1,720,971 research outputs found
Applications to manage PLY format files
No full textIn this technical report are described two applications developed to manage PLY files. The first application is a converter from ascii PLY format file to binary PLY format file and vice versa. The second appliction is a converter from PIF format file to PLY format fil
Detailed 3D Modelling of Castles
No full textDigitally documenting complex heritage sites such as castles is a desirable yet difficult task with no established framework. Although 3D digitizing and modelling with laser scanners, Photogrammetry, and computer aided architectural design (CAAD) are maturing, each alone is inadequate to model an entire castle in details. We present a sequential approach that combines multiple techniques, each where best suited, to capture and model the fine geometric detail of castles. We provide new contributions in several areas: an effective workflow for castle 3D modelling, increasing the level of automation and the seamless integration of models created independently from different data sets. We tested the approach on various castles in Northern Italy and the results demonstrated that it is effective, accurate, and creates highly detailed models suitable for interactive visualization. It is also equally applicable to other types of large complex architectures
Dati RGB e Laser Scanner per la Modellazione di Piccoli Oggetti Complessi
No full textLa realizzazione di modelli 3D digitali di beni architettonici o storici e la relativa visualizzazione al computer è oggi uno dei campi di ricerca a cui viene rivolto maggior interesse per le innumerevoli applicazioni pratiche che possono derivare da questi studi. Ancor oggi rimane incerto il problema fondamentale di come si possa unire al dato 3D, proveniente dal laser scanner, l’informazione di colore dell’oggetto rappresentato. Sebbene esistano in commercio alcuni software dedicati alla texturizzazione del modello 3D a partire da immagini digitali, i risultati non sempre risultano soddisfacenti, soprattutto nel caso di geometrie particolarmente complesse. Mentre infatti nel caso di scansioni di oggetti con sviluppo prevalentemente piano si ottengono buoni risultati, superfici caratterizzate da elevati valori di curvatura favoriscono l’insorgenza di discontinuità e imperfezioni nella texture finale inaccettabili. In questo articolo si vogliono esporre i risultati di un’esperienza condotta in collaborazione tra il Cirgeo (Centro Interdip. di Ricerca dell’Università di Padova) e l’ITC (Istituto Trentino di Cultura) nell’ambito della produzione di modelli 3D, con texture, relativi ad oggetti di piccole dimensioni, mediante integrazione di tecniche laser scanner e fotogrammetria digitale applicata ad immagini ad alta risoluzione. I risultati ottenuti nella riproduzione virtuale degli oggetti considerati sembrano soddisfacenti dal punto di vista delle texture, la cui qualità appare comparabile se non superiore a quanto prodotto dai software di uso commerciale
Optical measurement techniques for the digital preservation, documentation and analysis of cultural heritages
No full textNowadays the digital documentation and 3D modeling of Cultural Heritage objects and sites is receiving much more attention. This is due from one side to the large amount of technologies and data available for fast, detailed and quick documentation and from the other side to the great interest of restorators and archaeologists towards instruments able to provide innovative inspections and diagnostic results. The correct selection, combination and integration of the available techniques requires great experience and the need to combine them comes from the complexity of some heritage structures and the lack of a single method capable of providing satisfactory results in all measuring conditions. In this work we report our use of consumer digital cameras, range sensors and infrared thermography data for the documentation of heritage objects. The objective is to give an overview of the different techniques and the used methodology for the digital recording of detailed objects, monuments and large structures
Digital preservation, documentation and analysis of paintings, monuments and large cultural heritage with infrared technology, digital cameras and range sensors
No full textThe digital documentation and 3D modelling of Cultural Heritage monuments and sites is receiving great attention in the last years. There is a large variety of technologies for 3D surveying purposes and generally a technique is chosen according to the project requirements, operator experience, budget and location constraints. Digital images and range sensors (laser scanner or stripe projection systems) are generally the most used technologies used to virtually reconstruct the whole geometry of the studied heritage. The combination of the two recording methods has demonstrated to be an efficient way of 3D modeling as no technique by itself is able to provide accurate 3D results in all the applications and in short time. Other data are becoming nowadays pretty common and important for a more deep documentation and investigation of heritages, i.e. image data coming from the light spectrum outside the visible range. In this work, we present how we derive geometric 3D models of heritage structures by means of close-range photogrammetry or range sensors while extra information acquired with infrared cameras are used for texture mapping purposes and other studies. Data obtained from all those instruments are registered and fused together for documentation reasons, historical studies, restoration plans and visualization purposes
Integration of non-invasive techniques for documentation and preservation of complex architectures and artworks
No full textThe digital documentation of cultural heritage is receiving much attention in the last few years and 3D modeling of objects or sites is one of the main research topics in this field. Many improvements have been done in the generation of digital models of cultural heritage, concerning range sensors and image based modeling. But there are still a lot of open questions and problems in deciding which technique should be employed in which situation. While in the past years, when high level of detail was required, range sensors were usually preferred to image data, nowadays, due to the considerable algorithm improvements and increase of automation in the image-based modeling process, the digitization of cultural heritage based on close-range photogrammetry covers a more and more important role. Furthermore, new sensors, working outside the visible spectrum, are nowadays available for cultural heritage documentation and preservation. Therefore the integration of all these digital information would leave to much more detailed, interesting and valuable results. In this article we present the most common technique for heritage surveying and 3D modeling and we report examples related to the frescoed Romanino’s Loggia located in the Buonconsiglio Castle (Trento, Italy)
THE PRIMM METHOD FOR TEACHING PROGRAMMING: EXPERIMENTATION AND VALIDATION
No full textThe project "Algorithmically: from problem-solving to computer science" is a research-action project
funded and carried out in the academic year 2022-23 by the Scientific High School “Leonardo da Vinci”
(Trento, Italy), in collaboration with the University of Trento. The goal of the project was to validate the
PRIMM (Predict, Run, Investigate, Modify, Make) methodology for teaching programming, which
subverts the traditional approach based on early program writing. Instead, students are encouraged to
read and understand segments of code before writing their own, emphasising a "reading before writing"
approach. The teaching experimentation was applied in 5 second classes of the high school, with 4
control group classrooms (190 students and 9 classes). To understand the effectiveness of this new
methodology, the design was a Pre-Test and Post-Test, with a test aiming at understanding skills and
knowledge and another based on the Intrinsic Motivation Inventory (IMI). The first iteration of this
experimental teaching approach provides promising results but also indicates the need for refining the
sample and some methods and procedures. However, there are significant findings:
1 PRIMM methodology proved to be slightly more effective than traditional teaching methods in
terms of learning.
2 PRIMM methodology promotes Competence Perception, and its relationship with Competence
Perception is confirmed, positive, and significant.
3 Competence Perception correlates with better computer science grades, so PRIMM might bring
higher marks in Computer Sciences.
The PRIMM approach’s integration into computer science teaching thus appears promising, but
additional research and iterations are needed to optimise its effectiveness
Experiences and considerations in image-based modeling of complex architectures
No full textNowadays image-based modeling is receiving much attention and many applications require precise and photo-realistic 3D models. The camera calibration and orientation phases are key steps in the 3D modeling process. If these phases are not accurately performed, there will be some errors in the final model and for some applications low accuracy results are not accepted. The goal of this work is to investigate the influence of wrong camera parameters or bad image configuration in object reconstruction. The analysis is performed with a bundle adjustment solution perturbing the interior camera parameters and using different network configurations. We analyze the effects of wrong focal length and principal point as well as absent distortion parameters with images acquired under typical project configurations. Finally we report some examples of 3D modeling of complex architectures where the theoretical considerations cannot always be fulfilled
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