Fingerprint image enhancement by differential hysteresis processing.

Area of Science:

• Forensic Science
• Digital Image Processing
• Biometrics

Background:

• Defective fingerprints, often blurred or illegible due to poor collection, pose significant challenges in identification and comparison.
• Current methods struggle with severely degraded fingerprint images, limiting their forensic value.

Purpose of the Study:

• To develop and evaluate a novel digital image processing technique for enhancing defective fingerprint images.
• To improve the clarity and detail of low-quality fingerprints for better dactyloscopy analysis.

Main Methods:

• Application of spatial domain filters to fingerprint images.
• Utilizing a specific technique called differential hysteresis processing (DHP) for image enhancement.
• Testing the method on various degraded fingerprint samples.

Main Results:

• The applied filtering methods, including DHP, significantly improved the quality of defective fingerprint images.
• Hidden ridge details, crucial for identification, were successfully uncovered in previously illegible prints.
• The enhancement technique proved effective across a range of image degradation levels.

Conclusions:

• The developed digital image processing method is effective in enhancing defective fingerprints for forensic identification.
• This technique offers a valuable tool for dactyloscopy, particularly in cases with poor-quality evidence.
• Results were validated by experts from Policia Federal Argentina and the EAAF, confirming its practical utility.