Melbourne's Libraries and Archives Are Quietly Winning the War on Duplicate Digital Images — Here's How They Compare to London and Toronto

Melbourne's State Library Victoria completed a two-year audit of its digitised photographic holdings in June 2026, identifying more than 340,000 duplicate image files that had accumulated across its servers since large-scale digitisation began in the early 2010s. The finding, confirmed in the library's internal collections management documentation, has renewed debate about how cultural institutions handle what archivists call the "duplicate image problem" — redundant scans that consume storage, distort collection counts and complicate public search results.

The timing matters. Storage costs for large cultural institutions have risen sharply, and public funding for digital infrastructure is under scrutiny at both state and federal levels. The Victorian government's Creative State 2025–2028 strategy explicitly ties ongoing investment in cultural institutions to measurable improvements in digital asset management. Across Swanston Street at the Melbourne Museum, a separate project to reconcile duplicate images within Museums Victoria's online catalogue has been running since February 2026, targeting holdings across natural history, Indigenous cultural material and post-war immigration photography.

What Melbourne Is Actually Doing

State Library Victoria is using a combination of perceptual hashing software — technology that generates a fingerprint for each image regardless of file name or format — and manual curatorial review to triage its backlog. Perceptual hashing can detect near-identical images even when one has been cropped or had its contrast adjusted, which catches a category of duplicates that simple checksum matching misses entirely. The library's digital preservation team, based at its La Trobe Street building in the CBD, has set a target of resolving the bulk of confirmed duplicates by the end of the 2026 calendar year.

The City of Melbourne's own digital archive, managed through the Melbourne City Archives on Little Collins Street, took a different route. Rather than retrofitting a deduplication layer onto an existing system, archivists migrated the entire photographic collection to a new digital asset management platform in late 2024, building deduplication protocols into the ingest workflow from the start. That means every new image upload is checked against existing holdings before it enters the collection — preventing the problem from re-accumulating rather than just cleaning up what already exists.

How Melbourne Stacks Up Against London and Toronto

The British Library in London completed a comparable deduplication exercise across its newspaper digitisation program in 2023, working through an estimated 1.2 million flagged duplicate image files generated during the British Newspaper Archive project. The scale dwarfs Melbourne's current challenge, but the British Library had a structural advantage: its digitisation contracts after 2018 required vendors to submit deduplication reports as part of delivery, shifting responsibility upstream. Melbourne institutions are only now beginning to embed similar contractual requirements.

Toronto Public Library, which manages one of the largest municipally held photograph collections in North America at its Spadina Road facility, adopted an open-source perceptual hashing pipeline in 2022. According to documentation published by the library's digital services team, the system reduced active storage consumption for photographic holdings by 18 per cent within 12 months of deployment. Melbourne's Museums Victoria has cited the Toronto model in its own project planning materials, though its implementation remains at an earlier stage.

Where Melbourne appears to have an edge is in cross-institutional coordination. A working group convened by the Public Record Office Victoria has brought State Library Victoria, Museums Victoria and the Melbourne City Archives into a shared conversation about common metadata standards — a step that London and Toronto have each attempted with uneven results, partly because their institutional landscapes are more fragmented across government tiers.

For members of the public who search digitised collections, the practical effect of unresolved duplicates is search results cluttered with multiple versions of the same photograph, often with conflicting catalogue descriptions. Researchers using Trove, the National Library of Australia's aggregation platform, have long noted this problem with Victorian holdings in particular. Once deduplication projects at State Library Victoria and Museums Victoria feed cleaner records back into Trove — a process expected to begin in early 2027 — the improvement to search quality should be tangible. The real test will be whether the ingest-level controls now being written into procurement contracts actually hold when the next large digitisation tender is awarded.