A Tabletop System Using Infrared Image Recognition for Multi-user Identification

Abstract

Abstract. Many tabletop systems have been developed to facilitate face-to-face collaboration and work at small meetings. These systems often require users to attach sensors to their bodies to identify their positions, but attaching a sensor to one's body can be bothersome and annoying, and user position and posture may be restricted depending on where the sensor is attached. We have proposed a technique for estimating user position in a tabletop system by image recognition and implemented a tabletop system having a user position identification function incorporating the proposed technique. This technique first obtains touch points and hand-area information from touch operations performed by the user, and establishes an association between the touch points and hand from those positional relationships. Since the direction in which a hand is extended can be derived from that hand's touch information, the position of the user of the touch points belonging to that hand can be estimated. As part of this study, we also implemented a photo-object manipulation application, which has a function for orienting a photo object to face the user based on the results of the above user-position estimation technique. We performed an experiment to evaluate the position identification rate, and found that the proposed technique could identify user position with high accuracy. In a tabletop system, objects can be oriented in various ways by touch gestures performed by multiple users, which means that a user may find it difficult to understand the text or photo of an object that is currently not facing in the user's direction. In response to this problem, several techniques have been developed to identify user positions by attaching sensors to chairs or the users themselves [8], [9], [10], and these technique are used to automatically modify the orientation of an objects according to the position of the user manipulating that objects. For example, Diamond Touch [9], registers beforehand each user and the user's position by having each user sit on a conductive sheet for user-identification purposes, and uses this information to determine the position of the user whenever the user is identified. However, identifying user position by attaching sensors to chairs or people can be troublesome, and time must be devoted to learning how to use sensor equipment. User posture may also be restricted depending on where the sensor is attached. KeywordsOn the other hand, research has been performed on an interactive system that extracts images of body extremities using image recognition technology so that physical movements performed by the user can be used as input operations [11]. This kind of interactive system using image recognition negates the need for wearing a sensor thereby enabling users to use the system in a free and natural manner.We propose a technique for estimating user position by image recognition in a tabletop system and construct a tabletop system incorporating this technique. This technique negates the need for wearing a sensor ...

Multi-touch Tabletop System Using Infrared Image Recognition for User Position Identification

“…Finally, Suto et al [15], [16] created a multi-touch tabletop system that identifies user position by image recognition using an FTIR touch panel and external infrared light. They investigated the accuracy of recognizing multi-touch gestures with this system.…”

“…We have previously created a tabletop system using infrared image recognition for user position identification [15], [16]. In this paper, we describe a multi-touch tabletop system using infrared image recognition for user position identification that expands upon the previous system configuration and software.…”

Fingers of a Hand Oscillate Together

“…DiamondTouch [5] used capacitve coupling through the body to separate hands (requiring users to sit in specific transmitter seats). Suto et al [16] use an optical system to estimate finger identity from user position. Medusa [1] used proximity sensors to detect the orientation of arms and assign touch points by projecting the arm orientation to the touch region.…”

Multi-Touch Tabletop System Using Infrared Image Recognition for User Position Identification

“…In the case of a multi-touch table used for simultaneous interactions by multiple users, being able to identify the users who are touching the table and their positions can facilitate group work, education and training [ 4 ], medical training and treatment planning [ 11 ], security control for machines, games, etc., that take participants into account. Suto et al [ 12 ] presented a multi-touch tabletop system to identify user position using an infrared camera. By performing background differencing on the captured infrared images when a user performs a touch operation on the system, the tabletop image can be classified into three types of areas: the touch areas, the hand area, and the background itself.…”

“…A vision-based method following the third approach that detects parts of a user’s body and recognizes user actions outperforms the other methods in terms of ease of human motion and flexibility of system development. Suto’s tabletop system [ 12 ] has a feature to detect the user position and multi-touch gestures by a vision-based approach with one infrared camera.…”