Photometric HDR video for visual adaptation models. - Keita Hirai; Toshiya Nakaguchi; Norimichi Tsumura; Yoichi Miyake (SIGGRAPH Research Posters, 2006)

Measurement and Modeling of Viewing-Condition-Dependent Spatio-Velocity Contrast Sensitivity Function. - Keita Hirai; Norimichi Tsumura; Toshiya Nakaguchi; Yoichi Miyake (CIC, 2007)

Compensation for projected image under dim illumination with CIECAM02. - Sayuri Kamimigaki; Keisuke Taki; Keita Hirai; Shoji Yamamoto; Norimichi Tsumura; Toshiya Nakaguchi; Yoichi Miyake (CGIV/MCS, 2008)

The relationship between ambient illumination and psychological factors in viewing of display Images. - Takuya Iwanami; Ayano Kikuchi; Takashi Kaneko; Keita Hirai; Natsumi Yano; Toshiya Nakaguchi; Norimichi Tsumura; Yasuhiro Yoshida; Yoichi Miyake (Color Imaging: Displaying, Processing, Hardcopy, and Applications, 2009)

SV-CIELAB: Video Quality Assessment using Spatio-Velocity Contrast Sensitivity Function. - Keita Hirai; Jambal Tumurtogoo; Ayano Kikuchi; Toshiya Nakaguchi; Norimichi Tsumura; Yoichi Miyake (CIC, 2009)

Real reproducing of 3D appearance with multi-projectors and cameras. - Sayuri Kamimigaki; Shoji Yamamoto; Keita Hirai; Norimichi Tsumura; Toshiya Nakaguchi; Yoichi Miyake (CIC, 2009)

Adaptive Ambient Illumination Based on Color Harmony Model. - Ayano Kikuchi; Keita Hirai; Toshiya Nakaguchi; Norimichi Tsumura; Yoichi Miyake (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2009)

Measurement and Modeling of Chromatic Spatio-Velocity Contrast Sensitivity Function and its Application to Video Quality Evaluation. - Keita Hirai; Toshiaki Mikami; Norimichi Tsumura; Toshiya Nakaguchi (CIC, 2010)

Video Quality Assessment Using Spatio-Velocity Contrast Sensitivity Function. - Keita Hirai; Jambal Tumurtogoo; Ayano Kikuchi; Norimichi Tsumura; Toshiya Nakaguchi; Yoichi Miyake (IEICE Trans. Inf. Syst., 2010)

Color Signal Estimation in High Dynamic Range Scenes. - Keita Hirai; Shoji Tominaga (CIC, 2011)

Psychological Effects of Ambient Illumination Control and Illumination Layout While Viewing Various Video Images. - Takuya Iwanami; Ayano Kikuchi; Keita Hirai; Toshiya Nakaguchi; Norimichi Tsumura; Yoichi Miyake (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2011)

A LUT-based Method for Recovering Color Signals from High Dynamic Range Images. - Keita Hirai; Shoji Tominaga (CIC, 2012)

Metal-dielectric object classification by combining polarization property and surface spectral reflectance. - Shoji Tominaga; Hideki Kadoi; Keita Hirai; Takahiko Horiuchi (Color Imaging: Displaying, Processing, Hardcopy, and Applications, 2013)

Estimation of bispectral matrix for fluorescent objects. - Shoji Tominaga; Keita Hirai; Takahiko Horiuchi (CVCS, 2013)

Investigation of Japanese Onomatopoeias as Features for SHITSUKAN-Based Image Retrieval. - Yuxing Wu; Keita Hirai; Takahiko Horiuchi (ISM, 2013)

Estimation of Two Illuminant Spectral Power Distributions from Highlights of Overlapping Illuminants. - Nguyen Thuc Dieu Hang; Takahiko Horiuchi; Keita Hirai; Shoji Tominaga (SITIS, 2013)

An LED-Based Spectral Imaging System for Surface Reflectance and Normal Estimation. - Keita Hirai; Tetsushi Tanimoto; Kazuya Yamamoto; Takahiko Horiuchi; Shoji Tominaga (SITIS, 2013)

Spectral analysis of omnidirectional color signals in natural scenes. - Shoji Tominaga; Daiki Watanabe; Keita Hirai; Takahiko Horiuchi (Color Imaging: Displaying, Processing, Hardcopy, and Applications, 2014)

Measurement and Modeling of Bidirectional Characteristics of Fluorescent Objects. - Shoji Tominaga; Keita Hirai; Takahiko Horiuchi (ICISP, 2014)

An HDR Spectral Imaging System for Time-Varying Omnidirectional Scene. - Keita Hirai; Naoto Osawa; Takahiko Horiuchi; Shoji Tominaga (ICPR, 2014)

Color image recovery system from printed gray image. - Jiqiang Lin; Takahiko Horiuchi; Keita Hirai; Shoji Tominaga (SSIAI, 2014)

Visual Quality Improvement of Color-Embedded Gray Images for a Reversible Color-to-Gray Algorithm. - Takahiko Horiuchi; Jiqiang Lin; Keita Hirai (AECIA, 2015)

Development of a Dynamic Relighting System for Moving Planar Objects with Unknown Reflectance. - Ryosuke Nakahata; Keita Hirai; Takahiko Horiuchi; Shoji Tominaga (CCIW, 2015)

Photometric and geometric measurements based on multi-primary image projector. - Keita Hirai; Daisuke Irie; Takahiko Horiuchi (CVCS, 2015)

Construction of Manga Materials Database for Analyzing Perception of Materials in Line Drawings. - Yuma Saito; Keita Hirai; Takahiko Horiuchi (CIC, 2015)

Bispectral Interreflection Estimation of Fluorescent Objects. - Shoji Tominaga; Keiji Kato; Keita Hirai; Takahiko Horiuchi (CIC, 2015)

Perceptual Dependencies in Fabric Appearance between Texture and Color. - Takafumi Katsunuma; Keita Hirai; Takahiko Horiuchi (Measuring, Modeling, and Reproducing Material Appearance, 2016)

Modeling and Estimation for Surface-Spectral Reflectance of Watercolor Paintings. - Shoji Tominaga; Shingo Dozaki; Yukiko Kuma; Keita Hirai; Takahiko Horiuchi (Measuring, Modeling, and Reproducing Material Appearance, 2016)

Measuring Spectral Reflectance and 3D Shape Using Multi-primary Image Projector. - Keita Hirai; Ryosuke Nakahata; Takahiko Horiuchi (ICISP, 2016)

Spectral Image Analysis of Florescent Objects with Mutual Illumination. - Shoji Tominaga; Keiji Kato; Keita Hirai; Takahiko Horiuchi (CIC, 2016)

Video Smoke Removal Based on Smoke Imaging Model and Space-Time Pixel Compensation. - Shiori Yamaguchi; Keita Hirai; Takahiko Horiuchi (CCIW, 2017)

Interactive Object Surface Retexturing using Perceptual Quality Indexes. - Keita Hirai; Wataru Suzuki; Yoshimitsu Yamada; Takahiko Horiuchi (Material Appearance, 2017)

Appearance Decomposition and Reconstruction of Textured Fluorescent Objects. - Shoji Tominaga; Keiji Kato; Keita Hirai; Takahiko Horiuchi (Material Appearance, 2017)

Analysis of Material Representation of Manga Line Drawings using Convolutional Neural Networks. - Takahiko Horiuchi; Yuma Saito; Keita Hirai (CIC, 2017)

Appearance Reconstruction of Fluorescent Objects for Different Materials and Light Source. - Shoji Tominaga; Keiji Kato; Keita Hirai; Takahiko Horiuchi (CIC, 2017)

Correlation Analysis between Wood Eigen Textures and Perceptual Qualities. - Yoshimitsu Yamada; Keita Hirai; Takahiko Horiuchi (CIC, 2017)

Fabric Appearance Control System for Example-Based Interactive Texture and Color Design. - Takafumi Katsunuma; Keita Hirai; Takahiko Horiuchi (ACM Trans. Appl. Percept., 2017)

A General Method for Estimating Fluorescent Donaldson Matrices. - Shoji Tominaga; Keita Hirai; Takahiko Horiuchi (Material Appearance, 2018)

Reversible Color-to-Gray Mapping with Resistance to JPEG Encoding. - Takahiko Horiuchi; Xu Wen; Keita Hirai (SSIAI, 2018)

High-Dynamic-Range Spectral Imaging System for Omnidirectional Scene Capture. - Keita Hirai; Naoto Osawa; Motoki Hori; Takahiko Horiuchi; Shoji Tominaga (J. Imaging, 2018)

Haze Transfer Between Images Based on Dark Channel Prior. - Koushirou Maeda; Keita Hirai; Takahiko Horiuchi (CCIW, 2019)

Makeup Skin Appearance Reproduction by Spectral Projection Mapping. - Hiroki Shirasawa; Keita Hirai; Takahiko Horiuchi (CCIW, 2019)

Constructing glossiness perception model of computer graphics with sounds. - Takumi Nakamura; Keita Hirai; Takahiko Horiuchi (Material Appearance, 2019)

Appearance Reconstruction of Mutual Illumination Effect between Plane and Curved Fluorescent Objects. - Shoji Tominaga; Keita Hirai; Takahiko Horiuchi (Material Appearance, 2019)

Appearance Reconstruction of Fluorescent Objects Based on Reference Geometric Factors. - Shoji Tominaga; Keita Hirai; Takahiko Horiuchi (CIC, 2019)

Estimation of Layered Ink Layout from Arbitrary Skin Color and Translucency in Inkjet 3D Printer. - Junki Yoshii; Shoji Yamamoto; Kazuki Nagasawa; Wataru Arai; Satoshi Kaneko; Keita Hirai; Norimichi Tsumura (CIC, 2019)

Construction of facial emotion database through subjective experiments and its application to deep learning-based facial image processing. - Tomoyuki Takanashi; Keita Hirai; Takahiko Horiuchi (Image Processing: Algorithms and Systems, 2019)

Advances in Cross-Spectral Iris Recognition Using Integrated Gradientface-Based Normalization. - Maulisa Oktiana; Khairun Saddami; Fitri Arnia; Yuwaldi Away; Keita Hirai; Takahiko Horiuchi; Khairul Munadi (IEEE Access, 2019)

BTF Image Recovery based on U-Net and Texture Interpolation. - Naoki Tada; Keita Hirai (Material Appearance, 2020)

Estimation of Layered Ink Layout to reproduce desired Translucency of skin in Inkjet 3D Printer using deep neural network trained with synthetic simulated data. - Kensuke Fukumoto; Kazuki Nagasawa; Wataru Arai; Kunio Hakkaku; Satoshi Kaneko; Keita Hirai; Norimichi Tsumura (CIC, 2020)

Image-Based Measurement of Structural Color using Spectral Camera. - Kazuki Iwata; Hiroki Shirasawa; Keita Hirai (CIC, 2020)

Investigating Effects of Visual and Auditory Adaptation on Metallic Material Appearance. - Takumi Nakamura; Yagi Daichi; Kuangzhe Xu; Toshihiko Matsuka; Keita Hirai (CIC, 2020)

Spectral Estimation of Multiple Light Sources based on Highlight Detection. - Shoji Tominaga; Keita Hirai; Takahiko Horiuchi (CIC, 2020)

Color Discrimination Experiments using Metameric ipRGC Stimuli. - Masaya Ohtsu; Akihiro Kurata; Keita Hirai (Color Imaging: Displaying, Processing, Hardcopy, and Applications, 2021)

Testing Machine Learning Models for Individual Emotion Estimation from Indoor Environment Data. - Isao Kurebayashi; Nobuyoshi Komuro; Keita Hirai (ICCE-TW, 2021)

A Study on Time Series Analysis of Environmental Data for Predicting Emotional Conditions. - Koshiro Maeda; Isao Kurebayashi; Nobuyoshi Komuro; Keita Hirai (LifeTech, 2021)

Video Smoke Removal from a Single Image Sequence. - Shiori Yamaguchi; Keita Hirai; Takahiko Horiuchi (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2021)

Hand authentication from RGB-D video based on deep neural network. - Ryogo Miyazaki; Kazuya Sasaki; Norimichi Tsumura; Keita Hirai (3D Imaging and Applications, 2022)

Fabrication of a Human Skin Mockup with a Multilayered Concentration Map of Pigment Components Using a UV Printer. - Kazuki Nagasawa; Shoji Yamamoto; Wataru Arai; Kunio Hakkaku; Chawan Koopipat; Keita Hirai; Norimichi Tsumura (J. Imaging, 2022)

Evaluating the Influence of ipRGCs on Color Discrimination. - Masaya Ohtsu; Akihiro Kurata; Keita Hirai; Midori Tanaka; Takahiko Horiuchi (J. Imaging, 2022)

Mental-state estimation model with time-series environmental data regarding cognitive function. - Isao Kurebayashi; Koshiro Maeda; Nobuyoshi Komuro; Keita Hirai; Hiroo Sekiya; Makoto Ichikawa (Internet Things, 2023)