Prague's Battle Over Duplicate and Degraded Images in Public Records: What Officials and Experts Are Saying

Prague's city administration is under growing pressure to address a sprawling problem inside its own digital infrastructure: tens of thousands of duplicate, degraded and misattributed images embedded across municipal planning documents, heritage registers and public communication databases. Specialists working with the Institute of Planning and Development — known by its Czech acronym IPR Praha — say the issue has quietly worsened since a 2023 digitisation drive pushed large volumes of analogue archive material onto city-managed servers without adequate quality controls.

The timing matters. Prague is mid-way through an ambitious urban renewal programme covering districts from Smíchov to Karlín, and planning documentation underpins everything from construction permits to heritage protection orders. When the same photograph appears under two different property references, or when a degraded scan is used to verify a listed façade on Náměstí Míru, the consequences stretch well beyond bureaucratic inconvenience. Incorrect visual records can delay permits, trigger legal disputes and, in the worst cases, result in protected architectural features being overlooked during renovation.

What the Specialists Are Saying

Experts at IPR Praha have been vocal about the need for a systematic deduplication protocol since at least early 2025. The institute, based in Vyšehrad at Antala Staška 2, oversees spatial planning data for the entire city and has identified image quality as a recurring bottleneck in its workflow reviews. Archivists there have described the current situation as one where a single building on Wenceslas Square may appear under four or five distinct file entries, each carrying a slightly different resolution or crop, none of them formally flagged as redundant.

At Charles University's Faculty of Arts, researchers working on the UrbanData Prague project — a collaboration with the National Technical Library on Technická street in Dejvice — have been developing automated tools to cross-reference visual records against geo-tagged cadastral data. The project, which received a European Regional Development Fund grant in 2024, has so far catalogued more than 40,000 image files across three municipal databases. Preliminary findings suggest roughly 18 percent of those files contain either exact duplicates or near-identical copies that serve no independent archival purpose.

City councillor portfolios covering digitisation have pointed to the need for clear replacement standards — specifically, guidance on which image version should be retained when duplicates are found, and who carries institutional responsibility for signing off on removals. Without that framework, database managers at individual district offices have been making ad hoc decisions, producing inconsistency across Prague's 22 administrative districts.

Practical Steps and What Comes Next

IPR Praha is expected to publish a formal methodology document by the end of the third quarter of 2026. That document, according to materials circulated ahead of a June planning committee session at the New Town Hall on Mariánské náměstí, would set minimum resolution thresholds for retained images — likely 300 DPI for heritage records — and establish a centralised review process managed through the city's Geoportal platform.

The Prague 1 and Prague 2 district offices, which between them hold visual records for some of the city's most densely documented historic streetscapes, are being watched closely. Both districts have independently begun audits of their image holdings, though neither has announced a completion date or a budget line for the work.

For residents and businesses navigating the planning system, the practical advice from urban consultants familiar with the process is straightforward: when submitting permit applications in districts undergoing active redevelopment — Holešovice and Žižkov chief among them right now — attach independently sourced, high-resolution photographs of affected structures rather than relying on images pulled from the city's own registers. That extra step reduces the risk that a duplicate or degraded official image creates complications during the review process.

The broader question of how Prague funds a proper system-wide image audit remains unresolved. IPR Praha's annual operational budget, as published in the city's 2026 financial plan, sits at approximately 320 million Czech crowns — a figure that covers the institute's full research, planning and publication remit, leaving limited room for large-scale data remediation without additional allocation from the City Council.