Contrast enhancement and depth perception in three‐dimensional representations of differential interference contrast and confocal scanning laser microscope images

Abstract

SUMMARYA commonly used three‐dimensional reconstruction method in confocal scanning laser microscopy (CSLM) involves the generation of stereo views by stacking optical sections. Under certain conditions the resulting stereo pairs exhibit inferior quality with respect to contrast and depth perception. A method based on digital image processing is described in which the individual images are enhanced prior to reconstruction, thereby increasing the number of usable optical sections by a factor of up to five. Furthermore, we introduce a new contrast enhancement transformation based upon local statistics and a grey‐level probability density function that provides improved depth perception. Digital image processing methods map a discrete grey scale onto a continuous, unbounded interval. Inasmuch as a closed, discrete grey scale is required for computer display purposes, we present an appropriate mapping function derived from an entropy criterion.