Search results for "Image based"

Architectural Perspectives in the Cathedral of Palermo: Image-Based Modelling for Cultural Heritage Understanding and Enhancement

2015

Palermo off ers a repertoire of both artistic and architectural solid perspective of great beauty and in large quantity. This paper addresses the problem of the 3D survey of these works and their related study through the use of image-based modelling (IBM) techniques. We propose, as case studies, the use of IBM techniques inside the Cathedral of Palermo. Indeed, the church houses a huge and rich sculptural repertoire, dating back to 16th century, which constitutes a valid field of IBM techniques application. The aim of this study is to demonstrate the e ffectiveness and potentiality of these techniques for geometric analysis of sculptured works. Indeed, usually the survey of these artworks …

Image-based 3D reconstruction using traditional and UAV datasets for analysis of road pavement distress

2018

Abstract On local and urban networks, the enduring issue of scarce resources for Maintenance, Rehabilitation, and Reconstruction strategies (MR&R) has led, in many cases, to using unadjusted or poor techniques for road pavement distress detection and analysis, yielding ineffective or even counterproductive results. Therefore, it is necessary to have tools that can carry out quick, reliable and low-cost assessment surveys. This paper aims at validating the use of innovative and low-cost technologies for road pavement analysis, assessing their potentialities for improving the automation and reliability of distress detection. A Structure from Motion (SfM) technique is analyzed at different alt…

Using dense stereo matching techniques in survey

2013

In recent years there has been an enormous increase in the dissemination of modelling techniques known as dense stereo matching (DSM) or image-based modelling (IBM) using free, low cost, open source software, especially applications involving the survey of cultural heritage (architecture, archaeology, and town planning). The algorithms used by these software programmes process photographic datasets and provide a 3D model of the scene in question. During complex survey and 3D restitution procedures, these techniques save time (processing) and money: these advantages Can he useful to any professional. This is why it is important to identify the real potential and limits of these software prog…

Hand Held 3D Scanning for Cultural Heritage: Experimenting Low Cost Structure Sensor Scan

2017

In the last years 3D scanning has become an important resource in many fields, in particular it has played a key role in study and preservation of Cultural Heritage. Moreover today, thanks to the miniaturization of electronic components, it has been possible produce a new category of 3D scanners, also known as handheld scanners. Handheld scanners combine a relatively low cost with the advantage of the portability. The aim of this chapter is two-fold: first, a survey about the most recent 3D handheld scanners is presented. As second, a study about the possibility to employ the handheld scanners in the field of Cultural Heritage is conducted. In this investigation, a doorway of the Benedictin…

Low Cost Handheld 3D Scanning for Architectural Elements Acquisition

2016

3D scanning has gone a long way since its first appearance in cultural heritage digitization and modeling. In the recent years some new low cost, fast, accurate emerging technologies are flooding the market. Envisioning the massive use of these cheap and easy to use devices in the next years, it is crucial to explore the possible fields of application and to test their effectiveness in terms of easiness of 3D data collection, processing, mesh resolution and metric accuracy against the size and features of the objects. In this study we focus the attention on one emerging technology, the Structure Sensor device, in order to verify a 3D pipeline acquisition on an architectural element and its …

THE DIAGNOSIS OF ROAD SURFACE DISTRESSES THROUGH IMAGE-BASED MODELING TECHNIQUES. EXPERIMENTAL SURVEY ON LABORATORY-RUTTED SAMPLES

2015

In the past few years, there has been a drastic increase in the use of image-based modeling (IBM) techniques to create high quality, reality-based 3D models. The low costs of these techniques, as well as their attractive visual quality, have led many researchers and professionals to invest their energy and resources in several tests. IBM is rarely used in the field of road surface distresses as diagnosis is usually performed using other techniques and devices. Road safety statistics reveal that about a half of the total number of accidents occur mainly due to the deterioration of the pavement. The goal of effective road network management is often incompatible with economic resources design…

Integrated prototyping and rendering system for the display of ceramic finds

2017

The project, carried out in collaboration between the Department of Architecture of Palermo and the Archaeological Museum Antonino Salinas of Palermo, proposes a system of integration and reconstruction of ceramic artefacts, using modeling, 3D printing and rendering processes for an integrated museum exhibition system, which the viewers can observe the fragment nearing the re-reconstructed fragment that reconstructs the original morphology and an interactive digital model in which the viewers can also observe the metric aspect and, where present, the decorative apparatus.

F55. An Image-Based Meta-Analysis of Successful and Failed Stopping in Attention Deficit/Hyperactivity Disorder Using Statistical Parametric Maps

2019

Image-based MRI Gradient Estimation

2017

In order to reduce geometric distortion phenomena in MR images, every MRI system main magnet undergoes a shimming process. Since this process aims at optimizing magnetic field homogeneity within a so-called uniformity sphere, image quality outside this sphere is neglected. Since the fields vary smoothly in space, MR signal-to-noise ratio is still non-zero just outside the uniformity region, but correction of MR image distortion fails due to lack of magnetic field knowledge outside it. We propose a novel algorithm for measuring all the fields involved in the generation of images. Our proposal is based on exploitation of the distortion which can be observed in images of a known phantom. The p…

Velocity and turbulence measurements: uncertainty in the application of the Image-based technique

2018

This work focuses on the application of image-based technique to estimate velocity and turbulent flow characteristics. In particular, in the present work digital imaging technique is used for performing surface velocity measurements of hyper-concentrated flows. The analysis is conducted with the aid of data collected in a scale laboratory flume constructed at the Hydraulic laboratory of the Department of Civil, Environmental, Aerospatial and of Materials Engineering (DICAM) – University of Palermo (Italy). In the present paper a brief summary of results obtained in previous works on the flow velocity estimation error and uncertainty related to the acquisition procedure is reported.