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Jun 28, 2026

AtoM Heratio — Full Embedded Metadata

Overview

AtoM Heratio captures and surfaces the complete embedded technical metadata of photographic and image assets — the entire EXIF, IPTC, XMP, MakerNotes, ICC profile, GPS, Composite and File/System tag set produced by ExifTool — rather than a curated subset. This gives archivists, cataloguers and digital-preservation staff full visibility of the technical provenance of every image, while protecting sensitive location data on public-facing surfaces.

Key Features

  • Complete capture. Every metadata group ExifTool can read is stored verbatim on the master digital object (exiftool -json -a -G1 -struct -u), alongside the existing curated descriptive fields.
  • Grouped, searchable display. A "Full embedded metadata" panel on the Digital Asset Management page presents all tags grouped by ExifTool group, with an instant client-side filter and a per-group tag count.
  • Location (GPS) protection. Coordinates and location-shaped tags are automatically withheld from non-administrators and from public API/IIIF output, while the full set is retained internally and for preservation. A clear notice indicates when hidden location data exists.
  • Automatic on upload. New image uploads are captured transparently as part of the existing metadata-extraction step; capture is best-effort and never blocks an upload.
  • Bulk backfill. A command-line tool re-captures the full set for images already in the repository, with dry-run, force-refresh, single-object and batch-limit options.
  • Open integration. The complete set is exposed through the REST API digital-object endpoint and embedded in IIIF Presentation manifests, GPS-gated for public consumers.

Compliance & Standards

  • ExifTool tag families: EXIF/TIFF, IPTC IIM, XMP, MakerNotes, ICC, GPS, Composite.
  • POPIA / GDPR alignment — embedded location data is treated as potentially personal/sensitive information and is gated from public display by default, consistent with AtoM Heratio's privacy posture.
  • Digital preservation — the complete, unaltered technical metadata is retained as structured data and captured by the platform's database backup routine.
  • IIIF Presentation API 3.0 — full metadata surfaced as manifest metadata entries.

Technical Requirements

  • ExifTool installed on the application server (/usr/bin/exiftool).
  • AtoM Heratio with the metadata-extraction component (storage table ahg_embedded_metadata, created automatically on install or first backfill).
  • No changes to core AtoM database tables; the full set is stored in a dedicated plugin table (LONGTEXT), so there is ample capacity for large tag sets.

How It Works

Stage Behaviour
Upload The extraction handler captures the full ExifTool set and stores it on the master digital object.
Display The DAM asset page renders the set grouped, collapsible and searchable; GPS gated by role.
API GET …/digital-objects/{id}?include_embedded_metadata=1 returns embedded_metadata.full (GPS-gated).
IIIF The Presentation manifest includes the full set as grouped metadata entries (GPS-gated).
Backfill php bin/atom metadata:backfill-embedded re-captures existing masters.

Availability

Included with AtoM Heritage Group (Pty) Ltd platform deployments. For configuration and the end-user walkthrough, see the Full Embedded Metadata user guide.

The Archive and Heritage Group (Pty) Ltd