Photometric inconsistency on a mixed-reality face

A mixed-reality face (MR face) is a mosaic face with real and virtual facial parts, presented by overlaying a virtual facial part on a real face using mixed-reality techniques. An MR face is an effective means to improve communication in mixed-reality space by restoring the eye expressions lost when wearing HMDs. Photometric registration between the real and virtual parts is important because our eyes are very sensitive, even to small changes in human faces. However, efforts to achieve perfect 'physical' photometric registration on an MR face are not feasible in an ordinary MR space. Therefore, it is essential to clarify the sensitivity of our eyes to the photometric inconsistencies on an MR face, and to concentrate on resolving them. In this paper, we first present the results of a systematic experiment that evaluated our sensitivity to the photometric inconsistencies on an MR face. Then, a technique to resolve the inconsistency and an experimental system to demonstrate the effectiveness of an MR face are described.