INVESTIGATIONS OF IMAGE-CONTRAST SPACE DEFINED BY VARIATIONS ON HISTOGRAM EQUALIZATION

This paper describes how a family of images of varying levels of contrast can be efficiently calculated and displayed. We show that a contrast space defined in terms of histogram equalization can be specified in terms of two parameters: region size and histogram blurring level. Based on these observations, we describe one exact algorithm and two efficient algorithms for computing sequences of images within this contrast space. These precomputed images can be displayed and interactively explored to examine image features of interest. By working with a family of contrast enhanced images the difficult task of selecting the single level of contrast enhancement appropriate for a particular image is avoided, increasing the usefulness of low contrast images. © 1992.