XIII Scientific Symposium of Handwriting Expertise

Ολοκληρώθηκε το 13ο επιστημονικό συνέδριο που λαμβάνει χώρα κάθε δύο χρόνια στο Μπρέσλαου της Πολωνίας από το 1983.

Πολλές ευχαριστίες στον καθηγητή Kegel και στον Rafal Ciecla για την πρόσκληση και την άψογη διοργάνωση.

Τα πρακτικά θα είναι διαθέσημα το πιθανότερο τον Σεπτέμβριο, ωστόσο κατόπιν συνεννόησης, η παρουσίαση "N.Kalantzis: Paper interference in ink Raman spectra at 685nm: A preliminary report" θα είναι διαθέσημη στον ακόλουθο σύνδεσμο:

http://www.handwriting.gr/index.files/cvgr.htm#wroclaw

The 13th scientific Symposium of Handwriting Expertise, organized by the Department of Forensic Science at the University of Wroclaw has been completed.

Many thanks to professor Kegel and dr. Rafal Ciesla for the invitation and the fabulous organisation.

The proceedings will be available around Septpember, but in agreement with the organisers, the presentation "N.Kalantzis: Paper interference in ink Raman spectra at 685nm: A preliminary report" will be available at the following link: http://www.handwriting.gr/index.files/cvgr.htm#wroclaw

Download: Πρόγραμμα/Program Flyer #1 Flyer #2

Περί διαχωρισμού της γραφής διδύμων/ On the Discriminability of the Handwriting of Twins

Στο καινούργιο τευχος του Journal of Forensic Sciences ( Volume 53 Issue 2 Page 430-446, March 2008), οι Sargur Srihari, Chen Huang και Harish Srinivasan παρουσιάζουν μια εργασία με τίτλο: "Περί διαχωρισμού της γραφής διδύμων/On the Discriminability of the Handwriting of Twins ".

In the new Issue of Journal of Forensic Sciences International ( Volume 53 Issue 2 Page 430-446, March 2008),Sargur Srihari, Chen Huang and Harish Srinivasan present a paper titled: "On the Discriminability of the Handwriting of Twins".

Περίληψη/Abstract: As handwriting is influenced by physiology, training, and other behavioral factors, a study of the handwriting of twins can shed light on the individuality of handwriting. This paper describes the methodology and results of such a study where handwriting samples of twins were compared by an automatic handwriting verification system. The results complement that of a previous study where a diverse population was used. The present study involves samples of 206 pairs of twins, where each sample consisted of a page of handwriting. The verification task was to determine whether two half-page documents (where the original samples were divided into upper and lower halves) were written by the same individual. For twins there were 1236 verification cases—including 824 tests where the textual content of writing was different, and 412 tests where it was the same. An additional set of 1648 test cases were obtained from handwriting samples of nontwins (general population). To make the handwriting comparison, the system computed macro features (overall pictorial attributes), micro features (characteristics of individual letters), and style features (characteristics of whole-word shapes and letter pairs). Four testing scenarios were evaluated: twins and nontwins writing the same text and writing different texts. Results of the verification tests show that the handwriting of twins is less discriminable than that of nontwins: an overall error rate of 12.91% for twins and 3.7% for nontwins. Error rates with identical twins were higher than with fraternal twins. Error rates in all cases can be arbitrarily reduced by rejecting (not making a decision on) borderline cases. A level of confidence in the results obtained is given by the fact that system error rates are comparable to that of humans (lower than that of lay persons and higher than that of questioned document examiners [QDEs]).


http://www.blackwell-synergy.com/doi/abs/10.1111/j.1556-4029.2008.00682.x

Journal of the American Society of Questioned Document Examiners/ December 2007

Κυκλοφόρησε το νέο τεύχος του Journal of the American Society of Questioned Document Examiners (JASQDE), Volume 10, Number 2, December 2007.

Ακολουθούν τα περιεχόμενά του:

The new issue of the Journal of the American Society of Questioned Document Examiners (JASQDE), Volume 10, Number 2, December 2007 has been released.

Here are the contents:

• C.Equey, R.Marquis, W.D.Mazzella: Influence of writing posture on the Dimension of signatures
• M.Blake: Book Review: Scientific Examination of Questioned Documents
• R. Orta M., M. Ezcurra G.: Neurosciences applied to handwriting examination
• L.J.Hart, L.Miller: Microsoft Access in the Questioned Document Laboratory
• J.D.Guscott: Can you have the perfect training case?
• A.R.Singla, O.P. Jasuja, S.Kaur: The efect of water soaking on Ballpoint pen writing

Journal of the American Society of Questioned Document Examiners: http://www.asqde.org/journal_e_journal.htm

Size influence on shape of handwritten characters loops

Στο καινούργιο e-τευχος του Forensic Science International (Volume 172, Issue 1, 2 October 2007, Pages 10-16 ), οι R. Marquisa, F. Taronia, S. Bozzab και M. Schmittbuhlc παρουσιάζουν μια εργασία με τίτλο: "Size influence on shape of handwritten characters loops".

In the new Issue of Forensic Science International (Volume 172, Issue 1, 2 October 2007, Pages 10-16 ), R. Marquisa, F. Taronia, S. Bozzab & M. Schmittbuhlc rpresent a paper titled: "Size influence on shape of handwritten characters loops".

Περίληψη/Abstract:

In the practice of forensic handwriting experts, the size of the writing on a questioned document may be different from that of known samples. In this study, the hypothesis of shape invariance of handwritten closed loops across size increasing was tested. A Fourier methodology was applied to 2325 small letters (591 a loops, 547 d loops, 596 o loops and 591 q loops) and 692 enlarged letters (162 a loops, 173 d loops, 173 o loops and 184 q loops), in a population of 13 writers who were asked to write letters in their usual size and about three times larger. Most of the writers presented similar modifications when increasing the size of the loops; they produced enlarged loops significantly more round and less slanted towards the right or the left. Furthermore, a discrimination was demonstrated between the writers on the basis of the enlarged loops, with a correct classification rate superior to 90%, whatever the letter (a, d, o or q). A classification of the enlarged loops in their corresponding writer was then possible. On the contrary, when comparing the enlarged loops to the small ones, almost one half of the enlarged loops were allocated to a wrong writer. Shape invariance was thus not supported for this particular application. Consequently, when comparing documents with a different writing size, differences in loops shape should be interpreted cautiously because they may be due to a different writer, but they may also be due to an enlargement of the loops. Therefore, reference material of similar writing size to that of the questioned writing should be requested for the comparison of handwritten loops.

Σύνδεσμος/Link:
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T6W-4MRFC96-1&_user=10&_coverDate=10%2F02%2F2007&_rdoc=1&_fmt=summary&_orig=browse&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=663719975968bb7066aadfc90adff2bc

Detection of copy–move forgery using a method based on blur moment invariants loops

Στο καινούργιο e-τευχος του Forensic Science International (Volume 171, Issue 2-3, 13 September 2007, Pages 180-189 ), οι Babak Mahdian και Stanislav Saic παρουσιάζουν μια εργασία με τίτλο: "Detection of copy-move forgery using a method based on blur moment invariants".

In the new Issue of Forensic Science International (Volume 171, Issue 2-3, 13 September 2007, Pages 180-189 ), Babak Mahdian & Stanislav Saic present a paper titled: "Detection of copy–move forgery using a method based on blur moment invariants".

Περίληψη/Abstract:

In our society digital images are a powerful and widely used communication medium. They have an important impact on our life. In recent years, due to the advent of high-performance commodity hardware and improved human–computer interfaces, it has become relatively easy to create fake images. Modern, easy to use image processing software enables forgeries that are undetectable by the naked eye. In this work we propose a method to automatically detect and localize duplicated regions in digital images. The presence of duplicated regions in an image may signify a common type of forgery called copy–move forgery. The method is based on blur moment invariants, which allows successful detection of copy–move forgery, even when blur degradation, additional noise, or arbitrary contrast changes are present in the duplicated regions. These modifications are commonly used techniques to conceal traces of copy–move forgery. Our method works equally well for lossy format such as JPEG. We demonstrate our method on several images affected by copy–move forgery.

Σύνδεσμος/ Link: http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T6W-4MJBTMV-1&_user=10&_coverDate=09%2F13%2F2007&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=92226831e72dc0baba6bf5b34d7f952f

Journal of Forensic Sciences/ July 2007

Κυκλοφόρησε το νέο τεύχος του Journal of Forensic Sciences (JOFSC), Volume 52, Number 4, July 2007. Ακολουθούν τα περιεχόμενά που αφορούν τηε Δικαστική Γραφολογία:

The new issue of the Journal of Forensic Sciences (JOFSC), Volume 52, Number 4, July 2007 has been released.Here are the contents of the articles concerning Questioned Documents:

• D.L.Hammond: Validation of LAB color mode as Nondestructive Method to differentiate Black Ballpoint Pen Inks (pp.967)
• S.Sugawara: Passport Examination by Polarized Infrared Spectrum (pp. 974)

http://www.blackwell-synergy.com/toc/jfo/52/4

ABSTRACTS:

Passport Examination by Polarized Infrared Spectra

Abstract: In this study, a new nondestructive technique for passport examination is proposed. In this technique, linearly polarized light is used to measure Fourier transform infrared (FT-IR) reflectance spectra of films on the biographical data page. Thirty genuine and thirty-five counterfeit Japanese passports and five marketed films pasted on name cards were examined. The measured spectra were analyzed as follows. The absorption spectra were obtained by the Kramers–Kronig transformations of reflectance spectra. The peak ratios were then calculated from the absorption spectra by adding the peak areas at 1126 and 1263 cm1 and dividing the result by the peak area at 1727 cm1. When nonpolarized light was used, the samples could not be distinguished by comparing the peak ratios. However, when polarized light was used, they were successfully distinguished by the comparison. Therefore, polarized light is useful for the forensic discrimination of passport films by the measurement of FT-IR spectra.

Validation of LAB Color Mode as a Nondestructive Method to Differentiate Black Ballpoint Pen Inks

Abstract: Nondestructive digital processing methods such as lab color mode (available in Adobe® Photoshop®) are emerging as alternative methods for forensic document examiners to use when attempting to differentiate writing instrument inks. Although these techniques appear to be viable, little data currently exists regarding the known or potential error rates associated with these techniques. Without adequate data, the validity and reliability of these techniques, including lab color, can not be established. In an attempt to begin to address these issues, 44 black ballpoint ink pens were obtained and used to create 990 pen-pair samples for analysis using established lab color mode techniques. No erroneous findings of "different" were reported following the examination of the known pen-pair combinations in which the same pen was used to create the samples (n = 44). Of the remaining 946 samples, 737 pen-pair samples were differentiated using the lab color mode method, while 209 samples were unable to be differentiated and were recorded as either being "similar" (n = 153) or "unsure" (n = 56). Comparison of the lab color mode results with the results obtained through additional testing using traditional infrared reflectance and infrared luminescence test methods showed that lab color differentiated 102 pen-pair samples (11%; 102/946) that were not differentiated using a VSC-4C.