Enhancement of digital images for extracting geometrical features of material grains in nanoscale materials research

This article addresses the issue of extracting geometrical features of material grains from raw digital images obtained by commercial microscopes used in nanoscale materials research. Algebraic numerical procedures are developed to estimate geometrical quantities such as grain size distribution, shape orientation, and shape irregularity after a sequence of preprocessing steps applied to raw images. Testing results on a real image are presented following the description of the algorithms.