Search results for " image processing."
showing 10 items of 2265 documents
Shape optimization for Stokes problem with threshold slip boundary conditions
2017
This paper deals with shape optimization of systems governed by the Stokes flow with threshold slip boundary conditions. The stability of solutions to the state problem with respect to a class of domains is studied. For computational purposes the slip term and impermeability condition are handled by a regularization. To get a finite dimensional optimization problem, the optimized part of the boundary is described by B´ezier polynomials. Numerical examples illustrate the computational efficiency. peerReviewed
Analysis of the performance of the TES algorithm over urban areas
2014
International audience; The temperature and emissivity separation (TES) algorithm is used to retrieve the land surface emissivity (LSE) and land surface temperature (LST) values from multispectral thermal infrared sensors. In this paper, we analyze the performance of this methodology over urban areas, which are characterized by a large number of different surface materials, a variability in the lowest layer of the atmospheric profiles, and a 3-D structure. These specificities induce errors in the LSE and LST retrieval, which should be quantified. With this aim, the efficiency of the TES algorithm over urban materials, the atmospheric correction, and the impact of the 3-D architecture of urb…
Fast prototyping of parallel image processing applications using functional skeletons
1999
We present SKiPPER, a software dedicated to the fast prototyping of vision algorithms on MIMD/DM platforms. This software is based upon the concept of algorithmic skeletons, i.e. higher order program constructs encapsulating recurring forms of parallel computations and hiding their low-level implementation details. Examples of such skeletons in low- to mid-level image processing include such as geometric decompositions, data or task farming. Each skeleton is given an architecture-independant functional (but executable) specification, a portable implementation as a process template and an analytic performance model. The source program is a purely functional specification of the algorithm in …
FROM SURVEY TO MODEL, AND RETURN. THE CASE OF THE PARMA BAPTISTERY
2019
Abstract. Although this is not always the common practice, the survey should be an essential preliminary stage to any operation of restoration, enhancement and promotion of cultural heritage. Today, various surveying techniques make it possible to collect large amounts of data quickly and to provide a complete three-dimensional representation of extremely complex artefacts. In fact, 3D models allow a much richer description than traditional 2D representations. However, these survey techniques (laser scanner and photogrammetry above all) necessarily imply that the data that must be elaborated during the processing phase increase dramatically. It is therefore essential to identify methods and…
SCAN-TO-BIM FOR THE MANAGEMENT OF HERITAGE BUILDINGS: THE CASE STUDY OF THE CASTLE OF MAREDOLCE (PALERMO, ITALY)
2020
Abstract. Conservation and preservation of heritage buildings require the knowledge and sharing of a great deal of data and information about buildings. Such information comes from the different disciplines involved in the restoration and maintenance processes. The integration and use of all this information in a single working environment is a key factor for the success of historical building conservation and management projects. Heritage (or Historic) Building Information Modelling (HBIM) is nowadays the most appropriate tool to collect and manage all data related to Architectural Heritage. The HBIM process requires an in-depth knowledge of the historical building that can be achieved usi…
A GAMING APPROACH FOR CULTURAL HERITAGE KNOWLEDGE AND DISSEMINATION
2019
Abstract. In these last years, video games have become one of the most popular entertainment for children/teenagers/adults thanks to their appealing and seductive features and, in this context, the Serious Games (SG) have become an important research field. The most popular SGs in Cultural Heritage (CH) used the historical building like scenario where the game is playing. In this paper we show the procedure to achieve a CH video game where the Cultural Heritage is the main actor and not the scenario of the game. Furthermore, the game is not a SG but an Action-Adventure Game (AAG) or Survival Game (SuG), in a largest heading it can be classified as Entertainment Games (EGs). The novelty of t…
Minimal learning machine in anomaly detection from hyperspectral images
2020
Abstract. Anomaly detection from hyperspectral data needs computationally efficient methods to process the data when the data gathering platform is a drone or a cube satellite. In this study, we introduce a minimal learning machine for hyperspectral anomaly detection. Minimal learning machine is a novel distance-based classification algorithm, which is now modified to detect anomalies. Besides being computationally efficient, minimal learning machine is also easy to implement. Based on the results, we show that minimal learning machine is efficient in detecting global anomalies from the hyperspectral data with low false alarm rate.
INTEGRATED SURVEY FOR ARCHITECTURAL RESTORATION: A METHODOLOGICAL COMPARISON OF TWO CASE STUDIES
2016
Abstract. A preliminary survey campaign is essential in projects of restoration, urban renewal, rebuilding or promotion of architectural heritage. Today several survey techniques allow full 3D object restitution and modelling that provides a richer description than simple 2D representations. However, the amount of data to collect increases dramatically and a trade-off between efficiency and productivity from one side and assuring accuracy and completeness of the results on the other must be found. Depending on the extent and the complexity of the task, a single technique or a combination of several ones might be employed. Especially when documentation at different scales and with different …
MAIN FEATURES OF A 3D GIS FOR A MONUMENTAL COMPLEX WITH AN HISTORICAL-CULTURAL RELEVANCE
2018
Abstract. The last achievements of technologies in geomatics especially in survey and restitution of 3D models (UAV/drones and laser scanner technologies) generated new procedures and higher standards of quality in representation of archaeological sites. Together with Geomatics, the recent development of Information and Communication Technologies (ICT) strongly contribute to document and the Cultural Heritage (CH). The representation and documentation of CH using these new technologies has became necessary in order to satisfy different needs: – for restorers in order to acquire a deep knowledge of the cultural good and to define possible strategies of restoration; – for the conservation of …
THE MAIN PORTAL OF THE CATHEDRAL OF MONREALE: FIRST GEOMETRIC ANALYSIS AND INTERPRETIVE ASSESSMENT OF ARCHITECTURAL FEATURES
2017
Abstract. Nowadays, 3D documentation of architectural assets is becoming a demanding task for the valorisation of Cultural Heritage especially after a restoration project. The 3D documentation can be used for detailed analysis of specific elements, for monitoring the state of conservation and for valorisation actions. The paper describes the results of the 3D close-range photogrammetry survey of the main portal of the Cathedral of Monreale (Palermo, Italy). The Cathedral is one the most important monumental complexes in Sicily that, for its high historical and artistic importance has been inscribed on UNESCO’s World Heritage List since 2015. The main portal of the Cathedral has been recentl…