In the current digital age, the adoption of natural interfaces between humans and machines is increasingly important. This trend is particularly significant in the education sector where interactive tools and applications can ease the presentation and comprehension of complex concepts, stimulate collaborative work, and improve teaching practices. An important step towards this vision, interactive whiteboards are gaining widespread adoption in various levels of education. Nevertheless, these solutions are usually expensive, making their acceptance slow, especially in countries with more fragile economies. In this context, we present the low-cost interactive whiteboard (LoCoBoard) project, an open-source interactive whiteboard with low-cost hardware requirements, usually accessible in our daily lives, for an easy installation: a webcam-equipped computer, a video projector, and an infrared pointing device. The detection software framework offers five different Pointer Location algorithms with support for the Tangible User Interface Object protocol and also adapts to support multiple operating systems. We discuss the detailed physical and logical structure of LoCoBoard and compare its performance with that of similar systems. We believe that the proposed solution may represent a valuable contribution to ease the access to interactive whiteboards and increase widespread use with obvious benefits. 1. Introduction Over the past decades, the computing power evolution has been remarkable, but human computer interaction (HCI) is still being realized, in most cases, through the traditional keyboard and mouse. The future of HCI should rely more on the use of natural interfaces, such as haptic, speech, and gestures. In particular, the use of natural interfaces through Interactive Whiteboards (IWs) in education environments can ease the presentation and comprehension of complex concepts, allow collaborative work between teachers and students and improve pedagogical practices. Although there are wide ranges of commercial IW solutions, they are generally expensive and difficult to afford and implement by a large number of education institutions. The main goal of this project consists in developing an open source software-based IW solution, based on usually accessible hardware in our daily lives, that is, a video projector, a laptop with a webcam, and an Infra-Red (IR) pointing device. The LoCoBoard [1] prototype uses computer vision algorithms for processing captured images through the webcam and interpret the user interactions. Each developed algorithm tries to
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