A NOTE ON THE USE OF (GRAY LEVEL, LOCAL AVERAGE GRAY LEVEL) SPACE AS AN AID IN THRESHOLD SELECTION

1•~~~ ~ Various methods have been proposed for improvingthe gray level histogram of an image so as to make it easier to select thresholds for segmenting the image. u_i This note describes how (gray level, local average gray level) feature space can be used to define im-proved image histograms. The approach is analogous to that in an earlier note which made use of second-c. ~ order gray level histograms ( “ cooccurrence matrices ’)~~~ ~ for similar purposes