The Hidden Numbers Behind Melbourne's Duplicate Image Problem: What the Data Reveals

Victorian public institutions collectively manage tens of millions of digital image files, and a growing body of internal audits suggests that anywhere between 30 and 45 per cent of those files are duplicates — identical or near-identical copies stored redundantly across multiple servers, drives and cloud platforms. The problem is not new, but the cost attached to it is getting harder to ignore.

The issue has sharpened this year because the Allan government's digital infrastructure review, which began in earnest in early 2026, has pushed agencies to account for storage expenditure in granular detail for the first time. Cloud storage pricing — typically billed per gigabyte per month — means duplicate files are not just a tidiness problem. They are a recurring line item on agency budgets, month after month.

What the Numbers Actually Look Like

Enterprise cloud storage on Australian-hosted platforms currently runs between $0.023 and $0.028 per gigabyte per month for standard-tier access, according to published pricing schedules from major providers operating under Australian data sovereignty rules. A single high-resolution image from a modern DSLR camera can sit between 25 and 50 megabytes. Scale that across, say, the City of Melbourne's archive of public event photography — which spans festivals from Federation Square to Birrarung Marr and covers roughly two decades — and the redundancy problem becomes financially material very quickly.

The State Library Victoria, based on Swanston Street in the CBD, manages one of the largest public digital image collections in the southern hemisphere. Its digitisation program, which accelerated under a federal funding commitment in 2022, has produced collections running into hundreds of terabytes. Librarians and archivists familiar with large-scale digitisation projects say duplicate ingestion — where the same physical item is scanned more than once, or where files are copied across departments without a deduplication step — is a near-universal problem at that scale. The library has not published a specific duplication rate for its holdings.

The Victorian Collaborative Library Service, which coordinates shared digital infrastructure across more than 250 public library branches statewide, flagged duplicate asset management as a priority in its 2025-26 operational planning cycle. The cost of storage redundancy across the network, while not publicly itemised, is understood to be a recurring agenda item at quarterly infrastructure meetings.

Why Deduplication Is Harder Than It Sounds

Removing duplicate images from a large institutional archive is not simply a matter of running a piece of software. Image deduplication tools rely on hash-matching for exact duplicates, but near-duplicate detection — where an image has been slightly cropped, resized or colour-corrected — requires more sophisticated machine-learning approaches that carry their own licensing and implementation costs.

Creative Victoria, the state government's arts funding and development agency based in the Melbourne Arts Precinct on Southbank, administers grant programs that regularly produce large volumes of photographic documentation. Funded projects are typically required to submit image assets as part of acquittal reporting. When those images are stored by both the applicant and the agency, duplication begins at the point of submission.

The practical maths are instructive. If a mid-sized government department holds 500,000 image files with a 35 per cent duplication rate, it is storing roughly 175,000 unnecessary files. At an average compressed size of 8 megabytes per file, that is 1.4 terabytes of redundant data. At current Australian cloud rates, that redundancy costs the department somewhere between $387 and $470 per year — modest in isolation, but multiplied across dozens of agencies and councils, the statewide figure climbs into the hundreds of thousands of dollars annually.

For institutions looking to act, the practical steps are well-established: conduct a full asset audit using hash-based deduplication tools as a first pass, establish a single-source-of-truth repository with access controls, and build deduplication checks into ingestion workflows before files are committed to storage. Several Melbourne-based digital asset management firms, concentrated around the technology and creative precincts in Cremorne and Fitzroy, offer managed audit services for institutional clients. The cost of a one-time audit is typically recovered within 18 months through storage savings alone — a calculation that is becoming harder for budget-conscious Victorian agency heads to set aside.