PCA-based method for managing and analyzing single-spot analysis referenced to spectral imaging for artworks diagnostics

Artworks diagnostics is based on the joint use of several nondestructive techniques to acquire complementary information on the materials. A common practice in the field is to perform the analyses with single-spot analytical techniques, e.g. spectroscopy-based, after a preliminary screening of the artwork with full-field imaging-based techniques. We present a method and its practical implementation for fusing and analyzing data collected using analytical systems that acquire single spot measurements mapped to spectral imaging stacks. The fused dataset of single-spot and imaging observations is analyzed using principal component analysis (PCA). The effectiveness of the method for artworks diagnostics is shown on spectroscopy and imaging datasets of an ancient canvas painting. The results of the PCA analysis on the final fused dataset are compared against the PCA analysis performed on the original datasets from single-spot and imaging measurements taken separately. We propose two practical implementations of the procedure, one based on using graphical user interface (GUI) and open-source GIS software (QGIS), the other one based on an open-source Python module, named SPOLVERRO, specifically developed for this project and released on a public repository. The method allows conservation scientists to analize effectively the heterogeneous datasets acquired in a diagnostic campaign. single-spot spectroscopy data are referenced on imaging data.the sampling area of each spectroscopy spot is used for extracting and averaging the respective imaging data values.the final matrix is analyzed using PCA for extracting further information

Surface Metrology Based on Scanning Conoscopic Holography for In Situ and In-Process Monitoring of Microtexture in Paintings

In the field of engineering, surface metrology is a valuable tool codified by international standards that enables the quantitative study of small-scale surface features. However, it is not recognized as a resource in the field of cultural heritage. Motivated by this fact, in this work, we demonstrate the use and the usefulness of surface metrology based on scanning conoscopic holography for monitoring treatments on the Venetian masterpiece by Tintoretto St. Martial in Glory with the Saints Peter and Paul. We carried out in situ and in-process monitoring of the painting microtexture during an experimental, innovative laser–chemical treatment, and we performed a statistical analysis based on ISO areal field parameters. A wide and in-band roughness analysis through the complementary use of amplitude, spatial, and hybrid parameters confirmed the noninvasive nature of the whole treatment on the painting surface topography, giving us the chance to review and critically discuss the use of these parameters in a real case in heritage science

A Novel Framework for Highlight Reflectance Transformation Imaging

We propose a novel pipeline and related software tools for processing the multi-light image collections (MLICs) acquired in different application contexts to obtain shape and appearance information of captured surfaces, as well as to derive compact relightable representations of them. Our pipeline extends the popular Highlight Reflectance Transformation Imaging (H-RTI) framework, which is widely used in the Cultural Heritage domain. We support, in particular, perspective camera modeling, per-pixel interpolated light direction estimation, as well as light normalization correcting vignetting and uneven non-directional illumination. Furthermore, we propose two novel easy-to-use software tools to simplify all processing steps. The tools, in addition to support easy processing and encoding of pixel data, implement a variety of visualizations, as well as multiple reflectance-model-fitting options. Experimental tests on synthetic and real-world MLICs demonstrate the usefulness of the novel algorithmic framework and the potential benefits of the proposed tools for end-user applications.Terms: "European Union (EU)" & "Horizon 2020" / Action: H2020-EU.3.6.3. - Reflective societies - cultural heritage and European identity / Acronym: Scan4Reco / Grant number: 665091DSURF project (PRIN 2015) funded by the Italian Ministry of University and ResearchSardinian Regional Authorities under projects VIGEC and Vis&VideoLa

Multiscale roughness analysis by microprofilometry based on conoscopic holography: a new tool for treatment monitoring in highly reflective metal artworks

The analysis of surface roughness in highly reflective metal artworks is challenging and requires contactless devices capable to measure regions with high micrometer accuracy in both depth and lateral directions. We demonstrate optical profilometry based on scanning conoscopic holography for micrometer measurement of silver samples treated with different hand-made cleaning processes. The technique is shown effective in acquiring shiny and smooth metal samples providing high-resolution and highaccurate dataset (0.1µm depth and 5µm lateral resolution) that is a reliable representation of the microsurface structure. From a statistical point of view, the cleaning treatments have the same nature of the low-abrasion, but the underlying mechanical processes are different. This fact suggested a more in-depth study of both the amplitude and the hybrid areal roughness parameters. It is proposed a workflow for a dual integrated multiscale roughness analysis for surface characterization: a scale inspection to detect possible texture non-homogeneity, and a signals separation to outline the most significant texture components. The scale-limited components allowed to discriminate the different surface processes. The results on silver samples demonstrate the potential of multiscale roughness analysis by conoscopic holography as a new tool for treatment monitoring in metal artworks

Feasibility and performance analysis in 3D printing of artworks using laser scanning microprofilometry

We investigated optical scanning microprofilometry and conoscopic holography sensors as nondestructive testing and evaluation tools in archeology for obtaining an accurate 3D printed reproduction of the data. The modular microprofilometer prototype allows a versatile acquisition of different materials and shapes producing a high-quality dataset that enables surface modelling at micrometric scales from which a "scientific" replica can be obtained through 3D printing technologies. As exemplar case study, an archeological amphora was acquired and 3D printed. In order to test the feasibility and the performance of the whole process chain from the acquisition to the reproduction, we propose a statistical multiscale analysis of the surface signal of object and replica based on metrological parameters. This approach allows to demonstrate that the accuracy of the 3D printing process preserves the range of spatial wavelengths that characterizes the surface features of interest within the technology capabilities. This work extends the usefulness of the replicas from museum exposition to scientific applications

Focus-stacking system for 3D acquisition of sculptures and archaeological manufacts

In this paper we present the basic features of the Shape from Focus techniques and discuss the potentiality of its application in the 3D imaging of small sculptures and archaeological manufacts. A scanning system for optimizing the image stack acquisition in laboratory was assembled, while 3D reconstruction was done in ImageJ

Edificio para la enseñanza: fortalecimiento del espacio público

Ubicación: (Zona sur del Gran Buenos Aires) 23km de Capital Federal, 35km de La Plata. El sitio a intervenir forma parte de la Región Metropolitana de Buenos Aires caracterizándose como punto estratégico de intersección urbana regional, posicionándose como elemento articulador que conecta y relaciona distintos puntos y actividades. Es una sector donde los flujos de circulación son constantes y esto lleva a la necesidad del diseño del vacío urbano, del cual hay una gran carencia y es fundamental para el bien común. Los años han reflejado un crecimiento urbano desmedido y no planificado en estos sectores, desbordando los límites naturales y avanzando sobre estas zonas, generando situaciones complejas, de baja calidad urbana, de difícil acceso a los servicios, una tendencia al empeoramiento de las condiciones socio- habitacionales al aumentarse la distancia al centro y a ejes viales principales, resultando territorios despojados de urbanidad. Se requiere de intervenciones en distintas escalas para solucionar los diferentes factores, considerando que Florencio Varela pertenece a una región, las intervenciones deben pensarse de manera integral con respecto a los demás componentes de la misma y considerando su impacto de manera regional. El campus universitario de la UNAJ, es uno de los pocos Espacios Públicos que se encuentra en el sector, por lo tanto la intervención en el mismo busca comprender lógicas de identidad y comportamiento social, buscando la generación de proyectos que contribuyan al bienestar general y al acceso a derechos urbanosFacultad de Arquitectura y Urbanism

Digital cultural heritage imaging via osmosis filtering

In Cultural Heritage (CH) imaging, data acquired within different spectral regions are often used to inspect surface and sub-surface features. Due to the experimental setup, these images may suffer from intensity inhomogeneities, which may prevent conservators from distinguishing the physical properties of the object under restoration. Furthermore, in multi-modal imaging, the transfer of information between one modality to another is often used to integrate image contents. In this paper, we apply the image osmosis model proposed in [4, 10, 12] to solve correct these problems arising when diagnostic CH imaging techniques based on reflectance, emission and fluorescence mode in the optical and thermal range are used. For an efficient computation, we use stable operator splitting techniques to solve the discretised model. We test our methods on real artwork datasets: the thermal measurements of the mural painting “Monocromo” by Leonardo Da Vinci, the UV-VIS-IR imaging of an ancient Russian icon and the Archimedes Palimpsest dataset

Sensori on-line per un approccio termodinamico ai fenomeni termici nella formazione iniziale degli insegnanti,

Sensori on-line per un approccio termodinamico ai fenomeni termici nella formazione iniziale degli insegnant