NEW APPROACH FOR 3D OBJECT RECOGNITION USING NON UNIFORM FOURIER AND MOMENTS COEFFICIENTS

In this paper, new descriptors have been proposed which are invariant to rotation and affinity transformations (Non Uniform Fourier and moments coefficients). These descriptors are computed using Fourier or moments coefficients obtained from development of object coordinates. These coordinates are parameterized with a function also invariant to affinity. The normal Fourier transform depends on points index, the Non Uniform transform proposed here depend on a parameter. This parameter depends on shape not on order of points. The proposed descriptors are easy to extract and are extensible to higher dimension

Estimation des paramètres d'un mouvement affine utilisant les descripteurs de fourier

- Dans cette communication nous présentons un algorithme d'estimation de mouvement affine. Cet algorithme est capable d'estimer non seulement la translation, la rotation mais aussi les étirements. Nous utilisons la longueur affine pour la normalisation du profil extérieur d'un objet en mouvement. Ce profil sera ensuite décrit par les Descripteurs de Fourier (DF) correspondants. Une telle description permet dans un premier temps la définition d'une erreur entre DFs de deux objets en mouvement liés par une affinité, ensuite l'estimation de cette affinité par minimisation de cette erreur

Uses of Augmented reality for urban utilities management

Augmented reality (AR) is based on supplementing the view of the physical world with a computer-generated content such as text, images videos, sound, 3D objects etc. The proliferation of smart mobile devices and their high computational capabilities combined with the possibility of GIS 3D visualization and interaction have enabled new kinds of mobile applications. AR is considered as an efficient technology for the underground utilities management. Damages to underground utility lines are considered as one of the major urban problems because incidents caused by unsafe digging practices can compromise community safety and disconnect people from vital services. A prospective study was conducted to identify examples and characteristics of each type of augmented reality. This paper summarizes researches about the types of AR and discuss how this technology could help in underground utilities repairing and maintenance. We present a new mobile location based augmented reality system using smart device sensors and the Real Time Kinematic (RTK) satellite navigation technology of ORPHEON network for the location accuracy. This system enables GIS data visualization to help field workers in outdoor maintenance of underground infrastructures

Main problems and proposed solutions for improving Template Matching

In this work we discuss the problems of template matching and we propose some solutions.  Those problems are: 1) Template and image of search differ by a scale, 2) Template or image of search is object of rotation, 3) Template or image of search is object of an affinity. The well known method is NCC (Normalized Cross Correlation); this method can not handle scale, rotation, affinity or occlusion. Also the NCC is not preferred for binary image. So we propose here to use index similarity for example Jaccard index

A Visual Similarity-Based 3D Search Engine

Retrieval systems for 3D objects are required because 3D databases used around the web are growing. In this paper, we propose a visual similarity based search engine for 3D objects. The system is based on a new representation of 3D objects given by a 3D closed curve that captures all information about the surface of the 3D object. We propose a new 3D descriptor, which is a combination of three signatures of this new representation, and we implement it in our interactive web based search engine. Our method is compared to some state of the art methods, tested using the Princeton-Shape Benchmark as a large database of 3D objects. The experimental results show that the enhanced curve analysis descriptor performs well

A 3-D Search engine based on Fourier series

International audienceThe size of 3-D data stored around the Web has become bigger. Therefore the development of recognition applications and retrieval systems of 3-D models is important. In this paper we propose a new scheme to measure similarity between 3-D models. The main idea is to reconstruct a 3-D closed curve that represents a 3-D model given by a polygonal mesh, and to extract a signature from this 3-D closed curve using the Fourier series. The proposed descriptor needs continuous principal component analysis (CPCA) to align 3-D models into a canonical position. The feature vectors constructed using this method, named Fourier series descriptor (FSD) are invariants under rigid transformations composed of translation, rotation, flipping and scale; robust to noise and level of detail. A 3-D polygonal mesh model serves as a query for search by shape similarity in a large collection of 3-D models database using an interactive 3-D search engine