Kazuhiro Terajima The University of Tokyo 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656 Japan Kazuhiro_Terajima@ipc.i.u-tokyo.ac.jp Takashi Komuro The University of Tokyo 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656 Japan Takashi_Komuro@ipc.i.u-tokyo.ac.jp Masatoshi Ishikawa The University of Tokyo 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656 Japan Masatoshi_Ishikawa@ipc.i.u-tokyo.ac.jp We developed a system which performs 3D motion tracking of human's hand and fingers from images of a single high-frame-rate camera and that recognizes his/her typing motion in the air. Our templatematching-based method using hand textures reduces background effect and enables markerless tracking. In addition, use of a high-frame-rate camera enables recognition of rapid typing motion which is difficult to track using standard cameras. In order to realize realtime recognition, we developed hardware which parallelizes and accelerates image processing. As a result, we achieved real-time recognition of typing motion wi...