Tokyo's Digital Archives Are Riddled With Duplicate Images — Officials and Experts Are Finally Talking About the Cost

Tokyo's municipal digital infrastructure is carrying tens of millions of duplicate image files across government-operated databases, and the officials and technologists responsible for cleaning up the mess are now saying publicly what they have long discussed in private: the problem is expensive, it is getting worse, and fixing it requires more than a software patch.

The issue has sharpened in 2026 because the Tokyo Metropolitan Government's ongoing DX — digital transformation — push, anchored in the Koike administration's broader Smart Tokyo initiative, has forced a systematic audit of how ward offices and city agencies store visual assets. That audit is surfacing uncomfortable numbers. When multiple departments digitise the same historical photograph, the same promotional image for a tourism campaign, or the same infrastructure inspection photo without a shared asset management system, those files multiply silently across servers.

Why now? The Metropolitan Government has been migrating legacy systems ahead of a planned 2027 consolidation of administrative IT infrastructure. Engineers working on that migration — at agencies including the Bureau of General Affairs in Shinjuku and the Tokyo Metropolitan Institute of Technology in Hachioji — have flagged duplicate image volumes as a primary driver of ballooning cloud storage contracts. Storage costs that compound month-on-month on platforms billed in US dollars hit harder when the yen remains historically weak against the dollar, a pressure point that has run through the city's procurement budgets since 2022.

What the Specialists Are Saying

Technology consultants working with Minato and Shibuya ward offices on document digitalisation projects have described the duplicate image problem in consistent terms: most organisations accumulate duplicates not through carelessness but through siloed workflows. A tourism image uploaded by the Tokyo Convention & Visitors Bureau, for instance, may also sit on the servers of the Bureau of Industrial and Labor Affairs, the relevant ward office, and three separate contractor systems — each copy legitimate in context, each one costing money and slowing search retrieval.

Experts in digital asset management point to perceptual hashing — an algorithmic technique that identifies visually identical or near-identical images regardless of file name or minor compression differences — as the most practical first-pass solution. Unlike exact-match deduplication, perceptual hashing catches the same photograph saved as both a JPEG and a PNG, or resized to different pixel dimensions across departments. Several Japanese government bodies, including agencies within the Ministry of Internal Affairs and Communications, have referenced this approach in recent procurement guidelines, though implementation at the metropolitan level remains uneven.

The Tokyo Metropolitan Government's own Digital Services Bureau, established in April 2021, has made workflow standardisation a stated goal. But coordinating image asset policy across 23 special wards — each with administrative autonomy — plus numerous metropolitan-level agencies is a governance challenge as much as a technical one. Ward offices in Kōtō and Nerima, for example, operate their own citizen-facing portals with separately managed image libraries that have no automatic synchronisation with central metropolitan systems.

Scale and What Comes Next

There are no official published figures yet on the total volume of duplicate files across metropolitan systems, and the Bureau of General Affairs has not released the results of its ongoing audit. However, technology firms specialising in Japanese public-sector IT have noted publicly — in presentations at events including the annual GovTech Summit held at Tokyo Big Sight in Ariake — that municipal governments in Japan typically discover duplication rates of between 20 and 40 percent in unmanaged image repositories. Applying even the lower end of that range to a city of Tokyo's administrative scale suggests the redundant data footprint is substantial.

Practical pressure is building from multiple directions. The inbound tourism surge of 2025 and 2026 has pushed the metropolitan government and its partner agencies to produce and publish more visual content than at any previous point — promotional material for neighbourhoods from Yanaka to Odaiba, infrastructure imagery for accessibility guides, and event photography from venues including Tokyo Dome and Ryōgoku Kokugikan. More images produced means more opportunities for duplication if common asset standards are not enforced from the point of creation.

Officials and consultants tracking this issue say the most actionable near-term step is establishing a single controlled vocabulary and centralised digital asset management platform shared across metropolitan bureaus — a recommendation that has appeared in internal working group documents but has not yet been translated into a funded project with a delivery date. Until that changes, the duplicates will keep accumulating.