expo 2000 (ICME2000)   I   289 - 292   2000.8

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    DOI: 10.1109/ICME.2000.869598

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    Other Link: https://dblp.uni-trier.de/db/conf/icmcs/icme2000.html#AizawaKG00

  • 複数の異なる焦点画像からの多様な映像生成 Reviewed

    児玉和也, 久保田彰, 相澤清晴, 羽鳥光俊

    映像情報メディア学会誌   54 ( 3 )   426 - 430   2000.3

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  • 多焦点画像処理のための位置合わせ手法と撮像系の構築 Reviewed

    久保田彰, 児玉和也, 相澤清晴

    映像情報メディア学会誌   54 ( 2 )   260 - 267   2000.2

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  • Producing object-based special effects by fusing multiple differently focused images Reviewed

    Kiyoharu Aizawa, Kazuya Kodama, Akira Kubota

    IEEE Transactions on Circuits and Systems for Video Technology   10 ( 2 )   323 - 330   2000

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    We propose a novel approach for producing special visual effects by fusing multiple differently focused images. This method differs from conventional image-fusion techniques because it enables us to arbitrarily generate object-based visual effects such as blurring, enhancement, and shifting. Notably, the method does not need any segmentation. Using a linear imaging model, it directly generates the desired image from multiple differently focused images.

    DOI: 10.1109/76.825731

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  • Inverse filters for reconstruction of arbitrarily focused images from two differently focused images Reviewed

    A Kubota, K Aizawa

    2000 INTERNATIONAL CONFERENCE ON IMAGE PROCESSING, VOL I, PROCEEDINGS   101 - 104   2000

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    This paper describes a novel filtering method to reconstruct an arbitrarily focused image from two differently focused images. Based on the assumption that image scene has two layers - foreground and background -, two differently focused images are used as inputs, one of which is focused on the foreground and the other is focused on the background. The linear equation that holds between these images and the desired image, which is derived from their imaging mod els, can be formulated as an image restoration problem. This paper shows that the solution of this problem exists as an inverse filter and the desired image can be reconstructed only by the linear filters. As a result, reconstruction with high accuracy and fast can be achieved. Experiments using real images are shown.

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  • Inverse filters for generation of arbitrarily focused images Reviewed

    A Kubota, K Aizawa

    VISUAL COMMUNICATIONS AND IMAGE PROCESSING 2000, PTS 1-3   4067   1633 - 1641   2000

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    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:SPIE-INT SOC OPTICAL ENGINEERING  

    This paper describes a novel filtering method to reconstruct an arbitrarily focused image from two differently focused images. Based on the assumption that image scene has two layers - foreground and background -, the method uses the linear imaging model of the acquired two differently focused images and the desired image with arbitrary blurring; effect manipulated independently in each Ia;ver. The linear equation that holds between these images, which is derived fi om the imaging model, can be formulated as image restoration problem. This paper shows the solution of this problem, completely exists as an inverse filter, and the desired image can be reconstructed only by the linear filtering. As a result, reconstruction with high accuracy and fast processing call be achieved. Experiments using real images are shown.

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  • Implicit 3D Approach to Image Generation: Object-Based Visual Effects by Linear Processing of Multiple Differently Focused Images.

    Kiyoharu Aizawa, Akira Kubota, Kazuya Kodama

    Multi-Image Analysis   226 - 237   2000

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    Publishing type:Research paper (international conference proceedings)   Publisher:Springer  

    DOI: 10.1007/3-540-45134-X_17

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    Other Link: https://dblp.uni-trier.de/db/conf/tfcv/tfcv2000.html#AizawaKK00

  • Generation of Various Images Using Multiple Differently Focused Images Reviewed

    Kazuya Kodama, Mitsutoshi Hatori, Akira Kubota, Kiyoharu Aizawa

    The Journal of The Institute of Image Information and Television Engineers   54 ( 3 )   426 - 430   2000

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    DOI: 10.3169/itej.54.426

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  • Image-registration method and multi-focus camera for multi-focus image processing Reviewed

    Akira Kubota, Kazuya Kodama, Kiyoharu Aizawa

    Kyokai Joho Imeji Zasshi/Journal of the Institute of Image Information and Television Engineers   54 ( 2 )   260 - 267   2000

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:Inst. of Image Information and Television Engineers  

    We describe an image-registration method and a camera system for multi-focus image processing. We also describe a novel method for high-speed generation of arbitrarily focused images using graphic accelerator. The registration method uses global and local registration. The former corrects for differences in the displacement and scale between acquired images by using a hierarchical block-matching technique
    the latter corrects for local deformation due to lens distortion. The developed camera can capture three differently focused images simultaneously for the same scene, so that we can generate an arbitrarily focused image for dynamic scene. Finally, we show example motion images with an arbitrary focus generated from two differently focused image sequences captured by the proposed camera.

    DOI: 10.3169/itej.54.260

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  • Registration and blur estimation methods for multiple differently focused images Reviewed

    Akira Kubota, Kazuya Kodama, Kiyoharu Aizawa

    Proc. of International Conference on Image Processing 1999 (ICIP1999)   447 - 45   1999.10

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:IEEE  

    DOI: 10.1109/ICIP.1999.822936

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    Other Link: https://dblp.uni-trier.de/db/conf/icip/icip1999-2.html#KubotaKA99

  • Producing Object-based special effects by integrating multiple differently focused images: implicit 3D approach to image content manipulation Reviewed

    Kiyoharu Aizawa, Kazuya Kodama, Akira Kubota

    Proc. of International Conference on Image Processing 1999 (ICIP1999)   515 - 519   1999.10

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    DOI: 10.1109/ICIP.1999.822949

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    Other Link: https://dblp.uni-trier.de/db/conf/icip/icip1999-2.html#AizawaKK99

  • 複数の異なる焦点画像を用いた視差と焦点ぼけを操作する映像生成 Reviewed

    児玉和也, 久保田彰, 相澤清晴, 羽鳥光俊

    映像情報メディア学会誌   52 ( 9 )   1336 - 1342   1998.9

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Books

  • 基本からわかる 信号処理講義ノート

    ( Role: Joint author)

    オーム社  2014.4 

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  • 3DTV System with Depth-Image-Based Rendering: Architectures, Techniques and Challenges

    ( Role: Joint author)

    Springer  2012.8 

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MISC

  • Filter bank for light fields reconstruction from focal stack

    117 ( 228 )   71 - 73   2017.10

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  • Filter bank for light fields reconstruction from focal stack

    41 ( 33 )   71 - 73   2017.10

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  • 解説「多視点画像を使って焦点ぼけ画像を生成するフィルタ手法」

    久保田彰

    画像ラボ   19 ( 12 )   31 - 35   2008.12

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  • 腕の振りに基づく生体認証とテンプレート更新による経時変化の抑制 Reviewed

    松尾賢治, 奥村文教, 橋本真幸, 小池淳, 久保田彰, 羽鳥好律

    電子情報通信学会論文誌   J91-B ( 6 )   695 - 705   2008.6

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  • 奥行き推定を必要としない視点内挿手法とその安定性解析 ―円周配置の多視点画像を用いた中心視点画像の生成― Reviewed

    久保田彰, 児玉和也, 羽鳥好律

    電子情報通信学会論文誌   J90-D ( 4 )   1063 - 1072   2007.4

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  • Free iris and focus image generation by merging multiple differently focused images based on a three-dimensional filtering

    Kazuya Kodama, Akira Kubota

    IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS   E90D ( 1 )   191 - 198   2007.1

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    Language:English   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    This paper describes a method of free iris and focus image generation based on transformation integrating multiple differently focused images. First, we assume that objects are defocused by a geometrical blurring model. And we combine acquired images on certain imaging planes and spatial information of objects by using a convolution of a three-dimensional blur. Then, based on spatial frequency analysis of the blur, we design three-dimensional filters that generate free iris and focus images from the acquired images. The method enables us to generate not only an all-in-focus image corresponding to an ideal pin-hole iris but also various images, which would be acquired with virtual irises whose sizes are different from the original one. In order to generate a certain image by using multiple differently focused images, especially very many images, conventional methods usually analyze focused regions of each acquired image independently and construct a depth map. Then, based on the map, the regions are merged into a desired image with some effects. However, generally, it is so difficult to conduct such depth estimation robustly in all regions that these methods cannot prevent merged results from including visible artifacts, which decrease the quality of generated images awfully. In this paper, we propose a method of generating desired images directly and robustly from very many differently focused images without depth estimation. Simulations of image generation are performed utilizing synthetic images to study how certain parameters of the blur and the filter affect the quality of generated images. We also introduce pre-processing that corrects the size of acquired images and a simple method for estimating the parameter of the three-dimensional blur. Finally, we show experimental results of free iris and focus image generation from real images.

    DOI: 10.1093/ietisy/e90-d.1.191

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  • Reconstructing dense light field from array of multifocus images for novel view synthesis

    Akira Kubota, Kiyoharu Aizawa, Tsuhan Chen

    IEEE TRANSACTIONS ON IMAGE PROCESSING   16 ( 1 )   269 - 279   2007.1

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    This paper presents a novel method for synthesizing a novel view from two sets of differently focused images taken by an aperture camera array for a scene consisting of two approximately constant depths. The proposed method consists of two steps. The first step is a view interpolation to reconstruct an all-in-focus dense light field of the scene. The second step is to synthesize a novel view by a light-field rendering technique from the reconstructed dense light field. The view interpolation in the first step can be achieved simply by linear filters that are designed to shift different object regions separately, without region segmentation. The proposed method can effectively create a dense array of pin-hole cameras (i.e., all-in-focus images), so that the novel view can be synthesized with better quality.

    DOI: 10.1109/TIP.2006.884938

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  • Reconstructing dense light field from array of multifocus images for novel view synthesis

    Akira Kubota, Kiyoharu Aizawa, Tsuhan Chen

    IEEE TRANSACTIONS ON IMAGE PROCESSING   16 ( 1 )   269 - 279   2007.1

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    Language:English   Publisher:IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC  

    This paper presents a novel method for synthesizing a novel view from two sets of differently focused images taken by an aperture camera array for a scene consisting of two approximately constant depths. The proposed method consists of two steps. The first step is a view interpolation to reconstruct an all-in-focus dense light field of the scene. The second step is to synthesize a novel view by a light-field rendering technique from the reconstructed dense light field. The view interpolation in the first step can be achieved simply by linear filters that are designed to shift different object regions separately, without region segmentation. The proposed method can effectively create a dense array of pin-hole cameras (i.e., all-in-focus images), so that the novel view can be synthesized with better quality.

    DOI: 10.1109/TIP.2006.884938

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  • Free iris and focus image generation by merging multiple differently focused images based on a three-dimensional filtering

    Kazuya Kodama, Akira Kubota

    IEICE Transactions on Information and Systems   E90-D ( 1 )   191 - 198   2007

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    Language:English   Publisher:Institute of Electronics, Information and Communication, Engineers, IEICE  

    This paper describes a method of free iris and focus image generation based on transformation integrating multiple differently focused images. First, we assume that objects are defocused by a geometrical blurring model. And we combine acquired images on certain imaging planes and spatial information of objects by using a convolution of a three-dimensional blur. Then, based on spatial frequency analysis of the blur, we design three-dimensional filters that generate free iris and focus images from the acquired images. The method enables us to generate not only an all-in-focus image corresponding to an ideal pin-hole iris but also various images, which would be acquired with virtual irises whose sizes are different from the original one. In order to generate a certain image by using multiple differently focused images, especially very many images, conventional methods usually analyze focused regions of each acquired image independently and construct a depth map. Then, based on the map, the regions are merged into a desired image with some effects. However, generally, it is so difficult to conduct such depth estimation robustly in all regions that these methods cannot prevent merged results from including visible artifacts, which decrease the quality of generated images awfully. In this paper, we propose a method of generating desired images directly and robustly from very many differently focused images without depth estimation. Simulations of image generation are performed utilizing synthetic images to study how certain parameters of the blur and the filter affect the quality of generated images. We also introduce pre-processing that corrects the size of acquired images and a simple method for estimating the parameter of the three-dimensional blur. Finally, we show experimental results of free iris and focus image generation from real images. Copyright © 2007 The Institute of Electornics, Information and Communication Engineers.

    DOI: 10.1093/ietisy/e90-1.1.191

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  • 解説「視点と焦点の異なる画像群を用いたイメージ・ベースド・レンダリング―領域分割をすることなく,焦点ぼけから視差を作り出す視点内挿アルゴリズム―」

    久保田彰, 相澤清晴

    画像ラボ   17 ( 11 )   11 - 14   2006.11

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  • Generation of an all-in-focus image by merging many differently focused images based on a 3-D filtering

    Kazuya Kodama, Akira Kubota

    Kyokai Joho Imeji Zasshi/Journal of the Institute of Image Information and Television Engineers   60 ( 7 )   1077 - 1084   2006.7

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    Language:Japanese  

    A method for generating all-in-focus images by integrating multiple differently focused images is described. First, based on the assumption that objects are defocused by a simple geometrical blurring model, we derive a formula between acquired images on certain imaging planes and spatial information of objects by using a convolution of a 3-D blur. Then, we analyze spatial frequency components of the blur kernel to obtain a 3-D filter that generates an all-in-focus image from the acquired images. Simulations of image generation are performed utilizing synthetic images to study how noise, object depths, and certain parameters of the blur and the filter affect the quality. We also introduce pre-processing that corrects the size of acquired images and a simple method for estimating the parameter of the 3-D blur. Finally, we show experimental results of all-in-focus image generation from real images.

    DOI: 10.3169/itej.60.1077

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  • Special issue on multi-view image processing and its application in image-based rendering

    Akira Kubota, Tsuhan Chen

    SIGNAL PROCESSING-IMAGE COMMUNICATION   21 ( 6 )   451 - 453   2006.7

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    Language:English   Publisher:ELSEVIER SCIENCE BV  

    DOI: 10.1016/j.image.2006.03.010

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  • 解説「画像復元法に基づいた自由視点画像の生成」

    久保田彰, 斉藤隆弘

    OplusE   28 ( 3 )   59 - 62   2006.3

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  • Reconstructing dense light field from a multi-focus images array for virtual view synthesis

    Akira Kubota, Kiyoharu Aizawa

    Kyokai Joho Imeji Zasshi/Journal of the Institute of Image Information and Television Engineers   60 ( 5 )   797 - 806   2006

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    This paper presents a novel method for synthesizing a virtual view from two sets of differently focused images taken by an aperture camera array for a scene of two approximately constant depths. The proposed method consists of two steps. The first step is a view interpolation to reconstruct an all in-focus dense light field of the scene. The second step is to synthesize a virtual view from the reconstructed dense light field by using light field rendering technique. The view interpolation in the first step can be achieved simply with linear filters that are designed to shift different object regions separately without estimating the depth map of the scene. The proposed method can effectively create a dense array of pin-hole cameras (i.e., all-focused images) so that the virtual view can be synthesized with higher quality.

    DOI: 10.3169/itej.60.797

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  • A Study on Structure of Multi-Focus Imaging Sequences for High Quality Image Generation

    KODAMA Kazuya, KUBOTA Akira

    IEICE technical report   105 ( 461 )   19 - 24   2005.12

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    This paper deals with image generation based on transformation integrating multiple differently focused images into structured 3-D information. First, we describes a method of image size correction and focus interpolation for the integration. In addition, relation between a certain parameter of the structured 3-D information and quality of generated images is discussed taking noise into consideration. Furthermore, we examine how errors of assumptions about blurs and scenes degrade generated images. Difference between our proposed method and conventional image restoration such as necessity of using window functions is also mentioned.

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  • A Study on Structure of Multi-Focus Imaging Sequences for High Quality Image Generation

    KODAMA Kazuya, KUBOTA Akira

    IPSJ SIG Notes   2005 ( 124 )   69 - 74   2005.12

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    This paper deals with image generation based on transformation integrating multiple differently focused images into structured 3-D information. First, we describes a method of image size correction and focus interpolation for the integration. In addition, relation between a certain parameter of the structured 3-D information and quality of generated images is discussed taking noise into consideration. Furthermore, we examine how errors of assumptions about blurs and scenes degrade generated images. Difference between our proposed method and conventional image restoration such as necessity of using window functions is also mentioned.

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    Other Link: http://id.nii.ac.jp/1001/00041160/

  • A Study on Structure of Multi-Focus Imaging Sequences for High Quality Image Generation

    KODAMA Kazuya, KUBOTA Akira

    ITE technical report   29 ( 73 )   19 - 24   2005.12

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  • Reconstructing arbitrarily focused images from two differently focused images using linear filters

    A Kubota, K Aizawa

    IEEE TRANSACTIONS ON IMAGE PROCESSING   14 ( 11 )   1848 - 1859   2005.11

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    We present a novel filtering method for reconstructing an all-in-focus image or an arbitrarily focused image from two images that are focused differently. The method can arbitrarily manipulate the degree of blur of the objects using linear filters without segmentation. The filters are uniquely determined from a linear imaging model in the Fourier domain. An effective and accurate blur estimation method is developed. The simulation results show that the accuracy and computational time of the proposed method are improved compared with the previous iterative method and that the effects of blur estimation error on the quality of the reconstructed image are very small. The method performs well for real images acquired without visible artifacts.

    DOI: 10.1109/TIP.2005.854468

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  • Reconstructing arbitrarily focused images from two differently focused images using linear filters

    A Kubota, K Aizawa

    IEEE TRANSACTIONS ON IMAGE PROCESSING   14 ( 11 )   1848 - 1859   2005.11

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    We present a novel filtering method for reconstructing an all-in-focus image or an arbitrarily focused image from two images that are focused differently. The method can arbitrarily manipulate the degree of blur of the objects using linear filters without segmentation. The filters are uniquely determined from a linear imaging model in the Fourier domain. An effective and accurate blur estimation method is developed. The simulation results show that the accuracy and computational time of the proposed method are improved compared with the previous iterative method and that the effects of blur estimation error on the quality of the reconstructed image are very small. The method performs well for real images acquired without visible artifacts.

    DOI: 10.1109/TIP.2005.854468

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  • 解説「顕微鏡画像の全焦点化と奥行き情報の取得 多数枚の昆虫顕微鏡画像からの全焦点画像と3次元画像の生成」

    椿泰範, 久保田彰, 相澤清晴

    画像ラボ   13 ( 10 )   19 - 21   2002.10

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  • 線形フィルタによる2枚の合焦画像からの任意ぼけ画像の再構成 Reviewed

    久保田彰, 相澤清晴

    電子情報通信学会論文誌   J83-D-II ( 12 )   2663 - 2674   2000.12

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Presentations

  • 複数尤度に基づく検出処理を組み合わせたParticle Filterによる人物追跡

    鵜殿康太郎, 久保田 彰

    画像工学研究会  2015.3 

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  • ORB特徴量を用いたParticle Filterによる人物追跡手法

    伊藤剛大, 久保田 彰

    画像工学研究会  2015.2 

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  • 多重解像度分解を用いたシーンのレイヤ表現に基づく視点内挿法

    安田 奨, 久保田 彰

    画像工学研究会  2015.2 

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  • AECを用いた奥行きマップに対する動画圧縮方式

    伊藤一樹, チョン ジーン, 久保田 彰

    画像工学研究会  2015.2 

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  • PNG画像におけるフィルタの最適選択と圧縮特性の改善

    高橋哲平, 久保田 彰

    画像工学研究会  2015.2 

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  • 雑音と欠損視点に対応する光線空間復元

    児玉 和也, 久保田 彰

    映像メディア処理シンポジウム  2014.11 

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  • 近赤外画像を利用した霞のある屋外画像の明瞭化の一手法

    山口浩平, 久保田 彰

    画像工学研究会  2014.11 

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  • 直交変換を用いたNear-Lossless符号化の一検討

    伊藤 一樹, チョン ジーン, 久保田 彰, オルテガ アントニオ

    画像符号化シンポジウム  2013.11 

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  • フィルタの最適選択と色空間変換を用いた PNGの圧縮特性改善

    高橋 哲平, 久保田 彰

    画像符号化シンポジウム  2013.11 

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  • コンピュータトモグラフィを利用した自由視点画像の生成

    久保田彰

    映像メディア処理シンポジウム  2013.11 

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  • 周波数領域上での線型結合に基づくScene Refocusing

    児玉 和也, 久保田 彰

    映像メディア処理シンポジウ  2012.12 

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  • 非因果的フレーム内符号化の簡易な適応選択方式

    王 翠, 久保田 彰, 羽鳥 好律

    画像符号化シンポジウム  2012.10 

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  • 非因果的符号化方式の時間相関方向への拡張

    王 翠, 久保田 彰, 羽鳥 好律

    画像符号化シンポジウム  2011.11 

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  • 反復埋込法を用いた自由視点画像への電子透かし法

    阿部 拓也, 久保田 彰

    映像メディア処理シンポジウム  2011.11 

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  • 複数の周波数帯での奥行推定に基づく自由視点画像合成手法の提案

    中嶋 俊介, 久保田 彰

    映像メディア処理シンポジウム  2011.11 

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  • 固有空間法を用いた顔動画像からの個人認証

    早田 光太郎, 久保田 彰

    映像メディア処理シンポジウム  2011.10 

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  • ペナルティ関数法を用いた奥行マップの疎表現

    石田 淳一, チョン ジーン, 久保田 彰, オルテガ アントニオ

    画像符号化シンポジウム  2011.10 

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  • Free viewpoint image generation using defocus multiview images

    Akira Kubota, Yoshinori Hatori

    信学技報(画像工学研究会),電子情報通信学会  2009.4 

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  • 実写画像に基づいた自由焦点・視点画像の生成

    映像情報メディア学会,次世代画像入力専門研究部会,2008年度研究会  2009.3 

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  • 奥行き変化のあるシーンに対する超解像反復アルゴリズム

    横山あみ, 久保田彰, 羽鳥好律, 酒澤茂之

    画像電子学会 第243回研究会講演予稿,画像電子学会  2009.3 

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  • パラメトリック固有空間法を用いた手持ちカメラからの動画像による本人認証

    森住 祐介, 松尾 賢治, 久保田 彰, 羽鳥 好律

    画像電子学会 第243回研究会講演予稿,画像電子学会  2009.3 

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  • 焦点の異なるステレオ画像からの中間視点画像の生成

    濱中智仁, 久保田彰, 羽鳥好律

    信学技報(画像工学研究会),電子情報通信学会  2008.12 

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  • 奥行き変化のあるシーンに対する高精細画像の反復再構成

    横山あみ, 久保田彰, 羽鳥好律

    信学技報(画像工学研究会),電子情報通信学会  2008.10 

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  • 非因果的内挿によるBピクチャ符号化方式の検討

    原部智哉, 羽鳥好律, 久保田彰

    信学技報(画像工学研究会),電子情報通信学会  2008.10 

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  • パラメトリック固有空間法を用いた手持ちカメラからの動画像による本人認証

    森住祐介, 松尾賢治, 久保田彰, 羽鳥好律

    信学技報(画像工学研究会),電子情報通信学会  2008.10 

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  • 内挿予測・DCT量子化を用いたハイブリッド符号化方式の検討

    森俊介, 久保田彰, 羽鳥好律

    画像符号化シンポジウム資料,電子情報通信学会  2008.10 

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  • 非因果的内挿予測によるBピクチャ符号化方式の検討

    原部智哉, 羽鳥好律, 久保田彰

    画像符号化シンポジウム資料,電子情報通信学会  2008.10 

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  • 多視点画像に基づいた仮想視点画像の超解像処理

    横山あみ, 久保田彰, 羽鳥好律

    映像メディア処理シンポジウム資料,電子情報通信学会  2008.10 

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  • パラメトリック固有空間法を用いた手持ちカメラからの動画像による本人認証の一検討

    森住祐介, 松尾賢治, 小池淳, 久保田彰, 羽鳥好律

    映像メディア処理シンポジウム資料,電子情報通信学会  2008.10 

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  • 画像をたくさん撮ったあとに焦点や視点を変える画像処理~イメージ・ベースド・レンダリング~

    (株)東芝 デジタルメディアネットワーク社 講演会  2008.9 

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  • 手持ちカメラで取得した顔動画像からの個人認証の一検討

    森住祐介, 松尾賢治, 久保田彰, 羽鳥好律

    情報科学技術フォーラム講演論文集,電子情報通信学会  2008.9 

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  • 内挿符号化によるBピクチャ符号化方式の検討

    原部智哉, 羽鳥好律, 久保田彰

    情報科学技術フォーラム講演論文集,電子情報通信学会  2008.9 

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  • 円周配置多眼画像からの視線一致画像の合成と高精細化

    横山あみ, 久保田彰, 羽鳥好律

    情報科学技術フォーラム講演論文集,電子情報通信学会  2008.9 

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  • 反復復元法に基づいた仮想視点画像の生成

    久保田彰, 齊藤隆弘

    信学技報(パターン認識・メディア理解研究会),電子情報通信学会  2008.3 

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  • 画像処理による視点内挿の試み ―視点移動のための線形変換処理―

    計測自動制御学会四国支部講演会  2007.11 

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  • 3次元焦点ぼけ構造からの次元削減に基づく自由視点画像生成

    欧曦, 児玉和也, 久保田彰, 浜本隆之

    映像メディア処理シンポジウム資料,電子情報通信学会  2007.10 

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  • スペクトル分解に基づいたシーン非依存型の視点内挿フィルタ

    久保田彰, 児玉和也, 羽鳥好律

    映像メディア処理シンポジウム資料,電子情報通信学会  2007.10 

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  • 合焦判定法を利用した仮想視点画像の生成

    大澤克俊, 久保田彰, 羽鳥好律

    映像メディア処理シンポジウム資料,電子情報通信学会  2007.10 

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  • 仮想平面を用いた多視点映像の予測内挿符号化方式の検討

    鈴木裕高, 久保田彰, 羽鳥好律

    映像符号化シンポジウム資料,電子情報通信学会  2007.10 

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  • 多視点画像に基づいた焦点効果のレンダリング手法

    久保田彰, 児玉和也, 羽鳥好律

    第6回情報科学技術フォーラム講演集,電子情報通信学会  2007.9 

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  • 合焦判定法を利用した中心視点画像の生成

    大澤克俊, 久保田彰, 羽鳥好律

    第6回情報科学技術フォーラム講演集,電子情報通信学会  2007.9 

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  • 仮想平面を用いた多視点映像の予測内挿符号化方式の検討

    鈴木裕高, 久保田彰, 羽鳥好律

    第6回情報科学技術フォーラム講演集,電子情報通信学会  2007.9 

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  • 合焦判定を用いた仮想視点画像の生成

    大澤克俊, 久保田彰, 羽鳥好律

    信学技報(画像工学研究会),電子情報通信学会  2007.7 

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  • 疎な光線データからのエイリアジングを抑制した焦点ぼけ画像の生成

    久保田彰, 児玉和也, 羽鳥好律

    信学技報(画像工学研究会),電子情報通信学会  2007.7 

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  • 誤り領域判定に基づく多眼カメラを用いた距離推定の高精度化

    小倉翔, 春田康行, 久保田 彰, 大井隆太朗, 浜本隆之

    映情学技報(情報センシング研究会),映像情報メディア学会  2007.6 

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  • 円周配置カメラの実写画像を用いた中心視点画像の生成

    久保田彰, 佐久間あい, 児玉和也, 羽鳥好律

    画像電子学会第231回研究会予稿集,画像電子学会  2007.3 

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  • View interpolation by inverse filtering: generating the center view using multiview images of circular camera array

    Visual Communications and Image Processing 2007  2007 

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  • 仮想平面を用いた多視点映像の予測符号化方式の検討

    2007 

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  • 合焦判定を利用した中心視点画像の生成

    2007 

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  • Generating center-view image by using depth-from-focus

    IEVC2007  2007 

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  • Interpolative prediction based on virtualplane multi-view image coding

    IEVC2007  2007 

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  • View interpolation by inverse filtering: generating the center view using multiview images of circular camera array

    Visual Communications and Image Processing 2007  2007 

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  • Generating center-view image by using depth-from-focus

    IEVC2007  2007 

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  • Interpolative prediction based on virtualplane multi-view image coding

    IEVC2007  2007 

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  • 加速度センサを用いた手振りによる個人認証の研究

    奥村文教, 久保田彰, 羽鳥好律, 松尾賢治, 橋本真幸, 小池淳

    映像メディア処理シンポジウム資料,電子情報通信学会  2006.11 

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  • 次元削減に基づく焦点ぼけ画像群からの効率的な映像生成

    児玉和也, 久保田彰

    映像メディア処理シンポジウム資料,電子情報通信学会  2006.11 

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  • 円周多眼画像からの光線内挿手法

    久保田彰, 児玉和也, 羽鳥好律

    映像メディア処理シンポジウム資料,電子情報通信学会  2006.11 

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  • 円周多眼画像からのウィナーフィルタによる任意焦点画像の再構成

    久保田彰, 児玉和也, 羽鳥好律

    画像の認識・理解シンポジウム講演予稿集,電子情報通信学会  2006.7 

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  • 3次元フィルタリングに基づく焦点ぼけ画像群からの全焦点画像センシング法の提案

    児玉和也, 久保田彰

    第12回センシングシンポジウム講演論文集,画像センシング技術研究会  2006.6 

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  • 円周多眼画像からの任意焦点画像の再構成

    久保田彰, 児玉和也, 羽鳥好律

    信学技報(画像工学研究会),電子情報通信学会  2006.5 

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  • 画像復元法を用いた円周多眼画像からの視点内挿とその安定性

    久保田彰, 児玉和也, 羽鳥好律

    信学技報(サイバーワールド研究会),電子情報通信学会  2006.3 

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  • 信号処理手法によるView Interpolationの試み

    神奈川大学電子情報系ハイテク・リサーチ・センター第2回シンポジウム  2006.2 

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  • Deconvolution Method for View Interpolation using Multiple Images of Circular Camera Array

    IEEE international conference on image processing  2006 

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  • Deconvolution Method for View Interpolation using Multiple Images of Circular Camera Array

    IEEE international conference on image processing  2006 

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  • 高品質な映像生成に適した焦点ぼけ画像群の構造化に関する検討

    児玉和也, 久保田彰

    信学技報(画像工学研究会),電子情報通信学会  2005.12 

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  • 3次元デコンボリューション法による中間視点画像の生成

    久保田彰, 児玉和也, 羽鳥好律

    信学技報(画像工学研究会),電子情報通信学会  2005.11 

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  • 円形多眼画像からの中心画像の再構成問題

    久保田彰, 児玉和也, 相澤清晴, 羽鳥好律

    映像メディア処理シンポジウム資料,電子情報通信学会  2005.11 

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  • 3次元焦点ぼけ構造を用いて視点と焦点ぼけを操作する画像生成

    児玉和也, 久保田彰

    映像メディア処理シンポジウム資料,電子情報通信学会  2005.11 

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  • Light Field Rendering の先鋭化

    第4回情報科学技術フォーラムFIT2005,3次元ビデオ処理に関するシンポジウム  2005.9 

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  • Direct filtering method for image based rendering

    IEEE Int. Conf. Image Processing  2005 

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  • Direct filtering method for image based rendering

    IEEE Int. Conf. Image Processing  2005 

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  • Iterative Reconstruction of Virtual View from Multiple Images Captured with an Unstructured Camera Array

    Akira Kubota, Kiyoharu Aizawa

    信学技報(画像工学研究会),電子情報通信学会  2005.1 

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  • 任意視点画像の反復再構成-不規則配置の多眼カメラ画像への適用-

    久保田彰, 相澤清晴

    映像メディア処理シンポジウム資料,電子情報通信学会  2004.11 

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  • All-Focused Light Field Rendering

    Eurographics Symposium on Rendering  2004 

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  • All-Focused Light Field Rendering

    Eurographics Symposium on Rendering  2004 

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  • 焦点ぼけ情報を利用した任意視点・焦点画像の生成

    久保田彰, 相澤清晴

    3次元画像コンファレンス講演論文集,画像電子学会  2003.7 

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  • 多視点・焦点画像の線形フィルタリングによる任意視点・焦点画像の生成

    久保田彰, 相澤清晴

    映情学技報(メディア工学研究会),映像情報メディア学会  2003.2 

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  • 多焦点ステレオ画像の線形処理による視点と焦点の内挿

    久保田彰, 相澤清晴

    映像メディア処理シンポジウム資料,電子情報通信学会  2002.11 

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  • 多焦点画像を用いたIBRによる仮想視点・任意焦点画像の生成

    久保田彰, 相澤清晴

    日本バーチャルリアリティ学会 第7回大会講演予稿集,日本バーチャルリアリティ学会  2002.9 

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  • 複数のぼけ画像を用いた全焦点画像生成

    大野哲之, 久保田彰, 相澤清晴

    画像の認識・理解シンポジウム講演予稿集,電子情報通信学会  2002.7 

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  • 線形処理を用いた視差と焦点ぼけのレンダリングによる仮想カメラ画像の生成

    久保田彰, 相澤清晴

    画像の認識・理解シンポジウム講演予稿集,電子情報通信学会  2002.7 

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  • ぼけ強調処理による奥行きの推定精度の改善

    久保田彰, 相澤清晴

    映像メディア処理シンポジウム資料,電子情報通信学会  2001.11 

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  • 焦点ぼけの強調による奥行き領域の検出法

    久保田彰, 相澤清晴

    信学技報(パターン認識・メディア理解研究会),電子情報通信学会  2000.12 

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  • 焦点ぼけ付与による奥行き領域の検出法の検討

    久保田彰, 相澤清晴

    映像メディア処理シンポジウム資料,電子情報通信学会  2000.11 

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  • 線形処理による多合焦画像を用いた視覚効果生成

    久保田彰, 相澤清晴

    日本バーチャルリアリティ学会 第5回大会講演予稿集,日本バーチャルリアリティ学会  2000.9 

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  • 線形フィルタを用いた多焦点画像からの視覚効果処理-強調,流れ場,シフト処理-

    久保田彰, 相澤清晴

    映像情報メディア学会 年次大会講演予稿集,映像情報メディア学会  2000.8 

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  • 逆フィルタによる多焦点画像からの映像生成 -焦点ぼけ,流れ場,強調・シフト-

    久保田彰, 相澤清晴

    画像の認識・理解シンポジウム講演予稿集,電子情報通信学会  2000.7 

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  • 多焦点画像からの逆フィルタによる任意焦点画像の再構成

    久保田彰, 相澤清晴

    映像メディア処理シンポジウム資料,電子情報通信学会  1999.9 

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  • 顕微鏡を用いた非常に多数枚の昆虫画像からの超高精細全焦点画像再構成の検討

    児玉和也, 久保田彰, 椿泰範, 相澤清晴, 羽鳥光俊

    映像メディア処理シンポジウム資料,電子情報通信学会  1999.9 

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  • 回転とスケール変化を考慮した多焦点画像のレジストレーション手法

    久保田彰, 相澤清晴

    映像情報メディア学会 年次大会講演予稿集,映像情報メディア学会  1999.8 

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  • 多焦点画像の回転を考慮したレジストレーションと任意焦点画像の逆フィルタによる高速再構成

    久保田彰, 相澤清晴

    信学技報(画像工学研究会),電子情報通信学会  1999.7 

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  • 多焦点画像処理のためのグローバル/ローカルレジストレーションと多焦点動画像カメラの試作

    久保田彰, 児玉和也, 相澤清晴, 羽鳥光俊

    信学技報(パターン認識・メディア理解研究会),電子情報通信学会  1999.3 

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  • 任意焦点画像処理用撮像カメラの試作

    久保田彰, 児玉和也, 相澤清晴, 羽鳥光俊

    映像メディア処理シンポジウム資料,電子情報通信学会  1998.10 

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  • 焦点画像処理のための複数焦点画像間のレジストレーションとぼけ推定

    久保田彰, 児玉和也, 相澤清晴, 羽鳥光俊

    電子情報通信学会 ソサイエティ大会論文集,電子情報通信学会  1998.10 

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  • 焦点合わせの異なるレジストレーションとぼけ推定

    久保田彰, 児玉和也, 相澤清晴, 羽鳥光俊

    映像メディア処理シンポジウム資料,電子情報通信学会  1998.10 

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Awards

  • IEEE MMSP'12 Top 10% paper award

    2012.9   Quality-optimized Encoding of JPEG Images using Transform Domain Sparsification

    unichi Ishida, Gene Cheung, Akira Kubota, Antonio Ortega

  • 映像情報メディア学会 平成23年度丹羽高柳賞論文賞

    2012.5  

  • 画像符号化シンポジウム ベストポスター賞

    2011.10   画像符号化シンポジウム   ペナルティ関数法を用いた奥行マップの疎表現

    石田 淳一, チョン ジーン, 久保田 彰, オルテガ アントニオ

  • Top 10% paper award in MMSP'11

    2011.10   Depth Map Coding using Graph Based Transform and Transform Domain Sparsification

    Gene Cheung, Woo-shik Kim, Antonio Ortega, Junichi Ishida, Akira Kubota

  • フロンティア賞

    2007.12   映像メディア処理シンポジウム2007   スペクトル分解に基づいたシーン非依存型の視点内挿フィルタ

    久保田彰, 児玉和也, 羽鳥好律

  • フロンティア賞

    2005.12   映像メディア処理シンポジウム2005   3次元焦点ぼけ構造を用いて視点と焦点ぼけを操作する画像生成

    児玉和也, 久保田彰

  • 研究奨励賞

    2003.12   映像情報メディア学会   多視点・焦点画像の線形フィルタリングによる任意視点・焦点画像の生成

    久保田彰

  • 学術奨励賞

    2003  

  • 鈴木記念賞

    2001  

  • 鈴木記念賞

    2000.8   映像情報メディア学会   線形フィルタを用いた多焦点画像からの視覚効果処理-強調,流れ場,シフト処理-

    久保田彰

  • 学生論文賞

    1999.12   映像メディア処理シンポジウム1999   多焦点画像からの逆フィルタによる任意焦点画像の再構成

    久保田彰

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Research Projects

  • A study on quality improvement of three-dimensional visual media by a straightforward extension of conventional image restoration

    Grant number:26330215  2014.4 - 2017.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)  National Institute of Informatics

    KODAMA Kazuya, KUBOTA Akira

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    Grant amount: \4550000 ( Direct Cost: \3500000 、 Indirect Cost: \1050000 )

    Advanced three-dimensional visual media using enormous data such as multi-view images requires quality improvement beyond limitations on imaging devices. By analyzing redundancy of multi-view images on multi-focus images easily obtained from them, various linear filters for improving their quality were designed and their flexible extension was studied systematically. Actually, the proposed filters robustly work for quality improvement including not only multi-view image denoising but also view restoration. Moreover, good performance of the proposed method was shown by its implementation for dealing with enormous data of real multi-view images in real time.

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  • Signal transformation theory and its evaluation for multi-function and high-quality computational imaging

    Grant number:20700154  2008 - 2009

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Young Scientists (B)  Tokyo Institute of Technology

    KUBOTA Akira

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    Grant amount: \3900000 ( Direct Cost: \3000000 、 Indirect Cost: \900000 )

    This project developed a new image synthesis method that can reproduce visual effects using images that were captured under different capturing conditions. Simulation results showed the effectiveness of the developed method.

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  • 自由視点画像の生成のための、シーン構造に依存しない光線内挿法とその理論構築

    Grant number:18700169  2006 - 2007

    日本学術振興会  科学研究費助成事業  若手研究(B)  東京工業大学

    久保田 彰

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    Grant amount: \2700000 ( Direct Cost: \2700000 )

    多視点画像から自由視点画像を生成する際に対象シーンの奥行を推定しない方法を開発した。本手法は、多視点画像にフィルタを施すアプローチをとっている。このフィルタをシーンに依存することなく導出することに成功した。ただし、次の2点を仮定している:(1)奥行が2層である。(2)カメラの配置が円形である。(1)を仮定した場合は、それぞれに生じる対応点ずれを一種のぼけ作用としてとらえて、画像復元手法を適用し、繰り返し法の有限回における解として自由視点画像を生成した。(2)を仮定した場合は、対応点ずれを3次元の点広がり関数としてとらえて、逆フィルタ法を適用した。本手法は、コンピューターにて合成した画像に対して有効に動作することを確かめた。また、最適なカメラ配置やノイズ耐性についても調べた。その結果、カメラは奇数台がよく、ノイズ耐性はカメラ台数が多いほど向上することがわかった。また、ある台数以上で理論的には逆フィルタが安定にかつ一意に決定されることを示した。

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Intellectual property rights

  • 疎表現奥行き画像生成装置及びそのプログラム

    ジーン・チョン,アントニオ・オルテガ

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    Application no:特願2010-267265  Date applied:2010.11.30

    Announcement no:特開2012-119901  Date announced:2012.6.21

    Applicant (Organization):学校法人中央大学