An advanced processing method of ECT images based on defect-orientations

Issue title: Special Volume: Proceedings of the eleventh International Symposium on Applied Electromagnetics and Mechanics ISEM-Versailles ISEM 03

Article type: Research Article

Authors: Taniguchi, Tetsuki^a | Nakamura, Kazunori^b | Yamada, Sotoshi^{b; *} | Iwahara, Masayoshi^b

Affiliations: [a] Department of Electronic Engineering, The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo, 182-8585 Japan. Tel.: +81 3 43 5192; Fax: +81 3 43 5210; E-mail: taniguch@ee.uec.ac.jp | [b] Institute of Nature and Environmental Technology, Kanazawa University 2-40-20 Kodatsu-no, Kanazawa, 920-8667 Japan. Tel.: +81 762 234 4942; Fax: +81 762 234 4946; E-mail: yamada@magstar.ec.t.kanazawa-u.ac.jp

Correspondence: [*] Corresponding author. E-mail: tsuchida@cc.oita-u.ac.jp

Abstract: This paper presents a novel procedure for eddy-current image processing based on defect-orientations. First, nonlinear filtering technique is used to eliminate the noise and offset component in the ECT signals keeping the shape of defect-origined signals. Then the direction finding and the pattern matching methods are carried out to find the position of the defect with a specific direction. Based on the derived information, the classification of defects and image synthesis are carried out. Through an application to images derived from samples having defects in various orientations, the effectiveness of the proposed method is verified.

Keywords: eddy-current testing, nondestructive evaluation, image processing, nonlinear filtering

DOI: 10.3233/JAE-2004-599

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 19, no. 1-4, pp. 405-408, 2004