Fingerprint image scale estimation for forensic identification systems

Oblak, Tim (author), Videnović, Jovana (author), Kupinić, Haris (author), Štruc, Vitomir (author), Peer, Peter (author), Emeršič, Žiga (author)

The large majority of modern software solutions intended for fingermark processing in a forensic context is heavily dependant on the correct image scaling. Fingermark images captured with digital cameras at a crime scene require the use of physical rulers or labels. While the resolution of a fingermark image can be calibrated manually by a forensic examiner in a lab, we propose an automated approach, which could be integrated directly into existing identification systems and would eliminate the need for human intervention. Our approach consists of a CNN regressor, which directly predicts the PPI of stochastically-sampled local patches based on the friction ridge information contained within. In a range of PPI between 500 and 1500, our method achieves a mean average error of around 24 PPI for fingerprint and fingermark images.

• Language: English
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FRI - Faculty of Computer and Information Science ; FE - Faculty of Electrical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2025
• Number of pages: Str. 1-14
• Numbering: Vol. 20, iss. 2, art. 7031
• PID: 20.500.12556/RUL-171522
• UDC: 004.93:57.087.1
• ISSN on article: 1841-9836
• DOI: 10.15837/ijccc.2025.2.7031
• COBISS.SI-ID: 227942403
• Publication date in RUL: 28.08.2025

Record is a part of a journal

• Title: International Journal of Computers, Communications & Control
• Shortened title: Int. J. Comput. Commun. Control
• Publisher: Editura Universitæaţii Agora
• ISSN: 1841-9836
• COBISS.SI-ID: 28392999

Licences

• License: CC BY-NC 4.0, Creative Commons Attribution-NonCommercial 4.0 International
• Link: http://creativecommons.org/licenses/by-nc/4.0/
• Description: A creative commons license that bans commercial use, but the users don’t have to license their derivative works on the same terms.

Secondary language

• Language: Slovenian
• Keywords: prstni odtis, prstna sled, merilo slike, napoved ppi, forenzika, fingerprint, fingermark, image scale, ppi prediction, forensics

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P2-0250-2018
• Name: Metrologija in biometrični sistemi

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P2-0214-2019
• Name: Računalniški vid