Anna Maria Manferdini

A Review of Reality-Based 3D Model Generation, Segmentation and Web-Based Visualization Methods

The tremendous improvements in data capturing technologies and in the related processing methodologies are opening more and more possibilities in different fields of applications. In particular the Cultural Heritage field is taking great advantages from the latest reality-based 3D modelling developments. One of the most significant consequences of the introduction of digital 3D modelling in the heritage field is the great opportunity of using 3D models as highly effective and intuitive means of communication or as interfaces to share and visualize information collected e.g. in databases. Unstructured 3D data recorded with photogrammetry or laser scanning techniques are generally converted in polygonal textured 3D models, subdivided and organized using automated and manual methods and finally visualized using web-based tools in order to allow remote access and data retrieval to a wider range of users, with evident advantages in enlarging knowledge and education. The paper presents the state-of-the-art in 3...

Reality-based 3D modeling, segmentation and web-based visualization

One of the most significant consequences of the introduction of digital 3D modeling in the Cultural Heritage field is the possibility to use 3D models as highly effective and intuitive means of communication as well as interface to share and visualize information collected in databases. Due to the usual complexity of architectural and archaeological artifacts or sites, their digital models need be subdivided in sub-components and organized following semantic definitions in order to facilitate data retrieval. This paper outlines a methodology to semantically segment complex reality-based 3D models, annotate information and share the results within online open-source tools. The segmentation stage to subdivide and organize 3D models is based on both automated and manual methods, giving priority to automated procedures that can ease and speed these steps but not neglecting the user intervention to achieve accurate results. The segmented 3D models are then visualized in web-based systems to allow data access to a wider range of users and enlarge knowledge. The methodology is presented and tested on large and complex reality-based 3D models of architectural and archaeological heritage structures.

Multi-scalar 3D digitization of Cultural Heritage using a low-cost integrated approach

In the architectural survey field, one of the main aspects to consider during a 3D digitization is the multi-scalar geometrical complexity of the artifact to acquire, besides other fundamental factors connected with the different aims of communication. Since the widespread of range-sensors has provided extremely versatile instruments able to easily acquire huge amount of data that can be processed for different uses and users and changing communication aims, the possibility to survey and restore high-quality 3D multi-resolution models has become an urgent need. Despite these developments, these technologies are still very expensive, need expertise and present persistent bottlenecks both in the reverse modeling process and in time consuming. In order to overcome these critical aspects and taking advantage of recent improvements of automated image-based technologies based on the Structure from Motion approach, this contribution presents some first results of investigations on the reliability of these low-cost technologies for the 3D digitization of Cultural Heritage. One of the main aims of these investigations rely on developing a procedure that could ease the work of surveyors called to represent artifacts at an architectural scale using fast and low-cost technologies. 3D models derived using the selected low-cost image-based technologies were compared among each other and with a 3D laser scanner gold standard acquisition. These investigations led to qualitative and quantitative evaluations and to considerations on times and skills required by all tested technologies. Strengths and weaknesses are highlighted, suggesting the best solution with respect to the optimization of all considered aspects. Finally, integration of different technologies are presented, as it represents the best solution in multi-scalar contexts.

A methodology for the promotion of cultural heritage sites through the use of low-cost technologies and procedures

In the Cultural Heritage field a large variety of sites and artifacts could benefit from their free access and promotion through the web. But despite the possibilities offered by digital technologies [Manferdini and Remondino 2012], the high costs that are generally connected with their use, the lack of standard procedures and the need to train expert operators often limit the widespread digitization of Cultural Heritage sites and artifacts. As a consequence, during the last three decades, researches in the field of image-based technologies, such as, in particular, the Structure from Motion one [Ullman 1979], as well as the development of open-source algorithms and software aimed at helping the processing, management and visualization of 3d data through the web represent remarkable attempts to extend the use of digital technologies and procedures in this field.

Reconstructing the lost reality archaeological analysis and Transmedial Technologies for a perspective of Virtual Reality in the Etruscan city of Kainua

This paper presents the very first results of a three-year research program concerning the digital reconstruction of an entire Etruscan town, based on a philological analysis of archaeological data. The archaeological site and the adjacent museum will be then provided with suitable systems of perception and discovery of the archaeological reality, fully reconstructed due to innovative Transmedial Technologies based on Virtual Reality and, since this work is still in progress, studied through future digital models based on historic BIM process.

The use of low-cost technologies for the promotion of Cultural Heritage sites: The case study of Veleia

In the Cultural Heritage field, thanks to the recent development of digital technologies, a large variety of sites and artifacts could benefit from their free access and promotion through the web. But despite these achievements, the high costs that are generally connected with their use often limit their widespread. As a consequence, during the last two decades, scientific research is developing new tools and methodologies aimed at overcoming this problem. In particular, for example, researches in the field of image-based technologies and the development of open-source algorithms and software aimed at helping the processing, management and visualization of 3d data through the web represent remarkable attempts to extend the use of digital technologies in the Cultural Heritage field. This contribution shows the main steps of a project aimed at testing low-cost technologies within the multi-scalar digitization process of sites and artifacts. Thus these technologies still cannot provide analogous results in terms of definition and accuracy that it is possible to achieve using more expensive technologies (e.g. range-based technologies), they can supply low-resolution reality-based 3d models and effective representations that can be easily accessed through the web, with evident benefits in cultural contents sharing and promotion. Within a multi-scalar approach, the building of these kinds of models represents the first step of a process that, starting from low-resolution acquisitions, can improve the detail and definition of 3d digital models of artifacts by gradually adopting different methodologies and technologies. As a consequence, this approach can provide evident benefits on the achievement of different communication purposes, ranging from simple visualizations for popular aims to accurate and faithful digital replicas that can be fruited by different and changing users. Moreover, the adoption of this approach is particularly important within education processes aimed at training expert operators able to speed and therefore to further reduce costs connected with the digitization of Cultural Heritage.

Documenting Lost Heritage: The Experience of the Survey of Architectures Damaged by the Earthquake in the Emilia Area, Italy

Two years ago, the earthquake that devastated a wide architectural heritage in the Emilia area, in Northern Italy, gave rise to a series of surveys and investigations aimed at both documenting a lost or seriously compromised heritage and at recording information that can be used by different operators (i.e. fire departments, civil protection, engineers, architects, urban planners) and for different uses in different times, concerning the development of safety, recovery, restoration or demolition programs. The aim of this contribution is to show how digital technologies and in particular non-contact 3D survey methodologies can be used as an indispensable practice in order to rapidly and safely produce graphic documentation about an architectural heritage that has been destroyed or severely damaged by a natural disaster. The presented case studies belong to a repertoire that ranges from single buildings to wider complexes that were selected for their historical and cultural importance and for the urgency of the development of intervention plans.