Barcelona's Digital Archives Grapple With Duplicate Image Problem: What Officials, Experts and Key Groups Are Saying

Barcelona's municipal digital archive has a problem it can no longer quietly ignore. Across platforms maintained by the Ajuntament de Barcelona and the Institut de Cultura de Barcelona (ICUB), tens of thousands of duplicate images — scanned photographs, urban planning renders and event documentation — are consuming server capacity, slowing public access portals and, in some cases, presenting conflicting metadata to researchers and journalists who rely on the records. The issue surfaced formally in late June 2026 when a working group convened by the Arxiu Municipal Contemporani de Barcelona, located on Carrer de Bisbe Caçador in the Gothic Quarter, flagged the duplication rate in a technical review submitted to the city's digitalisation directorate.

The timing is not incidental. Mayor Jaume Collboni's administration has committed to an expanded open-data agenda as part of the Barcelona Digital 2026 framework, and the archive's credibility is central to that plan. When the same image appears under three different catalogue numbers — with different rights designations attached to each — it creates legal ambiguity for media organisations, urban planners and academic institutions that license the material. Archivists say the problem has been building since at least 2018, when the city accelerated bulk digitisation ahead of the Superilla Barcelona programme's documentation phase.

What the Institutions Are Saying

The Arxiu Municipal itself has not issued a public statement, but the working group's internal review — portions of which have circulated among professional contacts in the library and information science community — identifies three root causes: inconsistent file-naming protocols across different municipal departments, repeated batch uploads during server migrations in 2021 and 2023, and the absence of a centralised deduplication tool with authority across all contributing bodies. The Consorci de Biblioteques de Barcelona, which manages 40 public library branches across the city, faces a parallel version of the same challenge in its shared digital catalogue.

Experts in digital preservation at the Universitat de Barcelona's Facultat de Biblioteconomia i Documentació have been vocal in professional forums about the need for hash-based deduplication — a technique that generates a unique fingerprint for each image file and automatically flags exact copies, regardless of filename. The faculty has offered to collaborate on a pilot programme, though no formal agreement with the Ajuntament has been announced. Photographic professionals at the Col·legi de Periodistes de Catalunya, on Rambla de Catalunya, have also raised the issue from a licensing standpoint, noting that duplicate records with conflicting rights information put news organisations in an uncertain legal position when republishing archival images.

The Scale of the Problem and What Comes Next

Precise figures are difficult to verify without access to the full technical audit, but the working group's review is understood to reference a duplication rate of roughly 12 to 18 percent across the contemporary archive's photographic holdings — a range that, applied to a collection running into several hundred thousand items, represents a substantial administrative burden. Each duplicate record requires manual review if the metadata diverges, and staff capacity at the Arxiu Municipal Contemporani has not expanded to match the digitisation pace.

The Barcelona Supercomputing Centre — Centre Nacional de Supercomputació, based at the Torre Girona chapel on Carrer de Jordi Girona in the university district — has developed image-recognition tools for scientific data management that archivists believe could be adapted for cultural heritage collections. Whether a formal partnership materialises before the end of 2026 depends partly on budget allocation in the city's second-half spending review, due in September.

For researchers, journalists and citizens who use the Ajuntament's open data portals daily, the practical advice from information professionals is straightforward: when pulling archival images, cross-reference catalogue numbers against the image's creation date and the originating department, since those fields are less likely to carry errors than the file-naming fields affected by the bulk uploads. The city's digitalisation directorate has indicated it plans to publish updated technical guidelines for institutional contributors before the end of the third quarter. That deadline, and what enforcement mechanism accompanies it, will be the clearest signal yet of how seriously City Hall intends to treat the problem.