Abstract

Present imaging techniques, such as synthetic aperture radar and ultrasound, produce images with a dynamic range (contrast) larger than can be displayed on film or CRT. Pseudocolor could be used to increase the contrast of displayed large dynamic range images if a color scale could be found which has (1) an intuitively obvious correspondence with image intensity values (thus requiring little retraining of observers); (2) greater contrast (more distinguishable colors) than a gray scale; and (3) improved image interpretability. Color scales which satisfy the first two requirements are those which monotonically increase in brightness (or saturation) and have minimal variation in hue. Subjective evaluation of many color scales by human observers determined that black-white-red and black-white-blue scales were preferred. A black-white-red (or black-white-blue) scale begins at black for low image values, increases in intensity to white, and then increases in saturation to red (or blue).

© 1989 Optical Society of America