  Digital image comparison and matching brings many advantages over the
traditional subjective human comparison, including speed and reproducibility.
Despite the existence of an abundance of image difference metrics, most of them
are not suited for high-resolution transmission electron microscopy (HRTEM)
images. In this work we adopt two image difference metrics not widely used for
TEM images. We compare them to subjective evaluation and to the mean squared
error in regards to their behaviour regarding image noise pollution. Finally,
the methods are applied to and tested by the task of determining precipitate
sizes of a model material.
