Cracklike defects sizing from co-occurrence matrix

Author

Moysan, J. ; Corneloup, G. ; Magnin, I. ; Benoist, P. ; Basset, O.

Author_Institution

Lab. de Controle par UltraSons, CENS, Gif sur Yvette, France

fYear

1990

fDate

4-7 Dec 1990

Firstpage

1147

Abstract

The inspection of austenitic welds used in the nuclear field with ultrasound involves problems of interpretation: intense grain noise makes the detection of the crack difficult. The formation B-scan images and their digital processing increase the effectiveness of testing. A segmentation method based on the cooccurrence matrix is presented. It separates defect zones and noise zones. The calculation of statistical parameters makes it possible to automate and to improve image thresholding. Defect sizing through the analysis of the modified image is the final goal. Some examples of segmentation improvement applied to artificial defects are presented

Keywords

austenitic steel; crack detection; ultrasonic materials testing; welding; B-scan images; artificial defects; austenitic welds; cooccurrence matrix; cracklike defects sizing; defect zones; digital processing; grain noise; image thresholding; modified image; noise zones; nuclear field; segmentation method; statistical parameters; ultrasound; Histograms; Image analysis; Image segmentation; Inspection; Laboratories; Sorting; Symmetric matrices; Testing; Ultrasonic imaging; Welding;

fLanguage

English

Publisher

ieee

Conference_Titel

Ultrasonics Symposium, 1990. Proceedings., IEEE 1990

Conference_Location

Honolulu, HI

Type

conf

DOI

10.1109/ULTSYM.1990.171542

Filename

171542