Search results for "Graphics"

Fast Computation by Subdivision of Multidimensional Splines and Their Applications

2016

We present theory and algorithms for fast explicit computations of uni- and multi-dimensional periodic splines of arbitrary order at triadic rational points and of splines of even order at diadic rational points. The algorithms use the forward and the inverse Fast Fourier transform (FFT). The implementation is as fast as FFT computation. The algorithms are based on binary and ternary subdivision of splines. Interpolating and smoothing splines are used for a sample rate convertor such as resolution upsampling of discrete-time signals and digital images and restoration of decimated images that were contaminated by noise. The performance of the rate conversion based spline is compared with the…

ON SOME GENERALIZATION OF SMOOTHING PROBLEMS

2015

The paper deals with the generalized smoothing problem in abstract Hilbert spaces. This generalized problem involves particular cases such as the interpolating problem, the smoothing problem with weights, the smoothing problem with obstacles, the problem on splines in convex sets and others. The theorem on the existence and characterization of a solution of the generalized problem is proved. It is shown how the theorem gives already known theorems in special cases as well as some new results.

An Efficient Implementation of Parallel Parametric HRTF Models for Binaural Sound Synthesis in Mobile Multimedia

2020

The extended use of mobile multimedia devices in applications like gaming, 3D video and audio reproduction, immersive teleconferencing, or virtual and augmented reality, is demanding efficient algorithms and methodologies. All these applications require real-time spatial audio engines with the capability of dealing with intensive signal processing operations while facing a number of constraints related to computational cost, latency and energy consumption. Most mobile multimedia devices include a Graphics Processing Unit (GPU) that is primarily used to accelerate video processing tasks, providing high computational capabilities due to its inherent parallel architecture. This paper describes…

Iterative geometric modelling and new world of shapes

2010

Mes recherches ont pour cadre la modélisation géométrique pour la Conception Assistée par Ordinateur et la Synthèse d'images. Plus précisément, j'étudie les possibilités qu'offrent les procédés de construction itératifs basés sur le principe de la géométrie fractale. Partant du modèle IFS (Iterated Function System), nous avons montré qu'il est possible de modéliser des formes non conventionnelles et ainsi de donner accès à un nouvel univers de formes aux concepteurs, artistes et designers. Cette approche est notamment utilisée pour modéliser des surfaces plissées (comme pour la réalisation de coques en architecture) ou des surfaces rugueuses. Nous avons orienté nos travaux sur la notion de …

Who are the Showroomers? Socio-Demographic Factors Behind the Showrooming Behavior on Mobile Devices

2022

This quantitative study focuses on socio-demographic variables and their associations with different forms of showrooming behavior. The purpose of this study is to find which consumer groups based on age, gender, and income level are demographically the most probable showroomers, and how much each of these variables explain showrooming. The data used is a structured online survey from 1,028 Finnish omnichannel consumers aged between 18 and 75 years. We compare the means of demographic groups’ shares on different aspects of showrooming, and then use partial least squares structural equation modeling with confirmatory factor analysis to see how much each of the variables explain showrooming. …

On Photometric Analog Computers for Statistical Purposes

1959

AUGMENTED REALITY FOR CULTURAL HERITAGE: THE REBIRTH OF A HISTORICAL SQUARE

2019

Abstract. The case study, faced in this paper, arises in the context of Interreg Italia-Malta European project named I-Access, dedicated to the improvement of accessibility to Cultural Heritage (CH). Accessibility considered not only as the demolition of physical architectural barriers, but also as the possibility of fruition of CH through technological tools that can increase its perception and knowledge. Last achievements in photogrammetry and terrestrial laser scanner (TLS) technology offered new methods of data acquisition in the field of CH, giving the possibility of monitoring and processing big data, in the form of point clouds. Ever in this field, reverse engineering techniques and …

HIGH QUALITY TEXTURE MAPPING PROCESS AIMED AT THE OPTIMIZATION OF 3D STRUCTURED LIGHT MODELS

2019

Abstract. This article presents the evaluation of a pipeline to develop a high-quality texture mapping implementation which makes it possible to carry out a semantic high-quality 3D textured model. Due to geometric errors such as camera parameters or limited image resolution or varying environmental parameters, the calculation of a surface texture from 2D images could present several color errors. And, sometimes, it needs adjustments to the RGB or lightness information on a defined part of the texture. The texture mapping procedure is composed of mesh parameterization, mesh partitioning, mesh segmentation unwraps, UV map and projection of island, UV layout optimization, mesh packing and mes…

3D MODELING of A COMPLEX BUILDING: From MULTI-VIEW IMAGE FUSION to GOOGLE EARTH PUBLICATION

2019

Abstract. This paper presents a pipeline that aims at illustrating the procedure to realize a 3D model of a complex building integrating the UAV and terrestrial images and modifying the 3D model in order to publish to Google Earth in an interactive modality so as to provide better available models for visualization and use. The main steps of the procedure are the optimization of the UAV flight, the integration of the different UAV and ground floor images and the optimization of the model to be published to GE. The case study has been identified in a building, The Eremo di Santa Rosalia Convent in Sicily which hash more staggered elevations and located in the hills of the hinterland and of w…

MODELLING VAGUE KNOWLEDGE FOR DECISION SUPPORT IN PLANNING ARCHAEOLOGICAL PROSPECTIONS

2012

Abstract. Most archaeological predictive models lack significance because fuzziness of data and uncertainty in knowledge about human behaviour and natural processes are hardly ever considered. One possibility to cope with such uncertainties is utilization of probability based approaches like Bayes Theorem or Dempster-Shafer-Theory. We analyzed an area of 50 km2 in Rhineland Palatinate (Germany) near a Celtic oppidum by use of Dempster-Shafer's theory of evidence for predicting spatial probability distribution of archaeological sites. This technique incorporates uncertainty by assigning various weights of evidence to defined variables, in that way estimating the probability for supporting a …