Search results for "computer graphic"
showing 10 items of 530 documents
Reconstruction of hyperspectral cutaneous data from an artificial neural network-based multispectral imaging system.
2011
International audience; The development of an integrated MultiSpectral Imaging (MSI) system yielding hyperspectral cubes by means of artificial neural networks is described. The MSI system is based on a CCD camera, a rotating wheel bearing a set of seven interference filters, a light source and a computer. The resulting device has been elaborated for in vivo imaging of skin lesions. It provides multispectral images and is coupled with a software reconstructing hyperspectral cubes from multispectral images. Reconstruction is performed by a neural network-based algorithm using heteroassociative memories. The resulting hyperspectral cube provides skin optical reflectance spectral data combined…
Noise estimation from digital step-model signal
2013
International audience; This paper addresses the noise estimation in the digital domain and proposes a noise estimator based on the step signal model. It is efficient for any distribution of noise because it does not rely only on the smallest amplitudes in the signal or image. The proposed approach uses polarized/directional derivatives and a nonlinear combination of these derivatives to estimate the noise distribution (e.g., Gaussian, Poisson, speckle, etc.). The moments of this measured distribution can be computed and are also calculated theoretically on the basis of noise distribution models. The 1D performances are detailed, and as our work is mostly dedicated to image processing, a 2D…
3D part inspection path planning of a laser scanner with control on the uncertainty
2011
International audience; This article concerns the measurement process of mechanical parts using laser scanners. From the point of view of industrial applications, the objective is to guarantee the measurement accuracy during the scanning with regard to the geometrical product specifications. The proposed method can be summarized as follow: the first step consists of analyzing the interval of tolerance for the different specifications and to attribute to every geometrical entity a maximal uncertainty of measurement. This uncertainty depends on the angle of incidence between the laser plane and the scanned surface. In the second step, an approach based on the concept of visibility is used fro…
LDR Image to HDR Image Mapping with Overexposure Preprocessing
2013
International audience; Due to the growing popularity of High Dynamic Range (HDR) images and HDR displays, a large amount of existing Low Dynamic Range (LDR) images are required to be converted to HDR format to benefit HDR advantages, which give rise to some LDR to HDR algorithms. Most of these algorithms especially tackle overexposed areas during expanding, which is the potential to make the image quality worse than that before processing and introduces artifacts. To dispel these problems, we . present a new,LDR to HDR approach, unlike the existing techniques, it focuses on avoiding sophisticated treatment to overexposed areas in dynamic range expansion step. Based on a separating principl…
Modélisation géométrique de formes fractales pour la CAO
2020
International audience
Close-Range Photogrammetric Tools for Epigraphic Surveys
2016
In this article, we present a method to carry out a computerized epigraphic survey of historic stones and their engraved epigraphy. In fact, the preservation of archaeological objects has always been an issue of concern for the research community. On the one hand, the fragility of the objects limits their study. On the other hand, such objects are housed in museums, libraries, and institutions worldwide, locations that significantly limit their accessibility. Different survey methods have been carried out in these attempts to overcome the aforementioned limitations. Among them, the MicMac open source software was used in this work to survey and process the dense correlation of the hieroglyp…
Contextualization of archaeological information using augmented photospheres, viewed with head-mounted displays.
2019
Photospheres, or 360°
Extension des méthodes de géométrie algorithmique aux structures fractales
2013
Defining shapes by iteration allows us to generate new structures with specific properties (roughness,lacunarity), which cannot be achieved with classic modelling.For developing an iterative modeller to design fractals described by a BCIFS, we developed a set oftools and algorithms that permits one to evaluate, to characterize and to analyse different geometricproperties (localisation, convex hull, volume, fractal dimension) of fractals. We identified properties ofstandard CAD operations (intersection, union, offset, . . . ) allowing us to approximate them for fractalsand also to optimize these approximation algorithms.In some cases, it is possible to construct a CIFS with generalised HUTCH…
Una política juvenil para promover el desarrollo local: un estudio de caso
2019
El artículo presenta un estudio de caso de una política juvenil realizada en la última década en una región del Sur de Italia. Su interés reside en la versatilidad, el enfoque multidimensional y en el hecho de haber actuado como un óptimo instrumento de desarrollo local. El estudio de caso se ha realizado a través del análisis documental de las evaluaciones ex -ante, durante y ex – post que se hicieron para valorar el impacto de la política. La reflexión que el caso propone se enfoca en cómo se puede promover eficazmente el desarrollo local a través de políticas más trasversales.
Multiverse Ethnography: A Qualitative Method for Gaming and Technology Use Research
2021
This article introduces multiverse ethnography as a systematic team-based qualitative method for studying the mechanical, structural and experiential properties of video games and other technological artefacts. Instead of applying the ethnographic method to produce a single in-depth account, multiverse ethnography includes multiple researchers carrying out coordinated synergetic ethnographic work on the same research object, thus producing a multiverse of interpretations and perspectives. To test the method, 41 scholars carried out a multiverse ethnography on two video games, Cyberpunk 2077 and Among Us. Explorative thematic findings regarding both titles are reported and methodological imp…