About me

• 
CV

• I am a Ph.D student at Toyota Technological Institute (Japan)． I'm now at Intelligent Information Media Lab working with Prof. Normichi Ukita. (E-mail: sd23501 [at] toyota-ti.ac.jp)

  My research interest includes action recognition, especially in the context of group activity understanding.

  I've published papers on joint attention estimation (ICCV2023), group activity feature learning (CVPR2024, CVIU2026), and people grouping (ICCV2025).

• 2021: Dropped out of Department of Advanced Science and Technology, Faculty of Engineering, Toyota Technological Institute (for early admission of a graduate school)
• 2023: Received Master of Engineering degree from Department of Advanced Science and Technology, Toyota Technological Institute (graduate at the top of the class)
• 2023/04-2024/03: Doctor of Philosophy in Engineering, Department of Electronics and Information Engineering, Toyota Technological Institute
• 2024/04-2024/09: Long-term internship at Hokkaido Nippon-Ham Fighters (analyst)
• 2024/10-present: Doctor of Philosophy in Engineering, Department of Electronics and Information Engineering, Toyota Technological Institute
• 2025/04-2025/06: Visitor at Idiap Research Institute
• 2026/04-2026/09: JSPS Research Fellowship for Young Scientists (DC2)

Selected Publications

• Chihiro Nakatani, Hiroaki Kawashima, Norimichi Ukita
Human-in-the-loop Adaptation in Group Activity Feature Learning for Team Sports Video Retrieval

Computer Vision and Image Understanding, vol.263, pp. 104577, 2026.
Special issue on "Computer Vision for Sports and Winter Sports".

• Kaname Yokoyama, Chihiro Nakatani, Norimichi Ukita
Dynamic Group Detection using VLM-augmented Temporal Groupness Graph

Proc. of IEEE International Conference on Computer Vision (ICCV2025), Oct., 2025. (acceptance rate = 24.0%)

• Chihiro Nakatani, Hiroaki Kawashima, Norimichi Ukita
Learning Group Activity Features Through Person Attribute Prediction

Proc. of IEEE Conference on Computer Vision & Pattern Recognition (CVPR2024), June, 2024. (acceptance rate = 23.6%)

• Chihiro Nakatani, Hiroaki Kawashima, Norimichi Ukita
Interaction-aware Joint Attention Estimation Using People Attributes

Proc. of IEEE International Conference on Computer Vision (ICCV2023), Oct., 2023. (acceptance rate = 26.15%)

• JST ASPIRE Kyoto Workshop Poster Award. (2025)

• International travel grant offered by the Telecommunications Advancement Foundation. (2024)

• International Conference Research Presentation Award from IEEE Nagoya Branch. (2024)

• International exchange grant offered by Tateishi Science and Technology Foundation. (2024)

• Scholarship offered by The Toyoaki Scholarship Foundation. (2023-2025)

• Scholarship offered by The Toyota Technological Institute. (2023-2025)

• SICE Outstanding Student Award. (March, 2023)

• Scholarship offered by The Toyota Scholarship Foundation. (2018-2021)

Work Experience

• Playbox (Machine Learning Engineer)

Remote; 2025/09-2025/12.

• Hokkaido Nippon-Ham Fighters (Analyst)

Hokkaido Japan; 2024/04-2024/09. Long-term internship

• OptFit Corporation (Server Side Engineer)

Remote; 2020. Part-time job

• Activate Data Corporation (Machine Learning Engineer)

Remote; 2019. Part-time job