This paper reports on the design and implementation of BeThereNow, a public interactive information system where users are depicted immersed in various sceneries. The work is focused on the domain of info-tainment in public spaces using large displays and aims on short-time usage. The implemented system employs a mixed reality application through which users are informed about different sceneries and also create personalized digital postcards. This process is accomplished using computer vision algorithms in order to depict users and objects, while removing the background of the scene. Finally, the lessons learned from the long-term deployment of the system out-in-the-wild are presented, providing an insight on the users’ actions and reactions and feedback on future research directions.

This work regards fingertip contact detection and localization upon planar surfaces to provide interactivity in augmented displays implemented upon these surfaces, by projector-camera systems. In contrast to the widely employed approach where user hands are observed from above, lateral camera placement avails increased sensitivity to touch detection. An algorithmic approach for the treatment of the laterally acquired visual input is proposed and is comparatively evaluated against the conventional.

In this paper, a steerable, interactive projection display that has the shape of a disk is presented. Interactivity is provided through sensitivity to the contact of multiple fingertips and is achieved through the use of a RGBD camera. The surface is mounted on two gimbals which, in turn, provide two rotational degrees of freedom. Modulation of surface posture supports the ergonomy of the device but can be, alternatively, used as a means of user-interface input. The geometry for mapping visual content and localizing fingertip contacts upon this steerable display is provided, along with pertinent calibration methods for the proposed system. An accurate technique for touch detection is proposed, while touch detection and projection accuracy issues are studied and evaluated through extensive experimentation. Most importantly, the system is thoroughly evaluated as to its usability, through a pilot application that was developed for this purpose. We show that the outcome meets real-time performance, accuracy and usability requirements for employing the approach in human computer interaction.

An active field of research today is the technological enrichment of everyday activities using augmented reality and ambient intelligence technologies. To this end, augmenting dinner tables is a challenging task, requiring a high-quality user experience unobtrusively supporting and enhancing the user’s main goal: eating and socializing. This work presents an augmented restaurant table, facilitating customers’ ordering and enhancing their experience through entertainment and socialization features, as well as through interaction with physical objects placed upon the table surface.

Touchless remote interaction empowers users to interact with systems at a distance without the burden of actually coming to physical contact with any tangible object. The research presented in this paper focuses on motion-based interaction in public spaces through hand detection using Microsoft’s Kinect, in order to allow natural interaction in mid-air. The paper presents the development of a system that allows browsing and exploring large collections of multimedia information (images and videos).

This paper presents an innovative advergame installation for promoting the brand and products of a company producing Cretan rusks. The paper first presents some background and related work. Then, the requirements set towards creating the game are outlined, followed by concept creation and design decisions taken to meet these requirements, as well as a description of the user interface, gameplay and technical characteristics of the resulting game. The game has been installed with remarkable success in two different food exhibitions in key locations in Athens, Greece, where it has been played by more than 500 people of ages ranging from 2 to 76 years old. A large variety of qualitative and quantitative data were collected. The paper presents several findings stemming from these data. Additionally, changes made to the game as a result of the findings are presented, along with lessons learnt from the acquired experience.

A visual user interface providing augmented, multitouch interaction upon a non-instrumented disk that can dynamically rotate in two axes is proposed. While the user manipulates the disk, the system uses a projector to visualize a display upon it. A depth camera is used to estimate the pose of the surface and multiple simultaneous fingertip contacts upon it. The estimates are transformed into meaningful user input, availing both fingertip contact and disk pose information. Calibration and real-time implementation issues are studied and evaluated through extensive experimentation. We show that the outcome meets accuracy and usability requirements for employing the approach in human computer interaction.

The theme of this paper is an exhibition of prototypical interactive systems with subjects drawn from ancient Macedonia, named "Macedonia from fragments to pixels". Since 2010, the exhibition is hosted by the Archaeological Museum of Thessaloniki and is open daily to the general public. Up to now, more than 165.000 people have visited it. The exhibition comprises 7 interactive systems which are based on some research outcomes of the Ambient Intelligence Programme of the Institute of Computer Science, Foundation for Research and Technology - Hellas. The digital content of these systems includes objects from the Museum’s permanent collection and from Macedonia.

This paper presents a computer vision system that supports non-instrumented, location-based interaction of multiple users with digital representations of large-scale artifacts. The proposed system is based on a camera network that observes multiple humans in front of a very large display. The acquired views are used to volumetrically reconstruct and track the humans robustly and in real time, even in crowded scenes and challenging human configurations. Given the frequent and accurate monitoring of humans in space and time, a dynamic and personalized textual/graphical annotation of the display can be achieved based on the location and the walk-through trajectory of each visitor. The proposed system has been successfully deployed in an archaeological museum, offering its visitors the capability to interact with and explore a digital representation of an ancient wall painting. This installation permits an extensive evaluation of the proposed system in terms of tracking robustness, computational performance and usability. Furthermore, it proves that computer vision technology can be effectively used to support non-instrumented interaction of humans with their environments in realistic settings.

This paper presents an advergame installation for promoting the brand and products of a food company producing various types of traditional Cretan rusks. The paper first presents some background and related work. Then the requirements set towards creating the game are outlined, followed by concept creation and design decisions taken in order to meet these requirements, as well as a description of the user interface, gameplay and implementation characteristics of the resulting game. The game has already been installed with remarkable success in two different food exhibitions.