Edge detection within qualitative phase contrast neutron radiographies of castings

Qualitative phase contrast (QPC) imaging is a powerful tool to assess objects or composites with low or nearly the same attenuation coefficient resulting in a low absorption contrast. QPC imaging provides additional information like enhanced contrast at edges and interfaces as well as the possibility to separate materials with similar attenuation coefficients. The measurements are carried out at the neutron radiography facility ANTARES (Advanced Neutron Tomography and Radiography Experimental System), which fulfills the requirements for QPC imaging: a high transversal spatial coherence and a detector plane in the near-field region. We take QPC tomographies of a specially designed aluminum casting. In this work, the focus is on the image processing of QPC neutron radiographies, especially on edge and line detection and separation. For our purpose, we have evaluated different state of the art 2-D edge detection algorithms. Among our tested image post-processing algorithms, the best suitable procedure for edge and line detection on large and small scales have been identified.     «

Qualitative phase contrast (QPC) imaging is a powerful tool to assess objects or composites with low or nearly the same attenuation coefficient resulting in a low absorption contrast. QPC imaging provides additional information like enhanced contrast at edges and interfaces as well as the possibility to separate materials with similar attenuation coefficients. The measurements are carried out at the neutron radiography facility ANTARES (Advanced Neutron Tomography and Radiography Experimental Sy...     »