Click and Share: a face recognition tool for the mobile community

Abstract: In this paper, we describe an Android based application for mobile devices that allows users to quickly and easily identify faces in pictures, recognizing persons, and, thus, sharing pictures with them. Each identified person matches against a contact registered in the phone directory, and, if no match is found, the detected face can be used for the creation of a new contact. We discuss how face recognition in a mobile setting increases the efficiency of the users while sharing content created with the mobile device, automatically suggesting the people identified in a photo or a video. We show the effectiveness of the approach through a user test on a photo sharing task, showing that it reduces the need for tedious, in particular on mobile devices, user input (e.g., compared to Facebook). By this means, we envision an increase of the quality of the user experience when interacting with the components of her social network.

Authors: S. Casti, F. Sorrentino, L. D. Spano, R. Scateni.
Click and Share: a face recognition tool for the mobile community.
IEEE International Conference on Image Processing (ICIP 2014), 1952-1956.
Parigi, Francia, Ottobre 2014.

CHROMAGRAM: A Real-time Chroma Key Application for Mobile Devices

Abstract: Chroma Key is a special-effects technique widely used by television and motion picture industries for image composition. This technique allows users to replace sections identified by a chosen colour in a multimedia stream (like a video or a photo) with another image or video stream. In this paper, we describe an easy-to-implement technique for the creation of an Android based application for mobile devices (like smartphones and tablets) that applies Chroma Key-based effects to the video stream coming from the device camera. We discuss the algorithm used to achieve the Chroma Key effect focusing on the computational performance and on the quality of its final result. Using a picture selected from the device gallery, this application makes possible the replacement of video stream background areas characterized by a chroma value with the chosen picture.

Authors: F. Corda, F. Sorrentino, R. Scateni.
CHROMAGRAM: A Real-time Chroma Key Application for Mobile Devices.
EuroGraphics Italian Chapter 2014 (short papers), 49-52.
Cagliari, Italia, Settembre 2014.

AR Turn-by-turn navigation in small urban areas and information browsing

Abstract: Navigation systems allow to discover cities and their urban areas easily and quickly, finding the shortest path to reach them and giving directions to users saving their time and energy. At present time, these systems are based over streets maps offered by the major mapping services like Tele Atlas, Navteq or OpenStreetMap. In recent years, thanks to the Google StreetView service it has been possible to discover main cities locations both indoor and outdoor. What is missing in this frame is the possibility to map small urban areas of small and medium sized cities, due to their lack of relevance for the big players. In this cities there could be very interesting areas for tourists. Example locations could be botanical gardens, archeological sites, protected natural areas among others. In this work we tried to set up a navigation system for limited extensions inside urban areas which permits to wander around and gives access to related information using augmented reality techniques. Due to the possible poor wireless coverage in these locations we designed an application that stores all required data on the user’s device, splitting the information in packages according to the chosen language. A key issue was to achieve good results combining all these features in a single device with a small display, overwhelming the constraints due to the mobile environment.

Authors: G. Cherchi, F. Sorrentino, R. Scateni.
AR Turn-by-turn navigation in small urban areas and information browsing.
EuroGraphics Italian Chapter 2014 (short papers), 37-40.
Cagliari, Italia, Settembre 2014.

Curvature-based blending of closed planar curves

Abstract: A common way of blending between two planar curves is to linearly interpolate their signed curvature functions and to reconstruct the intermediate curve from the interpolated curvature values. But if both input curves are closed, this strategy can lead to open intermediate curves. We present a new algorithm for solving this problem, which finds the closed curve whose curvature is closest to the interpolated values. Our method relies on the definition of a suitable metric for measuring the distance between two planar curves and an appropriate discretization of the signed curvature functions.

M. Saba, T. Schneider, K. Hormann, R. Scateni.
Curvature-based blending of closed planar curves.
Graphical Models, 76(5):263-272 (GMP 2014, Singapore, SN).
Elsevier, September 2014.