INSTICC organized the third edition of VISIGRAPP that took place in Funchal- Madeira, Portugal in January 2008 after successful previous editions. This book - cludes selected papers from VISIGRAPP 2008, the Joint Conference on Computer Vision Theory and Applications (VISAPP) and Computer Graphics Theory and - plications (GRAPP). The conference was intended to stimulate the exchange of ideas on the topics of c- puter vision and computer graphics. We received a high number of paper submissions: 374 in total for both conferences. We had contributions from more than 50 countries in all continents. This confirms the success and global dimension of these jointly organized conferences. After a rigorous double-blind evaluation method, 78 submissions were accepted as full papers. From those, 20 were selected for this book. To ensure the sci- tific quality of the contributions, these were selected from the ones that were evaluated with the highest scores by the VISIGRAPP Program Committee Members and then they were extended and revised by the authors. Special thanks go to all contributors and re- rees, without whom this book would not have been possible. VISIGRAPP 2008 also featured the comments of keynote speakers, in alphabetical order, Adrian Hilton (University of Surrey, UK), Genevieve Lucet (Computer S- vices for Research at the UNAM, Mexico), Peter Sturm (INRIA Rhone-Alpes, France) and Sharathchandra Pankanti (IBM - Exploratory Computer Vision Group, USA), who are internationally recognized researchers. The presentations represented an - portant contribution to the overall quality of the conference.

This volume constitutes the refereed proceedings of the 4th Iberian Conference on Pattern Recognition and Image Analysis, IbPRIA 2009, held in Povoa de Varzim, Portugal in June 2009.

The 33 revised full papers and 29 revised poster papers presented together with 3 invited talks were carefully reviewed and selected from 106 submissions. The papers are organized in topical sections on computer vision, image analysis and processing, as well as pattern recognition.

This book includes selected papers from VISIGRAPP 2007, the Joint Conference on Computer Vision and Computer Graphics, comprising two component conferences, namely, the International Conference on Computer Vision Theory and Applications (VISAPP) and the International Conference on Computer Graphics Theory and App- cations (GRAPP), held in Barcelona, Spain, during March 8-11, 2007. We received quite a high number of paper submissions: 382 in total for both conf- ences. We had contributions from more than 50 countries in all five continents. This confirms the success and global dimension of these jointly organized conferences. After a rigorous double-blind evaluation method, a total of 78 submissions were accepted as full papers. From those, 18 got selected for inclusion in this book. To ensure the sci- tific quality of the contributions, these were selected from papers that were evaluated with the highest scores by the VISIGRAPP Program Committee members and then they were extended and revised by the authors. Special thanks go to all contributors and re- rees, without whom this book would not have been possible. VISIGRAPP 2007 included four invited keynote lectures, presented by internati- ally recognized researchers. The presentations represented an important contribution to increasing the overall quality of the conference. We would like to express our - preciation to all invited keynote speakers, in alphabetical order: Jake K. Aggarwal (The University of Texas at Austin/USA), Andre Gagalowicz (INRIA/France), Wo- gang Heidrich (University of British Columbia/Canada), Mel Slater (Universitat Politecnica de Catalunya/Spain)."

This book includes extended versions of the selected papers from VISIGRAPP 2009, the International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications, which was held in Lisbon, Portugal, during February 5-8, 2009 and organized by the Institute for Systems and Technologies of Information, Control and Communication (INSTICC). VISIGRAPP comprises three component conferences, namely, the International Conference on Computer Vision Theory and Applications (VISAPP), the International Conference on Computer Graphics Theory and Applications (GRAPP), and the International Conference on Imaging Theory and Applications (IMAGAPP). VISIGRAPP received a total of 422 paper submissions from more than 50 co- tries. From these, and after a rigorous double-blind evaluation method, 72 papers were published as full papers. These figures show that this conference is now an - tablished venue for researchers in the broad fields of computer vision, computer graphics and image analysis. From the full papers, 25 were selected for inclusion in this book. The selection process was based on the scores assigned by the Program Committee reviewers as well as the Session Chairs. After selection, the papers were further revised and extended by the authors. Our gratitude goes to all contributors and referees, without whom this book would not have been possible.