Italian Chapter Conference 2006

Permanent URI for this collection

https://diglib.eg.org/handle/10.2312/910

Browse

Now showing 1 - 20 of 40

Compressed SVG Representation of Raster Images Vectorized by DDT Triangulation
(The Eurographics Association, 2006) Battiato, S.; Greco, F.; Nicotra, S.; S. Battiato and G. Gallo and F. Stanco
This paper presents a portable compression algorithm applied to raster data images properly triangulated by using DDT (Data Dependent Triangulation). In particular the input source data are encoded to be rendered by standard SVG (Scalable Vector Graphics) engine. The proposed compression strategy works reducing the overall entropy implementing some heuristic strategies to properly re-code the redundancy inside the mesh representation. The compressed data are enclosed into an SVG player able to both decompress and show the original image. Results show the effectiveness of the approach.
Recovering 3D architectural information from dense digital models of buildings
(The Eurographics Association, 2006) Spinelli, A.; Ganovelli, F.; Montani, C.; Scopigno, R.; S. Battiato and G. Gallo and F. Stanco
In recent years the progress of 3D scanning technologies and the consequent growing commercialization of scanners opened a large spectrum of opportunities for many professionals. In particular, architects and engineers may access to a digital model of a building without having to model it using a CAD software. On the other hand, there are two important differences between the digitized and the handcrafted model. The first is the absence of interpretation. The digitized model is merely a set of polygons that describe, possibly in a very accurate manner, the scanned object. It does not provide the user with any other information about what a surface is (a wall, a window, an arch etc.) that, conversely, can be incorporated during the editing in a CAD session. The second difference is excess of realism. In the digitized models the are no planar walls, no right angles, no straight edges, simply because they are not, at the millimetric scale. Unfortunately, if a model must be used in a FEM simulation, for example, a CAD like model would be required. This paper describes an application framework and some techniques that have been implemented to help a non computer-graphics user in handling digital models of buildings acquired using 3D scanning. The techniques permit to visualize efficiently the models independently from their size, recover 3D information (measurements, sections, . . . ), extract geometric features and fit high level geometric primitives.
Maya Sun Simulation of Bosnian Gravestone Virtual Model
(The Eurographics Association, 2006) Rizvic, S.; Sadzak, A.; Avdagic, Z.; Chalmers, A.; S. Battiato and G. Gallo and F. Stanco
Bosnia and Herzegovina is very rich with cultural heritage sites. Perhaps the most famous of these are the stecaks; the monumental gravestones of Bosnian Heretic Christians. The orientation of the stecaks was important to the ancient Bosnians, Unfortunately, their orientation towards the sun has been changed when they were moved from their original locations to more secure sites at museums. This is particularly true of the stecak from Donje Zgosce, one of the most beautiful stecaks in B&H. Using high-fidelity graphics techniques we have created a detailed virtual reconstruction of this stecak and produced a sun simulation in Maya This enables archaeologists to be able to investigate the interaction of the light with the stecak s carvings as it may have appeared in 14th century.
A New Descreening Technique in the Frequency Domain
(The Eurographics Association, 2006) Battiato, S.; Stanco, F.; S. Battiato and G. Gallo and F. Stanco
In this paper a new algorithm to obtain a continuous tone image starting from a halftoned one is proposed. This descreening technique is based on Butterworth filtering in the frequency domain. It removes the pattern of the original screen leaving unchanged the colors in the image. The proposed algorithm ensures fast and effective results, and can be used also by non-qualified operators.
Topological Descriptor for CAD Models with Inner Cavities
(The Eurographics Association, 2006) Symonova, O.; Dao, M.-S.; Amicis, R. De; Ucelli, G.; S. Battiato and G. Gallo and F. Stanco
The current work introduces an algorithm for constructing Reeb graph for CAD models and their inner cavities. The nodes of the graph represent areas of the manifold of the model where topological changes occur. Edges of the graph encode information about connections between such areas. The outline for the topological graph matching is given for detection of graph (sub)isomorphism. The proposed Reeb graph structure can be used as a descriptor of CAD models in the retrieval process.
A study on textures and their perceptual visual dimensions as application for flexible and effective scientific visualization
(The Eurographics Association, 2006) Taponecco, F.; S. Battiato and G. Gallo and F. Stanco
The use of textures is fundamental in several areas of Computer Graphics, Computer Vision and Image Processing. In this work, we focus on their main relevant attributes, in order to define and design textures as effective visual representations for use in scientific visualization. We concentrate on the problem of visualizing complex multivariate and multi-dimensional datasets as well as in synthesizing multi-fields and temporal evolution of vectorial datasets visualization. Textures features, such as directionality, color and shape are particularly suited for use in a synthesis algorithm, and they serve as effective seed primitives, which can incorporate many visual dimensions for intuitive and flexible data mapping and encoding. As special application, we propose a level-based visualization approach, with a special focus on systematic layering of information for scientific datasets.
Shape Reconstruction with Uncertainty
(The Eurographics Association, 2006) Papaleo, L.; Puppo, E.; S. Battiato and G. Gallo and F. Stanco
This paper presents a general Surface Reconstruction framework which encapsulates the uncertainty of the sampled data, making no assumption on the shape of the surface to be reconstructed. Starting from the input points (either points clouds or multiple range images), an Estimated Existence Function (EEF) is built which models the space in which the desired surface could exist and, by the extraction of EEF critical points, the surface is reconstructed. The final goal is the development of a generic framework able to adapt the result to different kinds of additional information coming from multiple sensors.
3D CT Segmentation for Clinical Evaluation of Knee Prosthesis Operations
(The Eurographics Association, 2006) Battiato, S.; Bosco, C.; Farinella, G. M.; Impoco, G.; S. Battiato and G. Gallo and F. Stanco
In surgical knee replacement, the damaged knee joint is replaced with artificial prostheses. An accurate clinical evaluation must be carried out before applying knee prostheses to ensure optimal outcome from surgical operations and to reduce the probability of having long-term problems. Useful information can be inferred from CT scans of the knee area, that can be used to estimate the stress that will be acting on the prosthesis being implanted. This information can be exploited to tailor the prothesis to the patient s anatomy. We present some ideas for a system intended to help surgeons in evaluating the post-operative outcome of knee prosthesis implantation. We also show some preliminary results about the 3D segmentation of CT data, that is the main activity of our lab in the project.
3D Input devices integration in CAD environment
(The Eurographics Association, 2006) Bruno, F.; Caruso, G.; Muzzupappa, M.; S. Battiato and G. Gallo and F. Stanco
Virtual Reality (VR) technologies are becoming commonly used tools in the product development process, starting from the styling review in the conceptual design phase, until to the Digital Mock-up (DMU) validation in the advanced stages of the design process. What has not yet been sufficiently investigated is the possibility to interact with the DMU directly inside the CAD environment using 3D input devices. Although few CAD systems, like CATIA V5, have an additional module to support VR devices, in most cases it is still necessary to customize the application to obtain the functionalities desired by the user. The present paper discusses difficulties and advantages related to the integration of VR techniques and 3D input devices in CAD systems. The work has been conducted analyzing and testing the potentialities of the Unigraphics NX3 CAD environment and implementing a software plug-in that allows the user to perform such interaction tasks employing 3D input devices.
GPU based direct illuminance values computation for interactive lighting CAD
(The Eurographics Association, 2006) Selmo, D.; Musante, F.; Rossi, M.; S. Battiato and G. Gallo and F. Stanco
In this work we focus our attention on real-time direct illuminance values computation using dedicated 3D graphics hardware compatible with OpenGL 2 standard. Our method works with real light intensity distribution measured for lighting fixtures by enconding it in a texture for GPU data comunication. Illuminance values are reprensented in real-time by using a perceptual based colour scale. Illuminance computation is limited to direct light. This is not a severe limitation for exterior and road lighting design, and nevertheless it is a useful project parameter for interior lighting design too.
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. Stanco
The 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).
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. Stanco
This 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.
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. Stanco
This 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).
Sub-part correspondence using structure and geometry
(The Eurographics Association, 2006) Biasotti, S.; Marini, S.; S. Battiato and G. Gallo and F. Stanco
The paper describes a method for recognizing similar sub-parts of objects described by 3D polygonal meshes. The innovation of our method is the coupling of structure and geometry in the matching process. First of all, the structure of the shape is coded in a graph where each node is associated to a sub-part of the shape. Then, the matching between two shapes is approached using a graph-matching technique relying upon a geometric description of each sub-part.
Designing a Virtual Reality Game for the CAVE
(The Eurographics Association, 2006) Livatino, S.; Agerbech, V.; Johansen, A.; Johansen, B.; S. Battiato and G. Gallo and F. Stanco
Virtual Reality has for many years been a technology which has stagnated in application and software development for games. The applications available for VR environments have increased but they mostly remain related to scientific purposes while computer games in VR are still being developed and only show a part of their actual potential. The game industry has begun to see the possibilities of VR games in a near future with the implementation of some popular games to a CAVE system. However, a full immersion VR solution still remains uncommon and expensive. This paper aims to demonstrate the potential of VR games, and in particular games for the CAVE, now that affordable solutions are close to reach as more powerful hardware is available at low price. The focus is also on the methodology to be pursued while designing a VR game. Results were encouraging and tests performed on a first prototype demonstrates system feasibility.
VTK4AR: An Object Oriented Framework for Scientific Visualization of CAE Data in Augmented Reality
(The Eurographics Association, 2006) Bruno, F.; Caruso, F.; Ferrise, F.; Muzzupappa, M.; S. Battiato and G. Gallo and F. Stanco
In the last ten years many Augmented Reality (AR) applications for Scientific Visualization have been developed, attesting the effectiveness of this technique for data visualization and interaction. In all these applications, a software framework for scientific visualization was used to process data to be visualized, while an AR system was employed to display these data within an AR context. Hence, everyone who intended to approach the development of such applications should become necessarily familiar with the scientific visualization framework and the augmented reality one. This is of course an hurdle for the applications development, and the idea behind this work is exactly to provide a software framework that simplifies the development of such applications. With this in mind, we extended an existing and powerful open source library for scientific visualization (VTK) with few but useful classes for the interfacing with an existing AR library (ARToolKit) to easily handle the video see-through and the video-tracking functionalities. The resulting software tool, called VTK4AR, can be considered as an all in one software framework specific for scientific visualization in AR. Moreover, since it is built on top of VTK, it will be possible to employ a wide range of visualization techniques in many application fields. In particular, it has been tested in two AR applications: one for displaying data relative to a CFD simulation of a flow past a helmet, and another for displaying the forming error obtained prototyping an ankle support with the incremental forming technique.
Solutions to 3D Building Reconstruction from Photographs
(The Eurographics Association, 2006) Farinella, G. M.; Mattiolo, G.; S. Battiato and G. Gallo and F. Stanco
The 3D model reconstruction of buildings from uncalibrated photographs allows new useful Computer Graphics and Computer Vision applications. In this paper we survey some solutions proposed in literature and in commerce. The common and different methodology are reported and described. Finally we try to address the 3D reconstruction problem of architectural scenes presenting our solution: BolBol. We demonstrate our reconstruction process and some results obtained applying BolBol to the modeling of real buildings.
Shape Comparison and Deformation Analysis in Biomedical Applications
(The Eurographics Association, 2006) Colantonio, S.; Moroni, D.; Salvetti, O.; S. Battiato and G. Gallo and F. Stanco
In this paper, we present a method for comparing shapes and analyzing deformations of 3D image objects. This method is based on the definition of an object model based on multi-source 3D images. Elective application cases of the proposed method consist of the analysis of deformable anatomical structures, useful to support medical diagnosis in routine clinical practice. In particular, preliminary aspects are discussed of a study case regarding heart dynamics.
Multi-resolution Morphological Representation of Terrains
(The Eurographics Association, 2006) Danovaro, E.; Floriani, L. De; Vitali, M.; Papaleo, L.; S. Battiato and G. Gallo and F. Stanco
Mesh-based terrain representations provide accurate descriptions of a terrain, but fail in capturing its morphological structure. The morphology of a terrain is defined by its critical points and by the critical lines joining them, which form a so-called surface network. Besides being compact, a morphological terrain description supports a knowledge-based approach to the analysis, visualization and understanding of a terrain dataset. Moreover, because of the large size of current terrain data sets, a multi-resolution representation of the terrain morphology is crucial. Here, we address the problem of representing the morphology of a terrain at different resolutions. The basis of the multi-resolution terrain model, that we call a Multi-resolution Surface Network (MSN), is a generalization operator on a surface network, which produces a simplified representation incrementally. An MSN is combined with a multi-resolution mesh-based terrain model, which encompasses the terrain morphology at different resolutions. We show how variable-resolution representations can be extracted from an MSN, and we present also an implementation of an MSN in a compact encoding data structure.
A Message-Based Annotation System for Collaborative Design Review
(The Eurographics Association, 2006) Witzel, M.; Conti, G.; Amicis, R. De; S. Battiato and G. Gallo and F. Stanco
The paper illustrates a shared annotation mechanism developed within a collaborative virtual environment for design review. This represents one of the first prototypes being developed within the European Project IMPROVE and it has been designed to be used within two distinct industrial scenarios: automotive and architectural design. The key feature of the system is that its functionalities (modelling, rendering, tracking) are distributed across a network of computers performing specific tasks and that the communication among these takes place through a standardised data message exchange. This paper shows the effectiveness of this approach by focusing on the implementation of the distributed annotation feature.

Browse

Browsing Italian Chapter Conference 2006 by Issue Date

Results Per Page

Sort Options