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Item Multi-modal Digitalization of Cultural Heritage Artifacts(The Eurographics Association, 2014) Stanco, Filippo; Gallo, Giovanni; Cannata, Giovanna; Lombardo, Marcella; Andrea GiachettiObjects made of different media, paintings, marbles, clay and wooden objects, textiles etc., form the historical collections of most of the middle to medium sized Museums in Italy. This variety poses difficult challenges to these institutions when they face the digitalization of part of their patrimony. This paper provides a report of an ongoing inter-disciplinary experimental program for a digitalization effort to be carried out by one of such institution. Through the discussion of the digitalization of different objects obtained with the use and integration of different techniques we illustrate some of the lessons learned in transferring to the final intended users the graphical tools and the know-how previously acquired in a research laboratory.Item 3D Scene Comparison using Topological Graphs(The Eurographics Association, 2007) Paraboschi, L.; Biasotti, S.; Falcidieno, B.; Raffaele De Amicis and Giuseppe ContiNew technologies for shape acquisition and rendering of digital shapes have simplified the process of creating virtual scenes; nonetheless, shape annotation, recognition and manipulation of both the complete virtual scenes and even of subparts of them are still open problems. In this paper we deal with the problem of comparing two (or more) object sets, where each model is represented by an attributed graph. We will define a new distance to estimate the possible similarities among the sets of graphs and will validate our work using the shape graph [BGSF06].Item Use of Shader Technology for Realistic Presentation of Train Prototypes in Virtual Reality(The Eurographics Association, 2006) Gironimo, G. Di; Papa, S.; S. Battiato and G. Gallo and F. StancoThe aim of the paper is to make up a virtual showroom and work-through of a train model in order to allow railway companies showing new trains prototypes, in phase of concept, and present their new design in more exhaustive way than simply technical documentation. The possibility of applying Virtual Reality (VR) methodologies to make a scene more realistic as possible is a great advantage for the effectiveness of the presentation, in order to increase their competitivity. Shader technology allows the programmers to have control over shape, appearance (such as colour, lighting, reflection) and animation of objects, in order to make very realistic real-time rendering. In the paper the authors describe the use of shader technology in Virtual Design 2 (VD2) for realistic presentation of train prototypes in VR. The software VD2 is an extensive tool that allows following many phases of product development, from the creation of showroom for realistic presentations supporting shader technology to the assembly simulation or ergonomics analysis. Moreover, the possibility of interfacing with a wide range of input/output devices and the possibility to access to the API made this software to be chosen for Virtual Reality applications in the VR laboratory of the Competence Center for the Qualification of Transportation Systems founded by Campania Region (www.centrodicompetenzatrasporti.unina.it).Item A Natural and Effective Calibration of the CyberGlove(The Eurographics Association, 2006) Partipilo, S.; Felice, F. De; Renna, F.; Attolico, G.; Distante, A.; S. Battiato and G. Gallo and F. StancoThis work addresses the calibration of the CyberGlove, a device which provides information about the position and attitude in space of all the components of the user hand in a haptic system for the fruition of digital 3D contents by blind people. A realistic haptic interaction requires a reliable detection of user movements and a good calibration of the device to account for size and articulation capability of the specific hand. At the same time the application of interest calls for a calibration procedure that should be executable in a natural and straightforward way by every user. The two methods provided by the CyberGlove software are not suitable for these purposes: one is very simple and fast but produces quite imprecise results while the other is effective and accurate but involves a complex and cumbersome trial-and-error process not suited for general users. The proposed method aims to reach satisfactory results using a intuitive and simple approach. The user is asked to assume with his hand several pre-defined poses, each supplying the sensors output associated to known joints angles. Combining these data with the constraints derived by the anatomical structure of the hand it is possible to evaluate the values of the two parameters, gain and offset, that drive the digitalization of the sensor output. This process, in spite of its simplicity, has provided satisfactory results in several experimental sessions, enabling a realistic and reliable mirroring of user movements in the virtual space.Item Automatic Generation of Synthetic Retinal Fundus Images(The Eurographics Association, 2014) Fiorini, S.; Biasi, M. De; Ballerini, L.; Trucco, E.; Ruggeri, A.; Andrea GiachettiThis study aims to generate synthetic and realistic retinal fundus colour images, similar in characteristics to a given dataset, as well as the values of all morphological parameters. A representative task could be, for example, the synthesis of a retinal image with the corresponding vessel tree and optic nerve head binary map, measurement of vessel width in any position, fovea localisation and so on. The presented paper describes the techniques developed for the generation of both vascular and non-vascular regions (i.e. retinal background, fovea and optic disc). To synthesise convincing retinal backgrounds and foveae, a patch-based algorithm has been developed; model-based texture synthesis techniques have also been implemented for the generation of realistic optic discs and vessel networks. The validity of our synthetic retinal images has been demonstrated by visual inspection and quantitative experiments.Item Unambiguous Analysis of Woman Breast Shape for Plastic Surgery Outcome Evaluation(The Eurographics Association, 2006) Farinella, G. M.; Impoco, G.; Gallo, G.; Spoto, S.; Catanuto, G.; S. Battiato and G. Gallo and F. StancoThis paper reports a multidisciplinary research between computer science and plastic and reconstructive surgery. In particular, a new method is proposed to unambiguously define a geometric partitioning of a large thoracic area including the breast mound. The new technique uses only well-defined anatomical points, defined and selected by surgeons. A simple sequence of geometric operations is performed to partition the breast surface into four anatomic subunits, according to clinically derived breast meridian and equator lines. Using this breast shape partition, useful measurement can be extrapolated on 3D model data set. Our method has been validated on a number of breast 3D models acquired by means of a commercial scanner on real clinical cases collected by Istituto Nazionale dei Tumori in Milan (INT).Item Tracking the Evolution of Rainfall Precipitation Fields Using Persistent Maxima(The Eurographics Association, 2016) Biasotti, Silvia; Cerri, Andrea; Pittaluga, Simone; Sobrero, Davide; Spagnuolo, Michela; Giovanni Pintore and Filippo StancoIn this paper we propose a novel methodology for tracking the maxima of rainfall precipitation fields, whose changes in time may give interesting insights on the evolution of storm. Our approach is based on a topological analysis of rainfall data allowing for the extraction of the most prominent, and hence meaningful, rainfall field maxima. Then, an ad-hoc bottleneck matching is used to track the evolution of maxima along multiple time instances. The potential of our method is exhibited through a set of experiments carried out on a collection of observed punctual rainfall data and radar measurements provided by Genova municipality and Regione Liguria.Item Building Morphological Representations for 2D and 3D Scalar Fields(The Eurographics Association, 2010) Comic, Lidija; Floriani, Leila De; Iuricich, Federico; Enrico Puppo and Andrea Brogni and Leila De FlorianiAscending and descending Morse complexes, defined by the critical points and integral lines of a scalar field f defined on a manifold domain D, induce a subdivision of D into regions of uniform gradient flow, and thus provide a compact description of the morphology of f on D. We propose a dimension-independent representation for the ascending and descending Morse complexes, and we describe a data structure which assumes a discrete representation of the field as a simplicial mesh, that we call the incidence-based data structure. We present algorithms for building such data structure for 2D and 3D scalar fields, which make use of a watershed approach to compute the cells of the Morse decompositions.Item Selective Rasterized Ray-traced Reflections on the GPU(The Eurographics Association, 2016) Kastrati, Mattias Frid; Goswami, Prashant; Giovanni Pintore and Filippo StancoRay-tracing achieves impressive effects such as realistic reflections on complex surfaces but is also more computationally expensive than classic rasterization. Rasterized ray-tracing methods can accelerate ray-tracing by taking advantage of the massive parallelization available in the rasterization pipeline on the GPU. In this paper, we propose a selective rasterized raytracing method that optimizes the rasterized ray-tracing by selectively allocating computational resources to reflective regions in the image. Our experiments suggest that the method can speed-up the computation by up to 4 times and also reduce the memory footprint by almost 66% without affecting the image quality. We demonstrate the effectiveness of our method using complex scenes and animations.Item User Interaction Feedback in a Hand-Controlled Interface for Robot Team Tele-operation Using Wearable Augmented Reality(The Eurographics Association, 2017) Cannavò, Alberto; Lamberti, Fabrizio; Andrea Giachetti and Paolo Pingi and Filippo StancoContinuous advancements in the field of robotics and its increasing spread across heterogeneous application scenarios make the development of ever more effective user interfaces for human-robot interaction (HRI) an extremely relevant research topic. In particular, Natural User Interfaces (NUIs), e.g., based on hand and body gestures, proved to be an interesting technology to be exploited for designing intuitive interaction paradigms in the field of HRI. However, the more sophisticated the HRI interfaces become, the more important is to provide users with an accurate feedback about the state of the robot as well as of the interface itself. In this work, an Augmented Reality (AR)-based interface is deployed on a head-mounted display to enable tele-operation of a remote robot team using hand movements and gestures. A user study is performed to assess the advantages of wearable AR compared to desktop-based AR in the execution of specific tasks.