Style Characterization of Machine Printed Texts

Transcription

1 Style Characterization of Machine Printed Texts Andrew D. Bagdanov

2 This book is typeset by the author using L A TEX2 ε. The main body of the text is set using the Computer Modern family of fonts. The images and figures are included in the text in encapsulated Postscript format TM Adobe Systems Incorporated. Printing: Febodruk BV, Enschede, The Netherlands. Copyright c 2004 by Andrew D. Bagdanov. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without written permission from the author. ISBN X

3 Style Characterization of Machine Printed Texts ACADEMISCH PROEFSCHRIFT ter verkrijging van de graad van doctor aan de Universiteit van Amsterdam, op gezag van de Rector Magnificus prof. mr. P.F. van der Heijden ten overstaan van een door het College voor Promoties ingestelde commissie, in het openbaar te verdedigen in de Aula der Universiteit op woensdag 26 mei 2004 te uur door Andrew David Bagdanov geboren te Burbank, Californië, Verenigde Staten van Amerika

4 Promotiecommissie: Promotor: Co-promotor: Prof. dr. ir. A.W.M. Smeulders dr. M. Worring Overige leden: Prof. dr. P. van Emde Boas Prof. dr. ir. F.C.A. Groen Prof. dr. G. Nagy Prof. dr. ir. R.J.H. Scha dr. T. Gevers dr. R. Hamberg dr. ir. H.J.A.M. Heijmans Faculteit: Faculteit der Natuurwetenschappen, Wiskunde & Informatica Kruislaan SJ Amsterdam Nederland The work described in this thesis was supported by the ICES-KIS MIA-project and Océ Nederland. Advanced School for Computing and Imaging The work described in this thesis has been carried out within graduate school ASCI, at the Intelligent Sensory Information Systems group of the University of Amsterdam. ASCI dissertation series number 102.

5 This dissertation is dedicated to my mother and the memory of my father.

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7 Contents 0 Prelude 1 1 Introduction Elementsofstyle Contextandscope Context Scope Organization of this thesis Characterizing layout style using first order Gaussian graphs Definitions and basic concepts First order Gaussian graphs Technicalities Reflections Clustering and classification Hierarchical clustering of FOGGs Classification using first order Gaussian graphs Experiments Test data Classifiers Experimental results Computational efficiency Analysis Discussion Multi-scale visual style characterization with rectangular granulometries Documentgenre Granulometries Document representation Rectangular size distributions Efficiency Feature space reduction and interpretation Experimentalresults Genre classification Document image retrieval i

8 ii CONTENTS 3.5 Discussion Probing textual style with local vertical granulometries Another look at granulometries The key observation Introducing localization An efficient word spotter AGenerative model Glyph distributions Agenerative word model Experiments and illustration Typeface classification Word spotting Discussion Autocorrelation-driven restoration of scanned color halftones Halftone process color Halftone color reproduction Scanned color halftones Diffusion of scanned color halftones Linear diffusion filtering Nonlinear diffusion filtering Measuring local autocorrelation Experiments Discussion A functional approach to software design in image processing research environments Introduction Acritique of pure reason Analysis Design considerations Goals Choice of language Previous work Architecture Primitive types and operations Types and typing Primitive image operations Backend substitution Casestudies Linear scalespace Complete lattice morphology An algebraic expression compiler Discussion...128

9 CONTENTS iii 7 Summary and concluding remarks Summary Concludingremarks Bibliography 135 Samenvatting 143 Acknowledgements 145

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