01
Digitization
Transform archival manuscripts and cipher materials into structured digital research resources.
Research project · 2024–2027
Digitization, analysis, processing, and deciphering historical encrypted documents
An interdisciplinary research project in historical cryptography investigating encrypted military and political information preserved in aristocratic family archives of Central Europe, with a particular focus on the territory of today’s Slovakia.
The project
The project establishes a research base for historical cryptography of aristocratic families of Central Europe, focusing on the territory of present-day Slovakia. Its central objective is the digitization, deciphering, processing, and contextual interpretation of manuscripts that protected militarily and politically significant information.
We focus on three archival contexts: the Esterházy family archive from the reign of Maria Theresa; the Pálffy-Daun family archive, connected with Wirich Philipp von Daun, Field Marshal of the Imperial Army; and the Amade-Üchtritz family archive, associated with personalities representing the Kingdom of Saxony at the Viennese court.
The deciphering, processing, and description of these manuscripts contributes to the preservation and interpretation of cultural heritage in Slovakia and across Central Europe.
02
Analysis & processing
Study document structure, cipher systems, historical context, and computational representations.
03
Deciphering
Combine historical knowledge, cryptanalysis, and modern computational methods to recover hidden information.
Research team
A collaboration between researchers in cryptography, computer science, history, and archival studies.
Slovak University of Technology in Bratislava
Ing. Eugen Antal, PhD. CoordinatorORCID 0000-0002-9685-6051
Ing. Pavol Marák, PhD.ORCID 0000-0002-0737-473X
prof. Ing. Pavol Zajac, PhD.ORCID 0000-0003-1909-9453
prof. RNDr. Otokar Grošek, PhD. ORCID 0000-0002-3701-3468
Mgr. Ing. Matúš Jókay, PhD.
Ing. Stanislav Marochok
Slovak Academy of Sciences
PhDr. Lengyelová Tünde, CSc. Coordinator ORCID 0000-0001-9850-7755
Mgr. Duchoňová Diana, PhD. ORCID 0000-0002-7972-1745
PhDr. Dušan Kováč, DrSc.
Publications
Project-related publications supplied for this project page, arranged from newest to oldest. DOI links are included where available.
2026
MAROCHOK, Stanislav – PÁLENÍK, Ondrej. Synthetic Data Augmentation for Hierarchical Object Detection in Historical Handwritten Substitution Cipher Keys.
ANTAL, Eugen – ZAJAC, Pavol. HCPortal: Ten Years of Development.
MAROCHOK, Stanislav – BALOGH, Michal. Hierarchical Object Detection in Historical Handwritten Substitution Cipher Keys Using YOLOv11.
ANTAL, Eugen – MÍRKA, Jakub – KOVÁČ, Dušan. Development of obfuscation techniques in Vienna during the early modern era.
KRAJČOVIČ, Jozef – ANTAL, Eugen. The Attempt to Burn Down the LEV Printing House in Ružomberok.
2025
ANTAL, Eugen – ZAJAC, Pavol – PEKAREKOVÁ, Sabina Daniela. Solving sparse MRHS systems with genetic algorithms.
KRAJČOVIČ, Jozef – ANTAL, Eugen. Overview of Ciphers Used by the Czechoslovak “Maffie”.
MIKULEC, Ján – ANTAL, Eugen. Implementácia šifrovacieho stroja Condenser PBJ.
2024
ANTAL, Eugen – REUVERS, Paul – ZAJAC, Pavol. The Condenser PBJ cipher machine.
ANTAL, Eugen – ZAJAC, Pavol. Can Artificial Intelligence Solve the Mysterious Anagram From the Church of the Poor Clares in Bratislava?
ANTAL, Eugen – PEKAREKOVÁ, Sabina Daniela – ZAJAC, Pavol. On solving sparse MRHS systems with evolutionary algorithms.
MIKUŠ, Filip – MARÁK, Pavol – ANTAL, Eugen. Detekcia symbolov a transkripcia historických šifrovaných rukopisov pomocou umelej inteligencie.
SMIČÍK, Miloslav – ZAJAC, Pavol. Using MRHS solver for decoding problem.