 For example, the Avante Vote-Trakker simply counts the number of dark and light pixels in each marking area to determine if the mark counts as a vote.More sophisticated mark recognition algorithms are sensitive to the shape of the mark as well as the total overall darkness, as illustrated by the ES&S Model 100, introduced in the mid 1990s.An electronic ballot marker (EBM) or ballot marking device (BMD) is a device that can aid voters in marking paper ballots.