As an increased number of people work from home or need to communicate with someone working in a different place, effective communication over long distances becomes important. When people collaborate to design documents on a whiteboard, they spend more time gesturing and pointing than actually drawing. Iconic gestures to help to clarify details, and facial expressions to signify attention and understanding. In order to communicate over large distances, conveying gesture and gaze information is as important as conveying the diagram. Most communications systems only convey intentional behaviors. However, unintentional behaviors such as gesture and gaze are also necessary for accurate communication.
Problem
The problem is how to convey gesture and gaze information in a way that is intuitive to working with a diagram. A shared virtual workspace on a computer where both parties can change the diagram and view in real time the other’s actions allows the document to be shared, but the document is the only information conveyed. An auditory link is some help, but visual cues are also necessary. The subset of the shared workspace problem that I am working on deals with collaborative diagrams on a whiteboard.
One metaphor for communicating this information is the clearboard approach. If two people are drawing on and gesturing toward a clear pane of glass between them, they can easily view their partner’s actions. This can be simulated using a camera and electronic whiteboard with projector. A camera will capture and invert the images, which will then be projected onto the screen. The advantage of clearboard is that it is easy to follow gesture and gaze cues. The project will involve implementing the clearboard approach using the electronic whiteboard and camera.
The camera to be used can be controlled with a set of C packages called TCL Vision. This allows the program to move the camera, zoom in and out, and return a matrix of the colour values that the camera is seeing. In order for the diagram and spatial information to be correct for the clearboard metaphor, this image must be flipped on the vertical axis before it is projected.
The electronic whiteboard allows input by drawing directly on the board with a stylus. This information is stored in a matrix and then projected onto the board, so it appears that anything drawn by the stylus was drawn directly onto the board.
One solution would be to have two electronic whiteboards with two cameras that send diagram and user information to the opposite whiteboard.
