Recognizing Degraded Handwritten Characters

In this paper, Slavonic manuscripts from the 11th century written in Glagolitic script are investigated. State-of-the-art optical character recognition methods produce poor results for degraded handwritten document images. This is largely due to a lack of suitable results from basic pre-processing steps such as binarization and image segmentation. Therefore, a new, binarization-free approach will be presented that is independent of pre-processing deficiencies. It additionally incorporates local information in order to recognize also fragmented or faded characters. The proposed algorithm consists of two steps: character classification and character localization. Firstly scale invariant feature transform features are extracted and classified using support vector machines. On this basis interest points are clustered according to their spatial information. Then, characters are localized and eventually recognized by a weighted voting scheme of pre-classified local descriptors. Preliminary results show that the proposed system can handle highly degraded manuscript images with background noise, e.g. stains, tears, and faded characters

Observed methods of cuneiform tablet reconstruction in virtual and real world environments

The reconstruction of fragmented artefacts is a tedious process that consumes many valuable work hours of scholars' time. We believe that such work can be made more efficient via new techniques in interactive virtual environments. The purpose of this research is to explore approaches to the reconstruction of cuneiform tablets in the real and virtual environment, and to address the potential barriers to virtual reconstruction of fragments. In this paper we present the results of an experiment exploring the reconstruction strategies employed by individual users working with tablet fragments in real and virtual environments. Our findings have identified physical factors that users find important to the reconstruction process and further explored the subjective usefulness of stereoscopic 3D in the reconstruction process. Our results, presented as dynamic graphs of interaction, compare the precise order of movement and rotation interactions, and the frequency of interaction achieved by successful and unsuccessful participants with some surprising insights. We present evidence that certain interaction styles and behaviours characterise success in the reconstruction process

Rekonstruksi Kertas Sobek Berbasis Corner Point (Studi Kasus: Sobekan Digital)

Kertas merupakan media yang digunakan sebagai wadah untuk menampung kreatifitas, gagasan, dan catatan penting yang telah digunakan sejak jaman dahulu. Banyak catatan berharga yang berada di atas kertas seperti surat perjanjian, catatan sejarah, laporan, dan lain sebagainya. Dokumen berharga tersebut bisa saja rusak entah karena sengaja ataupun tidak sengaja. Penyebab rusaknya dokumen ada bermacam-macam dan salah satunya adalah akibat sobek. Tugas akhir ini menggunakan corner point yang diperoleh menggunakan Harris Corner Detection sebagai solusi untuk merekonstruksi kertas yang sobek. Selisih sudut dan jarak antar corner point dibandingkan dengan threshold tertentu untuk menentukan kandidat pasangan sobekan. Persentase pasangan corner kandidat tersebut dibandingkan dengan decision threshold untuk memastikan bahwa pasangan sobekan tersebut merupakan pasangan yang tepat atau bukan. Affine Transform digunakan untuk merekonstruksi dan menggabungkan pasangan sobekan kertas dengan dibantu oleh RANSAC. Berdasarkan penelitian yang dilakukan, pasangan sobekan dapat ditentukan dengan membandingkan besar sudut dan jarak antar titik pembentuk sudut tersebut yang dihasilkan oleh Harris Corner Detection. Decision threshold yang dibentuk berdasarkan persentase pasangan corner yang cocok mampu memilah sobekan yang berpasangan dan sobekan yang tidak memiliki pasangan sehingga sistem mampu merekonstruksi kertas dengan baik

3D Pedestrian Tracking and Virtual Reconstruction of Ceramic Vessels Using Geometric and Color Cues

Object tracking using cameras has many applications ranging from monitoring children and the elderly, to behavior analysis, entertainment, and homeland security. This thesis concentrates on the problem of tracking person(s) of interest in crowded scenes (e.g., airports, train stations, malls, etc.), rendering their locations in time and space along with high quality close-up images of the person for recognition. The tracking is achieved using a combination of overhead cameras for 3D tracking and a network of pan-tilt-zoom (PTZ) cameras to obtain close-up frontal face images. Based on projective geometry, the overhead cameras track people using salient and easily computable feature points such as head points. When the obtained head point is not accurate enough, the color information of the head tops across subsequent frames is integrated to detect and track people. To capture the best frontal face images of a target across time, a PTZ camera scheduling is proposed, where the 'best' PTZ camera is selected based on the capture quality (as close as possible to frontal view) and handoff success (response time needed by the newly selected camera to move from current to desired state) probabilities. The experiments show the 3D tracking errors are very small (less than 5 cm with 14 people crowding an area of around 4 m2) and the frontal face images are captured effectively with most of them centering in the frames. Computational archaeology is becoming a success story of applying computational tools in the reconstruction of vessels obtained from digs, freeing the expert from hours of intensive labor in manually stitching shards into meaningful vessels. In this thesis, we concentrate on the use of geometric and color information of the fragments for 3D virtual reconstruction of broken ceramic vessels. Generic models generated by the experts as a rendition of what the original vessel may have looked like are also utilized. The generic models need not to be identical to the original vessel, but are within a geometric transformation of it in most of its parts. The markings on the 3D surfaces of fragments and generic models are extracted based on their color cues. Ceramic fragments are then aligned against the corresponding generic models based on the geometric relation between the extracted markings. The alignments yield sub-scanner resolution fitting errors.Ph.D., Electrical Engineering -- Drexel University, 201

3D object reconstruction using computer vision : reconstruction and characterization applications for external human anatomical structures

Tese de doutoramento. Engenharia Informática. Faculdade de Engenharia. Universidade do Porto. 201

A Survey of Techniques for Document and Archaeology Artefact Reconstruction

An automated assembling of shredded/torn documents (2D) or broken pottery (3D) will support philologists, archaeologists and forensic experts. An automated solution for this task can be divided into shape based matching techniques (apictorial) or techniques that analyze additionally the visual content of the fragments (pictorial). In the case of visual content techniques like texture based analysis are used. Depending on the application, shape matching techniques are suitable for entities of the puzzle problem with small numbers of pieces (e.g. up to 20). Also artefacts like broken and lost pieces or overlapping parts of fragments increase the error rate of shape based techniques since the matching of adjacent boundaries can fail. As a result additional features, e.g. color, document structure, have to be used. This paper presents an overview about current puzzle applications in Cultural Heritage, and introduces also the main problems in puzzle solving

Kodikologie und Paläographie im digitalen Zeitalter 2 - Codicology and Palaeography in the Digital Age 2

Der Einsatz digitaler Technik verändert den wissenschaftlichen Umgang mit der handgeschriebenen Überlieferung. Dieser Band vertieft Fragen zu Digitalisierung und Katalogisierung, zu automatischer Schrifterkennung und Schriftanalyse, und er erweitert eine Diskussion, die mit dem im letzten Jahr erschienenen ersten Band zur digitalen Handschriftenforschung angestossen worden ist: Welche Erkenntnisse können etwa naturwissenschaftliche Methoden liefern? Welche musik- und kunsthistorischen Fragestellungen lassen sich mit Hilfe moderner Informationstechnologien beantworten? Wie lassen sich Methoden einer digitalen Auswertung lateinischer Handschriften auf griechische, glagolithische oder ägyptische Texte anwenden? Der raum-zeitliche Rahmen der hier von einer internationalen Autorenschaft zusammengetragenen 22 wissenschaftlichen Beiträge reicht vom alten Ägypten bis ins Paris der Postmoderne. Mit Beiträgen von: Pádraig Ó Macháin; Armand Tif; Alison Stones, Ken Sochats; Melissa Terras; Silke Schöttle, Ulrike Mehringer; Marilena Maniaci, Paolo Eleuteri; Ezio Ornato; Toby Burrows; Robert Kummer; Lior Wolf, Nachum Dershowitz, Liza Potikha, Tanya German, Roni Shweka, Yacov Choueka; Daniel Deckers, Leif Glaser; Timothy Stinson; Peter Meinlschmidt, Carmen Kämmerer, Volker Märgner; Peter Stokes—Dominique Stutzmann; Stephen Quirke; Markus Diem, Robert Sablatnig, Melanie Gau, Heinz Miklas; Julia Craig-McFeely; Isabelle Schürch, Martin Rüesch; Carole Dornier, Pierre-Yves Buard; Samantha Saidi, Jean-François Bert, Philippe Artières; Elena Pierazzo, Peter Stokes. Einleitung von: Franz Fischer, Patrick Sahle. Unter Mitarbeit von: Bernhard Assmann, Malte Rehbein, Patrick Sahle