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1.
Three-dimensional (3D) digital preservation aims at generating 3D models of objects that have cultural or scientific value. It allows realistic visualization of objects through virtual museums or scientific applications, and the restoration of the preserved object in case of natural wear or accidents. This work contributes to this research area by presenting a method to improve color texture quality of 3D models obtained from color and depth images of a laser scanner. Although this device offers precise depth information, the resulting color information is still poor and limits the generation of realistic textures. Our approach is to capture photographs of the object with a high-resolution digital camera and use them to generate a new color texture for the 3D model. Our work proposes a practical technique, easy to replicate, to generate high quality textures for 3D models from photographs. The method is composed by three main steps: (1) calibration of the image acquisition devices; (2) data acquisition; and (3) texture generation. In this paper, we detail our color texture generation method and apply it on the digital preservation of many artworks made by native Brazilians (indians) from the Wauja and Karaja communities. These indigenous communities are acknowledged as great ceramic artists, each bearing their own main themes, using a very rich symbolism in their paintings. Their artworks represent important aspects of the native South American culture and their digital preservation is motivated by three main reasons: (1) their fragility; (2) the paintings loose their original appearance with time; and (3) the possibility of extinction of these communities. We present several results of preserved artworks with enhanced quality realistic texture maps. Also, we present a methodology to analyze the quality and accuracy of texture maps. The resulting 3D models can be visualized through a tool we developed to support the virtual exhibit of 3D preserved heritage.  相似文献   

2.
Many important pieces of sculpture are located in exposed sites where they are open to chemical and physical attack by atmospheric agents. In some cases outdoor sculpture is now reaching a critical condition where the cohesion of the material of construction is almost lost. In these circumstances we face a stark choice between removing the sculpture to a safer environment or allowing its destruction. The removal of sculpture from its original site is an emotive issue and it is clearly not acceptable to simply leave a void where the original was located. The obvious solution is to replace the original with a replica. This presents a range of problems since we must achieve a sympathetic and accurate replica without any damaging contact occurring to the original object. The use of a laser scanner combined with the latest manufacturing techniques presents a potential solution to the need for recording and non-contact replication. The aim of this paper is to highlight a case study involving the non-contact replication of two decayed marble sculptures at the Garden Temple of Ince Blundell Hall on Merseyside.  相似文献   

3.
Since 2005, Outstanding Universal Value (OUV) is the standard by which United Nations Educational Scientific and Cultural Organization (UNESCO) evaluates world cultural heritage site suitability. The sites worthy of UNESCO preservation as well as the parameters used to demonstrate OUV are diverse. Our study focused on the uniquely distinguished rural landscape sites and the OUV parameter of integrity. Integrity however, is an elusive concept for which UNESCO provides no definitional protocol, and for which the scientific community objects to a static or pure historical interpretation. Given this, our work aims to analyse the concept of integrity and how it can be used to preserve the heritage of rural landscapes. After reviewing the UNESCO approach, we focused on the international scientific debate on the meaning and application of integrity. We designed and conducted a comparative study of UNESCO rural landscapes selected from the 2011 World Heritage List. Documents describing the historical, rural, and agro-ecological features of each of the fourteen rural sites were analysed. From this, several historical and ecological parameters were chosen as “values to have” and several socio-economic and management parameters were chosen as “values to maintain” to assess the integrity of each landscape. Our results found integrity to be a value of both cultural and natural landscapes and that it is key to site identity. We demonstrated that UNESCO assigns a high value to the following parameters: historical features, traditional crops and local products, land-use and agricultural practice permanence, and the presence of architecture related to agricultural activity. Finally, we found the relationship between culture and nature to characterize best the integrity of a rural landscape, rather than nature or culture alone.  相似文献   

4.
The Minerva of Arezzo is an ancient bronze statue located at the Museo Archeologico in Florence and currently under repair at the Restoration Centre of the Soprintendenza Archeologica of the Tuscany Region. We assembled a complete three-dimensional (3D) digital model of the Minerva before the restoration started. More 3D models will be produced to keep track of the variations that occurred during the restoration process, up to the final acquisition of the form of the restored artwork. The modelling of the Minerva will be the focal point of an ambitious “Minerva Project” that involves the integration of data from other sources in a 3D digital model of the object. Besides this, the project is aimed at showing how 3D techniques can be used to design useful and easily manageable new tools for the diagnostics of archaeological objects. 3D measurements have been realized by means of a high-resolution laser scanner developed at National Institute for Applied Optics (INOA). The instrument is composed of commercial low-cost components in order to be competitive with the very expensive commercial devices. Besides this, our scanner is supported by an efficient and flexible software developed by Consiglio Nazionale delle Ricerche (CNR) that supports all the post-processing phases of a 3D scanning session (range data alignment, merge and simplification).  相似文献   

5.
A number of software solutions based on the Structure-From-Motion (SFM) and Dense Multi-View 3D Reconstruction (DMVR) algorithms have been made recently available. They allow the production of high quality 3D models by using unordered image collections that depict a scene or an object from different viewpoints. In this work, we question the quality of the data produced by a commercial SFM-DMVR software. An Ottoman monument located in the region of Xanthi, Greece has been selected as a case study. We attempted to quantify the quality of the SFM-DMVR data in relation to the data produced by a Time-of-Flight terrestrial 3D range scanner. We have implemented a number of comparisons between different parts of the monument in order to assess the mesh deviations and the reconstruction's accuracy. In order to further ensure the validity of our evaluation phase, we performed additional distance measurements between feature points on the monument's surface by using a total station and empirical measurements. The applicability of the SFM-DMVR method was questioned by creating a complete 3D digital replica of the monument.  相似文献   

6.
In the field of Cultural Heritage, image analysis represents an indispensable practice for restorers to collect information about the state of preservation of monuments and artifacts and plan restoration interventions. In addition, during the last two decades, the wide spread of remote sensing technologies and the possibility to build 3D reality-based models of artifacts allow the extension of image analysis to 3D environments. In this context, the purpose of this contribution is to show the results of investigations held in order to provide a methodology for the automatic detection of deteriorated areas within architectures and artifacts using colour images as a field of examination. Using both 2D and 3D segmentation approaches, our methodology aims at speeding and efficiently performing the automatic detection of deteriorated zones within Cultural Heritage and therefore segment 3D digital models acquired using different survey technologies. Within our investigations, we selected case studies concerning recurrent deteriorations, such as, for example, detachments, cracks and chromatic alterations; we run them both to manual and to automatic recognition and selection tests, in order to compare the results obtained using these approaches and evaluate the reliability of the automatic one. Results comparison included computational and user time, quantification of the deteriorated area error between manual and automatically detected zones. Additional parameters characterizing the specific type of deteriorations were also computed for each case study. Comparison between the automatic and the manual procedure showed that the automatic detection is faster and reliable in all our selected case studies, with evident improvements in the efficient evaluation of the entity and extension of deteriorated areas on 3D geometry.  相似文献   

7.
On many occasions, the graphic information handled by people working in the cultural heritage sector is still bidimensional. Layouts showing elevations and cross sections are the most widespread tools. However, there is an increased need for carefully detailing the complexity of valuable sites with an improved accuracy. This implies the measuring and handling of three-dimensional data, using both commercial and turn-key hardware and software solutions. Taking the usual traditional process as a reference, in the present paper a new effective methodology for carrying out computer assisted delineation of layouts from cultural heritage sites, using 3D digital models, is described. The proposed procedure has been tested in five intervention projects on representative churches within the “Merindad de Aguilar de Campoo” medieval area, in the north of Spain.1 This area has the largest collection of Romanesque art in the world, and is currently under European Heritage Site and World Heritage Site declaration process by the UNESCO.  相似文献   

8.
One essential approach in preserving architectural heritage is the documentation of 3D geometries and surface textures of historic buildings. For example, precise colour information, excluding lighting effects, is an intrinsic property of the surface materials of building interiors and exteriors. However, while colour information has been recorded for small sample areas, it has not been accurately documented on the scale of entire building surfaces. This is critical, because building materials decay and their colours fade with time. The goal of this project is to develop a method to assist in recording and documenting the chromatic information of interiors and exteriors of historic buildings with low cost and high efficiency. The method takes advantage of emerging high dynamic range imaging (HDRI) technology, which can store rich information about colour and illumination through digital photography. By recording the colour information, in addition to the geometry and texture information obtained through other existing technologies, we can achieve more complete documentation for architectural heritage. In this paper, we discuss an overview of the problem and present our algorithms for utilizing computer vision techniques to retrieve chromatic information of historic buildings. We also present and discuss our experiments and results of applying our method to studies of lab objects and the Hall of Supreme Harmony in the Forbidden City, Beijing.  相似文献   

9.
In this article we present our global approach to the problem of accurate 3D measurement and reconstruction of 3D works of art using a calibrated multi-camera system. In particular, we illustrate a simple and effective adaptive technique for the self-calibration of CCD-based multi-camera acquisition systems with minimum a-prior information. We also propose a general and robust approach to the problem of close-range partial 3D reconstruction of objects from stereo-correspondences. Finally, we introduce a method for performing an accurate patchworking of the partial reconstructions, based on 3D curve matching.  相似文献   

10.
UNESCO world cultural heritage sites, in particular landscapes, impose several land use restrictions and consequently impact the welfare of various stakeholders. As the preservation of the denomination implies costs, it is of utmost importance to identify and value stakeholders’ preferences. This paper applies discrete choice experiments to the Alto Douro Wine Region, classified by UNESCO as world heritage site. The results suggest a clear hierarchy of attributes. In addition, the introduction of both socioeconomic variables and interaction terms provides useful insights on systematic heterogeneity of preferences with interesting directions for heritage safeguarding.  相似文献   

11.
Cheb relief intarsia is one of the most significant artistic techniques used in the early and middle baroque furniture manufacturing. The origin of this exceptional technique is closely tied to the city of Cheb and in a wider perspective, similarly to rondocubism or cubism applied in architecture; it is a branch of decorative arts distinctive just only for Czech lands. Here we report on the findings made on the basis of non-destructive X-ray micro computed tomography (μCT) analysis for determination of the condition and characteristics of the inner structures of an original plate of Cheb relief intarsia. The results of this analysis not only helped to clarify the manufacturing process itself, but also contributed to aim the future actions of the effective intarsia conservation in regard to the spreading internal cracks and defects in the plate discovered by μCT analysis.  相似文献   

12.
Patrick Petitjean 《Minerva》2008,46(2):247-270
The World Federation of Scientific Workers (WFScW) and UNESCO share roots in the Social Relations of Science (SRS) movements and in the Franco-British scientific relations which developed in the 1930s. In this historical context (the Great Depression, the rise of Fascism and the Nazi use of science, the social and intellectual fascination for the USSR), a new model of scientific internationalism emerged, where science and politics mixed. Many progressive scientists were involved in the war efforts against Nazism, and tried to prolong their international commitments into peacetime. They contributed to the establishment of the WFScW and of UNESCO in 1945–1946. Neither the WFScW nor UNESCO succeeded in achieving their initial aims. Another world emerged from the immediate post-war years, but it was not the world fancied by the progressive scientists from the mould of scientific internationalism. The aim of this article is to follow the path from the Franco-British networks towards the establishment of the WFScW and UNESCO; from an ideological scientific internationalism towards practical projects. It is to understand how these two bodies came to embody two different scientific internationalisms during the Cold War.
Patrick PetitjeanEmail:
Patrick Petitjean   is “Chargé de Recherches” at the CNRS, Paris. He is an historian of science and belongs to the laboratory REHSEIS (Recherches Epistémologiques et Historiques sur les Sciences Exactes et les Institutions Scientifiques). He has co-edited Science and Empires—Historical Studies about Scientific Development and European Expansion (Dordrecht: Kluwer Academic Publishers, 1992); and Les Sciences colonials—figures et institutions (Paris: Orstom éditions, 1996). He has recently published some contributions on Unesco’s first years: Petitjean, P., Zharov, V., Glaser, G., Richardson, J., de Padirac, B. and Archibald, G. (eds), Sixty Years of Sciences at UNESCO, 1945–2005 (UNESCO, Paris, 2006). He is currently working on the history of international scientific relations from the 1930s to the 1950s, and on the influence of the science and society movements upon the Science Division of UNESCO.  相似文献   

13.
Exhibition of objects such as paintings or historical artefacts often involves a common problem: the objects presented are unique, delicate and, therefore, very valuable. On the other hand, these objects should be made accessible to scholars and educators. We present an application of modern 3D computer graphics in the field of reconstructing ancient scientific instruments. The first-four-species calculator of Wilhelm Schickard is made accessible to the public in the World Wide Web using Java 3D.  相似文献   

14.
This paper describes how some innovative methodologies have been designed and employed to support the restoration of the Madonna of Pietranico, a terracotta statue severely damaged in the 2009 earthquake. The statue, fragmented in many pieces, has undergone a complex restoration performed by a multidisciplinary working group. The contribution of digital technologies was planned from the very beginning, since the complexity of this restoration originated the design of innovative procedures for managing the reassembly and restoration process. The Madonna test bed was therefore an example of how technology innovation could be pushed by clear application needs. A first important contribution was the study of the recombination hypothesis of the fragments. This initial phase was performed on digitized 3D models of the statue fragments, with the aim of reducing fragments manipulation, preventing further damages and increasing the capabilities to rehearse and evaluate different reassembly options. The accuracy of the 3D scanned models and the new recombination procedure introduced in this paper allowed to manage this phase in the digital domain with successful results. The digital 3D models were also used to design and produce an innovative supporting structure, constructed with a rapid prototyping device. Another important contribution concerned the study and virtual restoration of the polychrome decoration of the statue; our aim was to reproduce and restore in the virtual 3D domain the very complex original polychrome decoration, on the base of the remaining traces. Consequently, new virtual painting functionalities have been designed on the MeshLab platform (an open-source tool for 3D models visualization and manipulation) for reproducing pictorial decorations over digital 3D models and have been assessed on this specific test bed. This allowed us also to investigate the complexity of the virtual repainting process and to identify further technology enhancements. Finally, computer graphics technologies have been also used to produce a video that tells the story of the restoration.  相似文献   

15.
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16.
The possibility of giving a continuing value to an abandoned historic mine is not only of academic interest but can be a crucial economic and heritage issue for regions with long mining traditions but which are now severely affected by mine closures. This article suggests a different perspective on the rationale for studying, preserving and developing our mining heritage as an educational facility. To illustrate the case, the ancient iron mine of Llumeres, in the Asturias region, in North Spain, is presented as an example. A key point of our thesis is that a closed mine is not a ‘dead entity’ but simply in transition to another useful state and that after the closure, another organism arises, with very different appearance and vital signs. We suggest that this new organism be recognised for its high patrimonial value and that this heritage value be preserved. Accepting this point of view would mean an increase in efforts to identify and appropriately manage these vital signs. We propose that the particular mining-related aspects (which are usually viewed as negative, such as subsidence or groundwater modification), be considered as part of the heritage of the mining activity, considered in the widest sense. To facilitate understanding, these are discussed in comparison to those for a prehistoric cave, for which there is a broader experience and solid knowledge and recognition of heritage value. We have also analyzed the importance of recognising the geometric and functional relationships between the underground workings and the superficial signatures, in defining an extended patrimonial entity, which has been recently presented to the cultural and political authorities. For the case of the iron mine of Llumeres, we explain the methodology required to analyze and classify the documents in order to investigate and reconstruct the 3D geometric structure of the mine and how this can be integrated into a Geographical Information System (GIS) to improve management and editing of the information. Additionally, the historic mining technological methods employed in the underground workings of Llumeres have been studied and all the information integrated into a 3D visualization package and made available as a free 3D video sample of the subsurface information. In summary, this work represents a major step forward in improving our knowledge of the ancient iron mine of Llumeres and, as a consequence, it has been possible, for the first time, to consider the underground mining heritage in the framework of the better known (but as yet unrecognised) overground heritage. This new patrimonial entity offers enhanced possibilities for acceptance and recognition in a societal context and to aid that acceptance, we propose a radical conceptual change of perspective, pointing out new elements requiring research.  相似文献   

17.
We present a novel 3D reassembly method for fragmented, thin objects with unknown geometry. Unlike past methods, we do not make any restrictive assumptions about the overall shape of the object, or its painted texture. Our key observation is that regardless of the object's shape, matching fragments will have similar geometry and photometry along and across their adjoining regions. We begin by encoding the scale variability of each fragment's boundary contour in a multichannel, 2D image representation. Using this multichannel boundary contour representation, we identify matching sub-contours via 2D partial image registration. We then align the fragments by minimizing the distance between their adjoining regions while simultaneously ensuring geometric continuity across them. The configuration of the fragments as they are incrementally matched and aligned form a graph structure that we use to improve subsequent matches. By detecting cycles in this graph, we identify subsets of fragments with interdependent alignments. We then minimize the error within the subsets to achieve a globally optimal alignment. We leverage user feedback to cull the otherwise exponential search space; after each new match is found and aligned, it is presented to a user for confirmation or rejection. Using ceramic pottery as the driving example, we demonstrate the accuracy and efficiency of our method on six real-world datasets.  相似文献   

18.
The survey of materials constituting the buildings of the ancient city centre of Naples and of their decay typologies was carried out. Reports were entered in a database which enabled us to draw two thematic maps in a digital format: one of materials and lithotypes, and one showing weathering. On this basis, quantitative evaluations of the lithotypes were carried out. The research pointed out that the use of different lithotypes was mainly as a result of their availability and/or ease of exploitation. Furthermore, the importance of the preservation of the quarrying sites was stressed, both for their historical and cultural interest and, above all, for possible forthcoming provisioning finalized to restorations. The analysis of the results, made on a geo-mineralogical basis, as well as the thematic maps, gives a basic tool which will be very useful to those professionals involved in preservation of cultural heritage.  相似文献   

19.
Different techniques and tools currently exist to generate three-dimensional models of small elements, buildings and cities. Apart from being easier to interpret than two-dimensional drawings, these models facilitate data necessary for reconstruction projects, preservation or rehabilitation of the architectural or archaeological heritage. Traditional surveying only enables us to obtain discrete information of the characteristic lines that define each surface, edge, slope change etc. whereas work with massive capture techniques allows us to obtain continuous points of the surfaces. Photogrammetry or laser scanning combined with conventional photography provides information of the building in addition to its geometry. We carried out a review of the different techniques showing the advantages and disadvantages of each technique as well as the information that can be obtained by applying these techniques to the survey of the great Gate of Antioch in the town of Aleppo, declared a World Heritage Site by UNESCO in 1986, in Syria.  相似文献   

20.
In the last few years the improved performances of graphics hardware and the growing availability of broadband internet connections have eventually led to effectively adding a third dimension to web interfaces, achieving what is commonly referred to as Web3D. Nevertheless, these technologies are not yet widespread, especially in the cultural sector, for at least two factors: technological limitations, mostly in the lack of coherent and effective metaphors to visualize and interact with digital cultural assets using the third-dimension as an added value rather than as a stylish gadget, and communication issues, as, despite the principles stated in the London Charter aimed at ensuring technical and intellectual rigor for the digital visualization of cultural heritage, a proper way to deal with relevant and sustainable 3D information is not yet completely established. For this reason this paper focuses on identifying and analyzing the aspects that may contribute to a more efficient use of Web3D technologies to access cultural content, in order to set up a set of development standards aiming to encourage web-based learning and guaranteeing systems accessible and usable by the widest possible audience.  相似文献   

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