Resolution and Size of Measured Area Influences on the Short-and Long-Term Aging of Latent Fingerprint Traces Using the Binary Pixel Feature and a High-Resolution Non-Invasive Chromatic White Light (CWL) Sensor

Determining the age of a latent fingerprint trace found at a crime scene is an unresolved research issue since decades. Adopting a high-resolution, optical, non-invasive measurement device (FRT-MicroProf 200 CWL 600) from the area of surface quality measure-ment and combining it with pattern-recognition tech-niques might allow us to finally solve this important research challenge. Based on previous work, we evaluate the promising binary pixel aging feature, investigating its dependency on the resolution ( 1, 2, 3, 5, 10 mu m) and the size of the measured area (3x3, 5x5, 10x10mm) for the aging of 16 different latent fingerprint traces, in respect to the short-term aging (< 4days) and the long-term aging (> 4days), leading to a total of 739 scans. Our first experiments show a promising tendency that the binary pixel feature has a very characteristic, logarithmic aging curve for all tested resolutions and sizes of measured area for the short-and long-term aging.