Photo metadata fidelity: samples, hashes & reproducible tests

Download the complete evidence kit

Download verification kit ZIP · Fixture manifest & source hashes · Full results JSON · Methods & licensing README

The kit includes sources, all four outputs, an originals ZIP, writer snapshots and a verification script. Images are tiny program-generated color grids with invented author, camera and GPS fields; no real people or capture locations are included.

Per-fixture results: payloads and pixels match

Each fixture runs author/camera/GPS edits, GPS-only removal, EXIF-only removal and the all-metadata scope. The two checks compare preserved image block bytes and decoded raw pixels. Expand the final column for output downloads and before/after fields.

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Fidelity Edited",
    "make": "Fidelity Camera",
    "latitude": -33.5,
    "longitude": 151.20000000000002
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Fidelity Edited",
    "make": "Fidelity Camera",
    "latitude": -33.5,
    "longitude": 151.20000000000002
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Fidelity Edited",
    "make": "Fidelity Camera",
    "latitude": -33.5,
    "longitude": 151.20000000000002
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Fidelity Edited",
    "make": "Fidelity Camera",
    "latitude": -33.5,
    "longitude": 151.20000000000002
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Fidelity Edited",
    "make": "Fidelity Camera",
    "latitude": -33.5,
    "longitude": 151.20000000000002
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Fidelity Edited",
    "make": "Fidelity Camera",
    "latitude": -33.5,
    "longitude": 151.20000000000002
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Fidelity Edited",
    "make": "Fidelity Camera",
    "latitude": -33.5,
    "longitude": 151.20000000000002
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Fidelity Edited",
    "make": "Fidelity Camera",
    "latitude": -33.5,
    "longitude": 151.20000000000002
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Fidelity Edited",
    "make": "Fidelity Camera",
    "latitude": -33.5,
    "longitude": 151.20000000000002
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

{
  "before": {
    "artist": "Synthetic Author",
    "make": "Synthetic Camera",
    "latitude": 46.5,
    "longitude": 11.8
  },
  "after": {
    "artist": null,
    "make": null,
    "latitude": null,
    "longitude": null
  }
}

Download originals ZIP — All nine entries use STORE and extract to the source SHA-256 hashes in the manifest. Originals retain their source test metadata; edits and removal are not applied.

Reproduce locally without a download plan

1. Download and extract the complete kit. Use Node.js 22.13 or newer.
2. Run the following in the extracted directory. Installation downloads the sharp decoder dependency; verification only reads local kit files and does not upload photos.

   npm install
   npm run verify

3. Expect PASS for 36 transformations and nine byte-identical STORE originals. The script regenerates outputs and compares their bytes with the published files, rather than trusting the results JSON.
4. You can also import a source and a published output into the viewer to inspect author and GPS fields. Workspace image downloads keep their existing plan rules; evidence files here are directly available for free.

Published checks use sharp 0.35.4 / libvips 8.18.6. The kit pins sharp and prints the actual decoder versions; investigate any pixel differences on another decoder or platform separately.

What exactly is compared?

• JPEG: compressed scan bytes from the first SOS marker to EOF. PNG: image/animation and selected color chunks. WebP: compressed image, alpha, animation and ICC chunks. Classic TIFF: image strips or tiles for all pages.
• Decode using sharp separately from the metadata writer; compare raw pixels, dimensions, bit depth, page count and frame delays. The 16-bit sample is compared as ushort, without reducing to 8 bits.
• Assert expected author, camera and GPS changes. Edited author becomes Fidelity Edited; GPS-only retains author and clears coordinates; EXIF-only and all-metadata scope clear these test fields.
• The writer snapshot and JPEG/originals-ZIP functions come directly from this site version. Snapshot hashes identify the code tested; this is not third-party certification.

Coverage and limits

These are tiny reproducible synthetic tests, not a study of every camera file. Coverage includes lossy/lossless and animated WebP, LZW/Deflate TIFF, 16-bit and multipage TIFF. BigTIFF, all vendor extensions, malformed directories and large-file stress are excluded.

Fixtures have no orientation rotation and decoding uses no auto-orientation. Removing orientation from other JPEG, PNG or WebP files may change displayed rotation despite identical compressed image bytes. The app previews the first TIFF page; exported edits apply to all pages.

GPS-only removal leaves XMP/IPTC, filenames and visual location clues. The all-metadata scope retains decoding/color data and classic TIFF layout/orientation tags. This page only asserts the listed fields and offers no forensic anonymity guarantee.

For tutorial authors: how to cite

You may cite the results and methods with the fixture coverage and the description “product-authored synthetic test.” Fixture images and transformed copies are dedicated under CC0 1.0 for reuse in tutorials. Code and third-party libraries retain their own terms; see the kit README.

EXIF Studio. Metadata fidelity verification, v1 (2026-10-30). https://exifdesk.com/fidelity-verification#results

Stable citation anchors: #results · #method · #limits. To report a mismatch, include the fixture, operation and Node/decoder versions: support@exifdesk.com.

Inspect fields in the viewer → · Understand removal scopes →