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science, Morocco

Aqel S.,LESSI | Sabri A.,LIIAN | Aarab A.,LESSI
International Review on Computers and Software | Year: 2015

Moving objects detection in a scene from a video sequence is a fundamental and crucial problem in many vision systems such as video surveillance or the traffic monitoring. Background modeling is often used to detect moving objects which assumes that the moving objects take less time in the scene with respect to the background. Indeed, this assumption cannot be valid in case of a scene with fast moving objects. To overcome this problem, in this paper we propose a novel background modeling approach based on transitions intensities. In other words, we will focus on intensity changes (transitions) ofpixels during a scene instead of using duration information that a pixel pass in a state without any notable change in its intensity. The normalized RGB color is used to describe the appearance under change lighting conditions, and transition intensity is introduced to capture the dynamicity of objects over time. Experimental results on different video sequences have been presented to approve the effectiveness of the proposed algorithm. © 2015 Praise Worthy Prize S.r.l. - All rights reserved.


Jeghal A.,LIIAN | Oughdir L.,University Sidi Mohammed Ben Abdellah | Tairi H.,LIIAN | El Affar A.,University Sidi Mohammed Ben Abdellah
Journal of Theoretical and Applied Information Technology | Year: 2013

The use of learner profiles is one of the ways to adapt learning to the learners' specifics, as the computing environments for Human Learning (EIAH) allow users to view the learner profiles and perform activities on their visualizations. We are interested in the reuse of heterogeneous profiles coming from different platforms. Our goal is to propose models and tools to enable or to allow the reuse of external profiles. In this article we present a state of the art on the existing models and our proposed model. © 2005 - 2013 JATIT & LLS. All rights reserved.


El Batteoui I.,LIIAN | Saaidi A.,LIIAN | Saaidi A.,University Sidi Mohammed Ben Abdellah | Satori K.,LIIAN
Journal of Theoretical and Applied Information Technology | Year: 2013

In this paper, an unknown planar scene is used to auto-calibrate a camera with variable intrinsic parameters. The images are obtained by changing the zoom of the camera giving the calibration matrices different from one view to another. The principal idea of our method reside in the use three matches only between three images of the planar scene for computing the projection matrix of a parallelogram and the application to the camera a pure rotation giving other equations of self-calibration.The computing of the projection matrix in the ith image leads us to establish a mathematical relationship between it and the image of the absolute conic in the same view. That is said, a non-linear cost function is formulated whose minimization allows us to estimate the parameters of the image of the absolute conic and consequently the elements of each calibration matrix can be determined from those of the image of the absolute conic. The experimental results show the effectiveness of our approach in terms of robustness, convergence and stability. © 2005 - 2013 JATIT & LLS. All rights reserved.


Gmira F.,LIIAN | Hraoui S.,LIIAN | Saaidi A.,LIIAN | Saaidi A.,LSI Inc | And 2 more authors.
International Journal of Tomography and Simulation | Year: 2016

The Hill Cipher algorithm has many benefits in the field of image encryption. Nevertheless, the conventional algorithm is susceptible to a plaintext attack; furthermore, Hill cipher in image encryption does not dissimulate all image features because it reveals patterns in the cipher-image, especially for images with homogeneous background. To overcome these issues, in this paper, we propose a modified Hill Cipher algorithm by including a shifting and introducing a dynamic key into each stage of the cipher. The simulation carried out of this variant adapted to the image encryption clearly indicates that the proposed variant gives better encryption of all types of images. © 2016 by CESER PUBLICATIONS.


Merras M.,LIIAN | El Akkad N.,LIIAN | Saaidi A.,LIIAN | Nazih A.G.,LIIAN | Satori K.,LIIAN
WSEAS Transactions on Computers | Year: 2014

In this paper, we propose an approach based on improved genetic algorithms for the camera calibration having the varying parameters. The present method is based on the formulation of a nonlinear cost function from the determination of the relationship between points of the image planes and all parameters of the cameras. The minimization of this function by a genetic approach enables us to simultaneously estimate the intrinsic and extrinsic parameters of different cameras. Comparing to traditional optimization methods, the camera calibration based on improved genetic algorithms can avoid being trapped in a local minimum and does not need the initial value. The proposed technique to find the near optimal solution without the need for initial estimates of the cameras parameters. Tested on several cases, the proposed method proved to be an effective tool to determine the camera parameters necessary for various applications, such as the images rectification, the analytical photogrammetry and 3D reconstruction from 2D images.

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