Download or read book Reconnaissance de L criture Manuscrite En ligne Par Approche Combinant Syst mes Vastes Marges Et Mod les de Markov Cach s written by Abdul Rahim Ahmad and published by . This book was released on 2008 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Handwriting recognition is one of the leading applications of pattern recognition and machine learning. Handwriting recognition systems have been used as an imput method of many electronic devices and helps in the automation of many manual tasks. To further open the avenues of expanding its applications, specific improvements need to be made in the recognition capability of the system. Hidden Markov Model (HMM) has been the dominant methods of the recognition in handwriting recognition in offline and online systems. However, the use of Gaussian observation densities in HMM and representational model for word modeling often does not lead to good classification. Hybrid of Neural Network (NN) and HMM later improves word recognition by taking advantage of NN discriminative property and HMM representational capability. However, the use of NN does not optimize recognition capability as the use Empirical Risk minimization (ERM) principle in its training leads to poor generalization. In this thesis, we focus on improving the recognition capability of a cursive online handwritten word recognition system by using an emerging method in machine learning, the support vector machine (SVM). We first evaluated SVM in isolated character recognition environment using IRONOFF and UNIPEN character databases. SVM, by its use of principle of structural risk minimization (SRM) have allowed simultaneous optimization of representational and discriminative capability of the character recognizer. We finally demonstrate the various practical issues in using SVM within a hybrid setting with HMM. In addition, we tested the hydrid system of the IRONOFF word database and obtained satisfactory results.

Download or read book Reconnaissance de L criture Manuscrite Multi Scripts written by Yousri Kessentini and published by Omniscriptum. This book was released on 2010-08 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: Les travaux pr sent s dans ce livre concernent le d veloppement et l' valuation d'un syst me de reconnaissance de l' criture manuscrite multi- scripts. L'objectif est de proposer un syst me de reconnaissance op rant ind pendamment de la nature du script. Pour cela l'approche propos e est sans segmentation explicite, ceci afin de ne pas introduire une technique de conditionnement de l'information d pendant du type d' criture analys e. Des caract ristiques bas niveaux sont combin es travers une approche multi-flux permettant de combiner d'une mani re asynchrone, diff rentes sources d'information travers des mod les de Markov coop ratifs. Des extensions des r gles de combinaison sont envisag es dans le cadre de la th orie des fonctions de croyances transf rables. L' valuation du syst me de reconnaissance propos est men e sur diff rentes bases de donn es de r f rence correspondant aux deux scripts Arabe (IFN-ENIT) et Latin (IRONOFF et RIMES). Les r sultats montrent que le syst me propos donne de bons r sultats aussi bien sur le Latin que sur l'Arabe comparables ceux des meilleurs syst mes pr sent s dans la litt rature.