Software invisible selective monochrome to color signal converter for

Abstract

A medical diagnostic imaging apparatus (A) creates an image representation which is stored in an image memory (24). A video processor (26) generates a monochrome video signal from the data stored in the image memory. A monochrome to color video signal converter (B) converts the gray scale designations of the monochrome video signal to hue scale designations of a color video signal. More specifically, the gray scale values of the monochrome signal are digitized by an analog-to-digital (32) and used as addresses for a plurality of look up tables (36r, 36g, 36b, 64r, 64g, 64b). Each set of three look up tables (30, 60, 66) is preprogrammed with appropriate transfer functions, such as the transfer functions (40, 42, 44) of FIG. 2. Each look up table puts out an appropriate intensity designation for one of the three color components of the video signal. A digital-to-analog converter (50) converts the look up table outputs to three components of an RGB or other appropriate color video signal. Switches (72) are controlled by a switch controller (74) to switch among two or more sets of look up tables during each frame of the monochrome video signal. Each seat of look up tables has different transfer functions, such as a monochrome to color transfer function and a monochrome to monochrome transfer function. In this manner, some quadrants or other regions (78a, 78b, 78c, 78d) of the video display on a video monitor (C) are in color and other quadrants are in black and white. This enables multiple diagnostic images to be displayed concurrently in quadrants of the video display in either a monochrome or color format--whichever is more appropriate to the nature of the image.