ISSN: 0022-1198
CODEN: JFSCA
Published Online: 1 September 2002
Page Count: 8

A Discrimination Method for Paper by Fourier Transform and Cross Correlation
Miyata, H
Research associate, Criminal Investigation Laboratory,

Shinozaki, M
Research associate, Oji Paper Co. Ltd., Advanced Technology Research Laboratory,

Enomae, T
Assistant professor, Graduate School of Agriculture and Life Science, Laboratory of Pulp & Paper Science, The University of Tokyo,

Nakayama, T
Graduate student, Graduate School of Agriculture and Life Science, Laboratory of Pulp & Paper Science, The University of Tokyo,

(Received 10 April 2002; accepted 6 April 2002)

Abstract

A non-destructive method for discriminating between different types of paper has been proposed, using image analysis, Fourier transformation, and cross-correlation matching. A fast Fourier transform (FFT) is used to extract the periodicity in the structure of paper that results from the manufacturing processes. The light-transmission images of the paper to be Fourier transformed are obtained from a flatbed image scanner. The similarity between the power spectrum of the FFT of the sample and that of a reference is quantified using a cross-correlation matching method. An advantage of using frequency analysis is that periodicity can be detected even if the sample is damaged or is printed on. The technique works on samples as small as 2 cm 2 .

Keywords:
forensic science, questioned document, image analysis, paper formation, Fourier transform, cross-correlation, non-destructive testing

Paper ID: JFS15491J
DOI: 10.1520/JFS15491J
ASTM International is a member of CrossRef.