In materials physics, X-ray image of organometallic composites and other materials are often severely degraded by superimposed noise due to scattered radiation and by the limited spatial frequency response of the instrumentation. The authors investigate the effect of a simple and fast digital enhancement procedure for images acquired by energy dispersive X-ray analysis in electron microscopy. The degree of image enhancement possible is demonstrated on a number of typical specimens. In the first example, analysis of an X-ray map shows ill-defined manganese dioxide particles suspended in polymer; in the second example, the procedure is used to highlight and delineate the pattern of corrosion on gas turbine blades. The flexibility of the approach is tested by further application to examples illustrating different imaging modalities encounted in nuclear medicine.

The nonlinearity of the video display, together with variations in brightness and contrast arising from variability in the data, will affect the visual discrimination of features of interest. The loss of displayed information is due to environmental and instrumentation effects, and can be partially corrected for in real-time (i.e. at video frame rates) if the data is digitized and approriately normalized. Methods are described for normalizing the contrast and brightness of video displays and for correcting for luminance compression. Experimental results for a sidescan sonar display demonstrate that statistical normalization and gamma-compensation improve the visibility of seabed features and therefore the reliability of visual search during seabed surveillance. Zusammenfassung. Die Un-linearität des Videobildes, zusammen mit den aus der Variabiltät in den Daten herrührenden Variationen in Helligkeit und Kontrast, wird die visuelle Diskriminierung von interessanten Merkmalen beeinflussen. Der Verlust in bildlich dargestellter Information beruht auf Umwelts - und Instrumentierungs - Effekten, und kann teilweise für Echtzeit (d.h. Videobildgeschwindigkeit) korrigiert werden, falls die Daten digital dargestellt und sachgemäss normaliziert sind. Beschrieben sind Methoden für das Normalizieren von Kontrast und Helligkeit des Videobildes und für das Korrigieren der Leuchtkraft - Kompression. Versuchsresultate für ein seitenabsuchendes Echolot - Bild demonstrieren, dass statistische Normalizierung und Gamma - Kompensation die Klarheit der Meeresgrund - Besonderheiten, und damit die Verläss-lichkeit des visuellen Absuchens während einer Meeresgrund - Überwachung, verbessern.

A need exists for improving the current methods for ensuring the safety of ammunition fuzes. Accordingly the feasibility of using automatic techniques for the inspection of ammunition fuzes has been investigated. The investigation covered the following aspects. (1) The usefulness of image enhancement techniques for the improvement of the detectability of defects; (2) the feasibility of automatic recognition of defects: and (3) the merits and the practicability of using real-time radiography to replace the filmbased system for fuze inspection. It may be concluded from the feasibility study that image qualities can be significantly enhanced for visual detection. When a defect can be characterised in terms of the intensity and geometrical factors of its radiographic images automatic identification of the defect also appears to be feasible. The assessment also indicated that the use of real-time radiography is now a practical proposition.

The application of digital image processing to mass screening for breast cancer is demonstrated in the context of adaptive spatial filtering. Experimental results for feature extraction by texture analysis and grey level thresholding reveal there is significant potential for computer-aided mass screening as an adjunct to radiological examination. Digital image processing can improve the visibility of image features, such as neoplasms or tumours, providing also speed and automation of inspection, whilst saving the radiologist time which is otherwise spent on checking clear samples (which represent the majority of screening cases). Zusammenfassung. Die Anwendung ziffernmäßiger Bildbearbeitung zur Massenabblendung für Brustkrebs wird im Zusammenhang mit räumlichem Filtern demonstriert. Experimentresultate für Besonderheiten-Extraktion im Falle von Gewebeanalyse und Grau-Niveaubegrenzung enthüllen, daß hier eine bedeutende Möglichkeit für computer-unterstützte Massenabblendung als ein Zusatz zur radiologischen Untersuchung besteht. Ziffernmäßige Bildbearbeitung kann die Sichtbarkeit von Bildmerkmalen, wie Neoplasmen und Tumoren, verbessern, außerdem Geschwindigkeit und Automation der Inspektion bietend, während dem Radiologen Zeit ersparend, die andernfalls zur Überprüfung klarer Muster verwendet würde (was für die Mehrzahl der Abschirmfälle zutrifft).