Analysis, Comparison, and Assessment of Latent Fingerprint Preprocessing
Haiying Guan, Paul Y. Lee, Curtis L. Lamp, Andrew M. Dienstfrey, Mary F. Theofanos, Brian C. Stanton, Matthew Schwarz
Latent fingerprints obtained from crime scenes are rarely immediately suitable for identification purposes. Instead, most latent fingerprint images must be preprocessed to enhance the fingerprint information held within the digital image, while suppressing interference arising from noise and otherwise unwanted image features. In the following we present results of our ongoing research to assess this critical step in the forensic workflow. Previously we discussed the creation of a new database of latent fingerprint images to support such research. The new contributions of this paper are twofold. First, we augment this database by contracting a large group of trained Latent Print Examiners to provide Extended Features Set markups of the latent images. We discuss the experimental design of this study, and its execution. Next we propose metrics for measuring the increase of fingerprint information provided by latent fingerprint image preprocessing, and we present preliminary analysis of these metrics when applied to the images in our database. We consider formally defined quality scales (Good, Bad, Ugly), and minutiae identifications of latent fingerprint images before and after preprocessing. All analyses show that latent fingerprint image preprocessing results in a statistically significant increase in fingerprint information and quality.