Tokyo Leads Asia in Scrubbing Duplicate Images From Public Records, But Still Trails Amsterdam and Seoul

Tokyo's Bureau of General Affairs has been quietly working since April 2026 to eliminate tens of thousands of duplicate images clogging the city's centralised digital asset repositories — a problem that officials say has worsened sharply since inbound visitor numbers surged past 20 million annually into the metropolitan area. The cleanup effort, centred on the bureau's Shinjuku-based document management centre off Okubo-dori, targets everything from redundant cadastral survey photographs duplicated across ward offices to tourism promotion images filed multiple times under different metadata tags by separate city departments.

The timing matters. Tokyo is mid-cycle on a broader digital transformation push — the metropolitan government's DX promotion plan, extended through fiscal year 2027, has pinned data hygiene as a prerequisite for any meaningful AI-assisted public services rollout. Duplicate image files are not a cosmetic problem; they slow retrieval systems, inflate cloud storage costs, and generate errors when automated tools confuse similar-but-distinct photographs of the same location taken months apart. With the yen weakened against the dollar and cloud storage priced in dollars by major vendors, every redundant gigabyte carries a real fiscal sting.

Ward Offices at the Front Line

The duplication problem is most acute at the ward level. Minato City Ward Office and Shibuya City Ward Office — both of which manage large volumes of urban planning imagery, event documentation, and tourism-related assets — have independently commissioned deduplication audits in 2025 and 2026 respectively. Shibuya's audit, conducted under its Smart City Promotion Division, identified a backlog of image assets where an estimated 30 percent of stored files were functional duplicates or near-duplicates generated by different staff uploading the same source photograph through separate systems. Minato Ward's review flagged similar structural issues tied to the ward's extensive redevelopment documentation for the Toranomon and Azabudai districts.

The city is piloting perceptual hashing software — a technique that generates a compact fingerprint for each image and flags pairs that score above a similarity threshold — across three departments, with the Tokyo Metropolitan Government's Information Systems Division coordinating the rollout. The pilot runs through September 2026 before a decision on metropolitan-wide deployment. Storage rationalisation is projected to reduce image-related cloud expenditure by roughly 15 percent across participating departments, according to the division's internal planning documents cited in a Tokyo Metropolitan Assembly budget committee session in May 2026.

How Tokyo Stacks Up Globally

Tokyo is not alone in wrestling with this, but it is behind some peers. Amsterdam's municipal archive — the Stadsarchief Amsterdam — completed a full deduplication sweep of its digitised image holdings in 2023, deploying open-source tooling across roughly 900,000 photographic records and publicly documenting its methodology. Seoul's Smart City data governance framework, updated in 2024, mandated deduplication checks as a condition of procurement for any new digital asset management system used by city agencies, effectively baking the fix into vendor contracts rather than treating it as a cleanup afterthought.

London's situation more closely resembles Tokyo's: the Greater London Authority and its functional bodies have inconsistent standards across boroughs, with Transport for London running its own asset management protocols largely independent of borough-level systems. That fragmentation is familiar to anyone who has tried to reconcile records between, say, Chiyoda Ward and the Tokyo Metropolitan Police Department's public affairs imagery files.

Singapore's Government Technology Agency has gone furthest, integrating image deduplication into its Whole-of-Government platform so that any file uploaded by a ministry is automatically checked against a central hash registry before it is saved. Tokyo has nothing analogous yet, though the DX promotion plan does reference a "single source of truth" document standard as a long-term objective.

For residents and businesses dealing with Tokyo's ward offices — particularly developers filing planning applications in high-activity zones like Shibuya or Toranomon — the practical upshot is straightforward: digital submissions that include photography should use standardised metadata and avoid resubmitting image files that have already been lodged as part of earlier applications. The Bureau of General Affairs is expected to publish updated submission guidelines by October 2026, ahead of the next fiscal year's planning cycle. Departments still running legacy Windows-based document management systems are on a mandatory migration list by March 2027 — the point at which deduplication tooling is scheduled to become operational city-wide.