The investigation of a relative contrast index model for fingerprint quantification

Abstract

The quantification of fingerprint contrast is a relatively new concept in fingerprint enhancement research. It has emerged as a mode of fingerprint assessment to reduce the potential biased of visual qualitative assessment. Subjective qualitative methods that are currently reported in the literature include; side-by-side assessment, assigning a score to a treatment based on visible criteria and stating observed results without presenting supporting validation. These qualitative methods often do not state clearly the visual assessment parameters and produce a degree of ambiguity when defining the enhancement results. The relative contrast index model was constructed to empirically quantify the difference in contrast between fingerprint ridges and valleys, using measurements gained from a microspectrophotometer. This paper seeks to further investigate this recent research and test the model using three different microspectrophotometers. Data from these separate sources will determine whether the theoretical aspects of the model would pragmatically produce reliable and repeatable results across a range of microspectrophotometers found in forensic laboratories.