Real-Time Digital Image Processing for Radiological Imaging

Abstract

Advances in semiconductor memory and microprocessor technology combined with significant cost reductions for these devices have made it technically feasible to develop high-speed, high-performance, stand-alone digital imaging equipment. The paper describes the design and operation of a digital image processing unit that provides several significant image improvement capabilities especially important to radiological imaging. Among these capabilities are noise averaging, image differencing or comparison, contrast transfer modification, spatial filtering, and edge enhancement. Most of these operations are performed at television rates in real time without resort to off-line processing in an associated computer. However, the units own random-access digital memory can be time-shared with an external central processing unit for additional processing through software. Examples of application to X-ray and neutron radiography are presented, including processing of very-low-contrast imagery. The discussion includes also an analysis of the signal-to-noise ratio improvement that is attainable with equipment of this type.