The human visual recognition ability for incomplete letters

The human vision system has high-level recognition abilities and can efficiently and accurately identify an object based on object parts. In the present study, a letter recognition experiment was designed to evaluate recognition of incomplete objects by humans. Five subjects were asked to identify partially erased English letters displayed for short time periods. We found that features and correlations between features significantly influence letter identification. An algorithm based on information entropy is proposed to quantitatively evaluate the importance of letter features and the similarities between letters.