Before
The fixture contains one declared signal family.
The inspector must identify the supported C2PA/JUMBF, XMP, EXIF/GPS, PNG text or WebP metadata structure.
Open test evidence · version 2026.07.19
AI Info cleaning claims should survive a before-and-after test.
This lab records the exact file structures the current browser engine checks, what disappears after Safe Clean, and whether the encoded visual payload covered by the verifier still matches. Every result below uses a deterministic synthetic fixture—not a claim about every editor or Instagram decision.
Measured July 19, 2026 · seven passing cases · machine-readable JSON available
Current result
7 / 7 stated conformance cases pass.
JPEG, PNG and WebP cases cover recognized provenance containers, descriptive or private metadata, prompt-like PNG text and payload-preservation checks. Unknown structures are preserved instead of guessed at.
Fixture-level evidence
Seven narrow assertions, not one universal promise.
- JPEG C2PA/JUMBFRecognized APP11 provenance data is removed; unrelated APP11 data is preserved.
- JPEG XMPStandard and linked Extended XMP are removed in Safe Clean.
- JPEG EXIF/GPSPrivate EXIF and GPS fields are removed while rendering-sensitive orientation is handled conservatively.
- PNG prompt textSupported tEXt, iTXt and zTXt metadata chunks are removed without rewriting IDAT image data.
- PNG XMP/provenanceSupported XMP and recognized provenance chunks are removed; rendering chunks remain.
- WebP EXIF/XMPEXIF and XMP chunks are removed while VP8, VP8L, ALPH and animation payloads remain covered by verification.
- Payload guardA changed encoded image byte produces a mismatch and blocks a false “unchanged” result.
After
The declared structure is gone and the visual payload still matches.
The cleaner is re-run through the inspector; a scoped SHA-256 proof compares the encoded image payload before download.
Reproducible method
Construct → inspect → clean → re-inspect → hash.
- Construct a minimal valid JPEG, PNG or WebP byte structure with a declared synthetic metadata block.
- Confirm the public engine identifies that supported block before cleaning.
- Run Safe Clean and inspect the returned bytes again.
- Confirm the declared supported block is absent and guarded rendering data remains.
- Compare SHA-256 over JPEG scan data, PNG image-data payload, or WebP image/animation chunks.
The word “synthetic” matters: these fixtures test the byte structures, not a vendor's current export UI. A platform can also use disclosures, server history, classifiers or durable watermarks outside ordinary metadata.
Boundary
A passing file test does not promise an Instagram label outcome.
These results establish only that the stated embedded structures can be removed without changing the encoded image payload covered by the current verifier. They do not authenticate a scene, erase an invisible watermark, change pixels, undo a label already attached to a post, or guarantee reach.