1,721,057 research outputs found
Documentazione tridimensionale dei manufatti di interesse storico-artistico della Garfagnana: la Chiesa di Santa Maria Assunta a Vitoio (Camporgiano, Lu)
No full textLa Chiesa di Santa Maria Assunta presso Vitoio (Camporgiano, Lu) Vitoio ha una lunga storia che è possibile rintracciare nelle pergamene antiche che testimoniano l’esistenza di un primigenio edificio, dedicato alla Vergine Maria e a San Pietro, fondata quasi al volgere dell’VIII secolo per volere del longobardo Toto. L’edificio, ricostruito nel periodo medievale, deve la sua compilazione attuale alle numerose attività di modificazione succedutesi nei secoli. Esternamente queste trasformazioni sono in parte leggibili negli elevati, non intonacati, dove sono evidenti le manomissioni dovute ai successivi interventi ed il cambiamento di tecniche costruttive e di materiali impiegati per l’edificazione. Ai fini di un approfondimento delle fasi evolutive dell’edificio, si è deciso di documentare l’apparato murario esterno e gli interni attraverso la creazione di un modello tridimensionale generato con tecniche di foto-modellazione e mediante 3D laser scanner. Tale metodologia di lavoro ha permesso di ottenere informazioni metricamente affidabili per eseguire valutazioni di carattere costruttivo e sullo stato di conservazione dell'edificio, costituendo così un supporto descrittivo visivamente e metricamente efficace
Documentazione del patrimonio architettonico e urbano mediante rilievo laser scanner 3D
No full textAt present the three-dimensional digital documentation of architectural, archaeological and landscape
heritage becomes of primary importance since – in increasingly short time and with reasonable costs
– it allows high-detailed representations with multiple uses. These three-dimensional materials can be
the support to prepare drawings aimed at projects for restoration, preservation and enhancement of
Cultural Heritage, even by latest real-time interactive representations. The most common techniques
for digital surveying are based on active sensors, which potentialities and limitations will be pointed
out in brief in this paper by presenting an illustrative case study of a survey carried out by means of 3D
laser scanner
Modelli digitali da Structure from Motion per la costruzione di un sistema conoscitivo dei portici di Bologna. Structure from Motion digital models to develop a cognitive system of the porticoes in Bologna
No full textLa fotogrammetria di nuova generazione si basa su processi fortemente automatizzati finalizzati a ottenere modelli poligonali, mappati con texture del colore apparente. Tuttavia per ottenere asset digitali 3D polifunzionali, in grado di documentare e illustrare efficacemente il patrimonio costruito, è necessario svolgere specifiche azioni per migliorare gli aspetti metrici, topologici e cromatici sintetizzati da tali rappresentazioni. Una recente ricerca sui portici di Bologna, finalizzata a costruire un sistema conoscitivo basato su modelli digitali 3D, ha consentito di mettere a punto un framework operativo capace di risolvere alcuni fra i principali problemi dei modelli mesh prodotti mediante SfM, ottimizzando i risultati ottenuti e valutando – da diversi punti di vista – l’affidabilità di queste tecniche alla scala urbanaNew generation photogrammetry is based on extremely automated processes used to obtain
polygonal models mapped with apparent colour textures. However, to obtain multifunctional 3D digital assets capable of documenting and successfully
illustrating built heritage specific actions have to be performed to improve the metric, topological and chromatic aspect synthesised by these representations. A recent study on the porticoes in Bologna was performed to create a cognitive system based on 3D digital models. The study made it possible to develop an operative framework capable of not only solving some of the main problems of mesh models produced using Structure from Motion, but also optimising the
results and assessing – from various angles – the reliability of these techniques at the urban scal
CULTURAL HERITAGE THROUGH 3D MODELS: THE PORTICOES OF BOLOGNA LA FRUIZIONE DEL PATRIMONIO MEDIANTE I MODELLI DIGITALI 3D: IL CASO DEI PORTICI DI BOLOGNA
No full textThe historic centre of Bologna is characterized by the presence of porticoes: the introduction of this architectural feature goes back to the thirteenth century, and is still present today for an extension of almost 40 km. Porticoed streets are then an important heritage of the town, that witness an unique architectural and artistic evolution of the city over the centuries: the constant presence of this architectural type forming a cultural, economic and aesthetic system made Bologna's porticoes valuable for its inclusion in 2006 in the Italian Tentative List of the UNESCO World heritage sites. A possible extensive documentation of this cultural complex is allowed by the recent advantages of IT, in particular photo-modelling tools, since they speed surveying activities, providing textured reliable 3D models and keeping in the meanwhile a low cost of the tools needed for data acquisition. The aim is not just bound to the creation of a virtual repository whose main purpose is fostering intervention on the historic buildings, ensuring their protection: the wider focus of 3D surveying activities is dissemination and sharing of digital contents within a vast audience
Ravenna’s Archaeological Heritage. Integration of techniques for accurate documentation through 3D digital models
No full textSince 1996 several monuments of Ravenna’s historical centre have been registered as UNESCO
sites due to the outstanding value of their mosaic art pieces, as well as the peculiar architectural features in
baptisteries, churches, mausoleums: they provide crucial evidence showing the transition from Ancient
Roman typologies to Late Antiquity buildings.
By testing the interaction between the 3d mapping technologies and the applications the entertainment, this
paper will explain the results of an interdisciplinary research project and its future potential, by illustrating the
methodology used to obtain reliable and multipurpose 3D models. The creation of a mapping database is the
central purpose of the operations carried out on captured data and such material is suitable for both the
interactive exploration using 3D devices such as Oculus VR as well as for an accurate documentation of the
state of conservation of relevant ancient buildings in Ravenna.
More specific technical points deal with fully exploiting image-based modelling tools based on Structure from
Motion (SfM) algorithms and render-to-texture solutions (baking in CG applications). In this context, the
typical automatic solutions implemented in the latest generation of photogrammetric software play a very
important role since they avoid time-consuming manual parameterization within the entertainment
applications. On the other hand, other problems concerning the full employment of 3D data from active and
passive sensors will be shown: the field of this methodology is called BRDF, and in particular splitting
apparent colour textures (from passive sensors) into a set of images providing the render engine with more
accurate and specific information to achieve higher photo-realism
A novel method for shadow removal and BRDF simulation of texture from SfM applications
No full textThe representation of colour and more in general optic behaviour of 3D digital assets has always been a complex matter, of primary importance especially when representing the descriptive features of archaeological and architectural heritage.
This topic involves different research fields, different ranging technologies (active and passive sensors) and different professional skills. In fact, time consuming techniques or expensive devices are not suitable for budgets and abilities that in general cannot be found in the field of documentation of Cultural Heritage. For this reason low-cost and rapid solution are in general most welcome, rather than sophisticated techniques that lead to reliable physical BRDF acquisition, with the disadvantage of being actually still very far from a true implementation in small or intermediate research projects, as well as in case of extensive documentation of archaeological areas.
The general purpose of this paper is the explanation of a pipeline aimed at converting apparent colour texture into diffuse maps starting from the output provided by Structure from Motion application, taking account of some case studies from historic centre of Ravenna.
A set of different materials, characterized by different optical behaviours, ranging from Lambertian surfaces to some dielectric specular materials have been surveyed using different devices (active and passive sensors) and then mapped with a set of different textures obtained from apparent colour. The workflow consists in a double data capture: on the one hand geometric aspects of archaeological remains (laser scanner and passive sensors for SfM applications), on the other hand a surveying of environmental illumination using HDR images.
This technique, developed in the frame of CGI and visual effects creation, is based on an extensive use of render-to-texture solutions (baking) implemented inside entertainment applications, whose function is to store indirect illumination solution from HDRI into (u,v) texturing system. This greyscale image provides an effective masking solution for a set of apparent colour textures of the same object resulting from different radiometric recovery.
Logistic aspects of the photographic campaign, frames pre-processing and texture post-processing form part of a pipeline aimed at converting apparent colour texture into a set of images able to generate a more natural and photo-realistic representation of 3D assets, since the typical “double shadow” effect from SfM generated models results mitigated
Chiuro laboratory: integration of workflows from digital survey to optimised 3D urban models for interactive exploration
Full text linkThe digital acquisition of Chiuro (Italy) is part of a research action of the still ongoing project “Le radici di una identità” (“An identity and its roots”), dealing with the documentation of the original urban structure of Chiuro, a small settlement located in northern Italy, whose interesting remains of mediaeval towers and Renaissance palaces are still well preserved. The paper focusses on the complete workflow developed by the group to create an explorative and implementable 3D digital model of the urban centre, constructed by a set of optimised mesh models. From the acquisition phase to geometric processing methodologies, different modelling strategies have been investigated to solve problems related to survey integration, and optimisation of the architectural digital assets. The main challenge is in fact the utilisation of the huge amount of data gathered during the previous surveying campaigns, providing a specific workflow to obtain an optimised 3D model. Moreover, the paper analyses some outputs: one is the storytelling of historical and cultural heritage in an attractive way, using game engines to visualise and give access to detailed digital contents to the general public
UNDERSTANDING ANCIENT DESIGN THROUGH SURVEY: EXAMPLES FROM HADRIAN’S VILLA
No full textThe Dipartimento di Architettura of the Alma Mater Studiorum - University of Bologna is carrying out a series of investigations on the Villa Adriana in Tivoli, in collaboration with the Soprintendenza Archeologia del Lazio e Dell’Etruria Meridionale, Italian and foreign Universities and higher education institutions and companies in the field of remote sensing, which have digitally acquired several pavilions of this important UNESCO site since 2013. In this paper we present briefly the first outcomes of numerous documentation campaigns aimed at solving some outstanding problems in relation with investigation lines concerning mixtilinear plan design and complex vaulted spaces. The latter, thanks to a complete digital surveying campaign, can be examined with an high level of accuracy that led to more reliable interpretation of vaulted systems conceived during Hadrianic age
DIGITALIZATION CULTURE VS ARCHAEOLOGICAL VISUALIZATION: INTEGRATION OF PIPELINES AND OPEN ISSUES
Full text linkScholars with different backgrounds have carried out extensive surveys centred on how 3D digital models, data acquisition and processing have changed over the years in fields of archaeology and architecture and more in general in the Cultural Heritage panorama: the current framework focused on reality-based modelling is then split in several branches: acquisition, communication and analysis of buildings (Pintus et alii, 2014). Despite the wide set of well-structured and all-encompassing surveys on the IT application in Cultural Heritage, several open issues still seem to be present, in particular once the purpose of digital simulacra is the one to fit with the “pre-informatics" legacy of architectural/archaeological representation (historical drawings with their graphic codes and aesthetics). Starting from a series of heterogeneous matters that came up studying two Italian UNESCO sites, this paper aims at underlining the importance of integrating different pipelines from different technological fields, in order to achieve multipurpose models, capable to comply with graphic codes of traditional survey, as well as semantic enrichment, and last but not least, data compression/portability and texture reliability under different lighting simulation
La gestione del colore nei modelli digitali per l'archeologia: il caso del Teatro Marittimo di Villa Adriana a Tivoli
No full textIl Teatro Marittimo è un edificio fra i più celebri dell’antichità classica ed è stato oggetto di innumerevoli rilievi che nel corso dei secoli ne hanno di volta in volta attestato lo stato di conservazione, i restauri e l'“ambientazione” all'interno del paesaggio architettonico e naturalistico della Villa Adriana.
Il rilievo del colore, al pari delle caratteristiche formali delle murature e della decorazione architettonica, ha costituito uno dei principali oggetti di interesse durante l’esperienza condotta sulla Villa da parte dei pensionnaires francesi (XIX e XX secolo). Mediante le restituzioni ad acquerello su tavole di grandi dimensioni, questi artisti hanno fornito un esempio che risulta tutt'oggi ineguagliato per eleganza espressiva ed uniformità dei metodi di rappresentazione. Questi ultimi sono stati soggetti ad una codifica in ambito archeologico che ha visto prevalere la componente analitica a discapito della suggestione pittorica che trapela degli envois, come attestano i rilievi della Villa di Rakob, Ueblacker e Hoffmann.
Fra gli studi recenti di carattere ricostruttivo, quelli condotti da Cinque e Adembri, hanno visto la reintroduzione del colore quale strumento essenziale per la trasmissione dell’immagine originaria dei sontuosi interni della dimora imperiale, caratterizzati da marmi policromi fra i più preziosi e ricercati dell’antichità (rosso, verde e giallo antico, serpentino, porfido, pavonazzetto).
I dati raccolti in occasione della recente campagna di rilevamento laser scanner e fotogrammetrico del Teatro Marittimo hanno fornito la base di partenza per ulteriori considerazioni sul rapporto colore - inteso come texture - e rovina. Test estensivi sull'ottimizzazione dei modelli e relative mappature hanno infatti permesso di raggiungere un duplice obiettivo: il primo consiste nel permettere ad un unico modello digitale foto-realistico di supportare una estesa gamma di scale di restituzione; il secondo è quello di rendere coerente l’importazione in uno stesso ambiente 3D di ulteriori modelli appartenuti alla decorazione architettonica originaria del Teatro Marittimo per eseguirne l'anastilosi virtuale. Tali frammenti, custoditi nelle collezioni di musei e magazzini dell’area archeologica, vennero asportati nel corso dei secoli e sono stati oggetto di rilevamenti digitali specifici finalizzati ad individuarne la posizione originaria.
L’ottenimento di restituzioni 3D scientificamente accurate, che al tempo stesso riuscissero ai colmare il divario comunicazionale fra rappresentazione tradizione e digitale, si articola in vari passaggi: in primo luogo l’analisi delle soglie computazionali ammissibili di modelli e relative texture, la segmentazione su base semantica, la realizzazione di copie a dettaglio ridotto correttamente parametrizzate, la mappatura delle normali, la correzione radiometrica di fotogrammi e texture del colore (sia delle strutture in situ che dei frammenti di trabeazione)
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