Towards Reliable Computer Vision-based Tangible User Interfaces

A major obstacle in the development of computer visionbased interfaces is the uncertainty in the image data. Guaranteeing reliable program behavior while the inputs cannot be relied upon to take any specific values is desirable but extremely challenging. We have experimented with various strategies for addressing this problem in a controlled environment and have identified some that we find promising. Using visual tags, we encode object attributes, capture them with a camera, and read them. The test applications are implemented as Macromedia Director movies with Lingo scripting, while the image analysis module is implemented in C++ as a Lingo Xtra. We conclude that evaluation through rigorous experimentation and testing is a suitable approach for discovering techniques that work well and the conditions that maximize the chances for optimal performance.