Advanced enhancement techniques for digitized images
Abstract
Computer image enhancement of digitized X-ray and conventional photographs has been employed to reveal anomalies in aerospace hardware. Signal processing of these images included use of specially-developed filters to sharpen detail without sacrificing radiographic information, application of local contrast stretch and histogram equalization algorithms to display structure in low-contrast areas and employment of other unique digital processing methods. Edge detection, normally complicated by poor spatial resolution, limited contrast and recording media noise, was performed as a post-processing operation via a difference-of-Gaussians method and a least squares fitting procedures. In this manner, multi-image signal processing allowed for the precise measurement (to within 0.02 inches, rms) of the Inertial Upper Stage nozzle nosecap motion during a static test firing as well as identifying potential problems in the Solid Rocket Booster parachute deployment.
- Publication:
-
IN: Symposium on Nondestructive Evaluation
- Pub Date:
- 1986
- Bibcode:
- 1986syne.proc...68T
- Keywords:
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- Augmentation;
- Digital Techniques;
- Image Enhancement;
- Image Processing;
- Nondestructive Tests;
- X Ray Imagery;
- Edges;
- Nose Tips;
- Pixels;
- Signal To Noise Ratios;
- Turbine Blades;
- Instrumentation and Photography