Digital enhancement of very low contrast radiographs
Abstract
Digital image enhancement is discussed as a means of intensifying the visualization of obscure radiographic details. Following suppression of large-scale background density variations, it is possible to develop an adaptive computer algorithm to determine the density region to be stretched for better flaw detection. This possibility is demonstrated on an image of a weld defect, where the radiograph has its background density variations removed by frequency domain filtering. Extreme stretching of the radiograph densities is then performed. Noise buildup is minimized with this procedure.
- Publication:
-
Materials Evaluation
- Pub Date:
- August 1976
- Bibcode:
- 1976MatEv..34..182J
- Keywords:
-
- Computer Techniques;
- Digital Techniques;
- Image Contrast;
- Image Enhancement;
- Nondestructive Tests;
- Radiography;
- Adaptive Filters;
- Algorithms;
- Frequency Response;
- Microdensitometers;
- Instrumentation and Photography