Separation of geometrical- and defect information in digital radiographs using wavelet filter techniques

Paper in proceeding, 2011

This paper describes the development of a mathematical model of new digital x-ray technologies and is part of a project that intends to develop an automated system for structural integrity assessment. The first part of this paper explains the exploited attenuation model based on a ray tracing assumption with piecewise linear attenuation coefficients. This is followed by a description of how the modeled volume is defined by specification of simple mathematical surfaces and the third part specifies typical welds addressed in this project. The model of a digital x-ray detector and its implementation into a simulation tool is thereafter briefly described. A thorough validation of the x-ray attenuation and the simulation software using another software PENELOPE has been conducted. The paper is concluded with an example of intended approach to remove geometrical large scale information by applying wavelet transform of the radiograph.