A METHOD FOR GENERATING GRAY SCALE TRANSFER FUNCTIONS FOR USE IN DISPLAYING A DIGITAL RADIOGRAM

A method for generating on demand a gray scale transfer curve for use in displaying an image comprised of a plurality of digital values representing pixel gray scale levels with a desired contrast and brightness. This is achieved by using a single sigmoid shaped function Y=f(X, a, b, c) resembling an H&D curve of a photographic film. The Y axis represents digital output values to be used in displaying an image, while the X axis represents input digital values representing captured image information. "a" is a number representing boundary conditions for X and Y, "b" is a first parameter controlling the location of the curve along the X axis and "c" is a second parameter controlling the slope of the curve slope. This function is used to derive a Look-Up-Table (LUT) representing a continuous GST curve having the desired contrast and brightness.