Tokyo's Digital Archives Are Full of Duplicate Images — Officials and Experts Want That Fixed Before the Problem Gets Worse

Tokyo's public institutions are sitting on a growing problem: thousands of duplicate and mislabelled digital images clogging municipal databases, slowing document processing and, in some cases, causing errors in official records. Technology officers inside the Tokyo Metropolitan Government have been pressing since at least early 2026 for a coordinated duplicate-image replacement policy — and the pressure is now becoming difficult to ignore.

The issue has sharpened because of timing. The metropolitan government's Digital Service Bureau, headquartered in Nishi-Shinjuku, is midway through a sweeping records digitalisation drive that was accelerated after the national government set a 2025 administrative digitalisation target under the Digital Agency's reforms. With millions of scanned documents, property photographs, welfare records and infrastructure inspection images flowing into centralised servers, the volume of redundant files has compounded faster than anticipated.

Why Image Duplication Has Become a Governance Problem

Duplicate images are not merely a storage inconvenience. In the context of Tokyo's ward-level government — where 23 special wards each maintain their own administrative systems — identical images filed under different case numbers have led to processing delays in welfare and housing applications. Shibuya Ward and Koto Ward have both been cited internally as examples where image management protocols need tightening, according to documents circulating among IT contractors working on the city's unified records platform.

Experts in digital records management have argued publicly that the root cause is structural. Japan's public sector digitalisation has historically layered new systems on top of legacy filing practices rather than rebuilding workflows from scratch. The result is that an inspection photograph taken in, say, Kiyosumi-Shirakawa might be uploaded three times across three separate departmental folders with three different file names — none of them flagged as redundant by the current software.

The Tokyo Metropolitan Archives, located in Hongo, Bunkyo Ward, manages more than 1.4 million administrative documents in digital form as of its most recent published annual report. Staff there have been piloting AI-assisted image-matching tools since October 2025, attempting to identify duplicates before they migrate into long-term storage. The pilot covers roughly 80,000 image files, a fraction of the total holdings.

What Officials and Technical Experts Are Calling For

The Digital Service Bureau has not yet issued a binding citywide directive on duplicate-image replacement, but the policy conversation has moved well beyond informal discussion. Specialists in municipal IT governance have called for a three-step framework: automated detection using perceptual hashing technology, a mandatory human review stage for flagged files, and a standardised replacement protocol that preserves audit trails when a duplicate image is retired from a database.

The National Institute of Informatics, based in Hitotsubashi, Chiyoda Ward, has published research relevant to this problem, including work on large-scale image deduplication in institutional archives. That research, updated in a 2025 paper, estimated that duplicate files can account for between 15 and 30 percent of total image storage volume in organisations undergoing rapid digitalisation — a range that, if applied to Tokyo's municipal holdings, would represent a significant and costly inefficiency.

Cost is part of the argument. Cloud storage fees for Tokyo's digitalisation programme are not trivial. Budget documents submitted to the metropolitan assembly in March 2026 allocated approximately ¥4.7 billion to digital infrastructure for the fiscal year — a figure that makes the case for deduplication as a cost-control measure, not just a technical nicety.

Observers of Tokyo's governance process note that the city tends to move through pilot programmes before issuing system-wide mandates, a pattern consistent with how the metropolitan government handled the rollout of its e-application system for resident services. If that model holds, a formal duplicate-image replacement guideline could reach ward governments by the end of fiscal 2026, which closes in March 2027. Ward IT managers have been advised informally to begin auditing their own image repositories now, rather than waiting for a top-down directive. Those who start early will have a cleaner baseline when any mandatory policy eventually lands.