Delhi's Duplicate Image Problem: How the Capital Stacks Up Against Mumbai, London and Seoul

Delhi's public record offices are sitting on a crisis that rarely makes front pages. Tens of thousands of duplicate photographs — submitted by residents for ration cards, voter ID enrolments, property registrations and Delhi Metro smart card applications — have clogged municipal databases managed by the Delhi government's Department of Information Technology. The backlog, which IT administrators at the Delhi Secretariat acknowledged at a public workshop in March 2026, has slowed identity verification processing times at some district offices by an estimated 30 to 40 percent compared to 2023 benchmarks, according to internal departmental assessments cited at that session.

The issue has sharpened because of timing. The Election Commission of India launched its continuous voter roll revision drive in early 2026, pushing fresh enrolment across all 70 Delhi assembly constituencies. Simultaneously, the Aadhaar-linked DigiLocker integration project — rolled out across Delhi government services by the National e-Governance Division — has surfaced thousands of cases where the same citizen photograph exists under multiple document IDs. Staff at the South Delhi Municipal Corporation's Saket zonal office and the revenue department's Tis Hazari counter described to this reporter a common pattern: applicants resubmitting documents because prior uploads failed, resulting in two or three identical image files attached to a single record.

What Delhi Is — and Isn't — Doing

The Delhi State Data Centre in Dwarka, which hosts servers for multiple civic portals, began piloting a perceptual hash-based deduplication tool in January 2026. The technology, similar to systems deployed by Seoul Metropolitan Government for its resident registration database since 2022, flags visually identical or near-identical image files before they are written to permanent storage. Seoul completed a citywide clean-up of roughly 2.1 million duplicate entries in its civic ID system over 18 months, according to a 2024 report published by the Korea Institute of Public Administration. Delhi's pilot, by contrast, covers only three departments and has not yet been extended across the full stack of portals under the Delhi e-District platform.

London's Government Digital Service set a relevant precedent when it mandated single-instance image storage across GOV.UK verify-linked services in 2021, reducing storage costs by roughly 18 percent across participating agencies, per figures published in the GDS annual report that year. Mumbai's Brihanmumbai Municipal Corporation began a comparable deduplication audit of its property tax portal in February 2026, hiring a Pune-based technical consultancy to run the process — a step Delhi has not yet formally tendered. The contrast matters because Mumbai and Delhi face broadly similar data volumes, given comparable population sizes and the density of government service interactions per resident.

Old Delhi presents a particular complication. Heritage documentation projects run by organisations such as INTACH — the Indian National Trust for Art and Cultural Heritage, which maintains offices in Nizamuddin East — have digitised thousands of archival photographs of buildings in areas like Chandni Chowk and Ballimaran. Many of those scanned images now exist across multiple formats and resolutions on servers shared with the Archaeological Survey of India. No unified deduplication protocol currently governs that overlap, leaving heritage archivists to manage it manually.

What Residents and Agencies Should Expect Next

The Delhi government's IT department has indicated, in budget documents tabled before the Delhi Assembly in February 2026, that ₹4.2 crore has been allocated for database optimisation in the 2026–27 financial year. Whether that figure covers deduplication infrastructure specifically, or broader data centre upgrades, was not specified in the published budget line. IT officials at the Secretariat did not respond to requests for clarification before this article went to press.

For residents, the practical consequence is straightforward: submitting a fresh photograph for any Delhi government service — rather than reusing a scan of a scan — significantly reduces the chance of a duplicate flag holding up a file. The e-District helpline, reachable at 1076, can advise on document resubmission procedures. Applicants at high-volume centres like the Dwarka Sub-City District Office and the Rohini revenue circle have been advised to use the DigiLocker direct-upload pathway rather than email attachments, which have historically generated the most duplication. The deduplication pilot's results are expected to be reviewed by the State Data Centre's oversight committee in September 2026.