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c2pa-binding §4.8 to §4.10 and §6.4: after its three assertions a store of wai.asset.c2pa may carry wai-mark:tent64 as a C2PA soft-binding assertion naming its robustness claim, the envelope's ISCC identifier, and the Creator Assertions Working Group's identity assertions (1.3, cawg.x509.cose); a verifier may hold its anchors as trust lists in the C2PA Trust List's form, pinned by the SHA-256 of their bytes. The algorithm-list entries for tent64 and band64 are written in extensions/c2pa-soft-binding-entries.json. extensions/iscc.md: ISO 24138's codec, ISCC-SEQ, Instance-, Image- and Audio-Codes and the ISCC-CODE from the IEP texts, replaying the public test vectors; WAI's integer pre-processing. extensions/detection.md: wai.media.detection, a detector's signed verdict at an operating point named by digest, its evidence a robustness record of binding type detector; refused as provenance, never a change to an origin claim's class. Corpora c2pa-identity/, iscc/ and detection/, each with a second implementation in Python. Co-Authored-By: Claude Opus 5.5 <[email protected]>
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live-conformance/detection — detection verdicts
The corpus of extensions/detection.md §8: cases of origin claims,
robustness records and detection verdicts, accepted and refused, and what a verifier states of each.
Files. vectors.json names the stand-in detector and its definition, and lists the cases,
each its name, its provenance, robustness and verdicts (paths of the records given, in
order), requireEvidence (the policy evidence of §5.1) and expect. records/ holds every
record once, named by its role and the first 16 hexadecimal digits of the SHA-256 of its text.
Equivalence. A conforming verifier given a case's records and policy reaches the outcome
expect states (§5): for refuse, the reason of §7, the list and the index; for accept,
what §5.3 states: each origin claim's link, subject and class, and each verdict's link,
subject, detector, verdict, besideClaim and evidence.
The cases.
- Accepted:
verdicts-beside-claims(two verdicts that agree with their claims and two that disagree, the classes as signed),claims-without-verdicts(the same claims, the same classes), andverdict-without-claim. - One refused case for each reason of §7, some reasons more than once; each name says its defect.
Provenance. wai_detection_vectors gen writes every file but this one from fixed seeds:
every key is SHA-256 of a label, and no key is one anyone holds. The detector,
wai-detector:conformance, scores a picture by the share of its bright pixels: it detects nothing
about how a picture was made and stands for a detector a verifier does not implement. Its
robustness records are measured: the generator runs it at each threshold over two bright pictures
and two dark ones it draws, under four attacks of robustness-evidence §4. The verdicts' scores are
its scores of five pictures the generator draws, named by the content hash of each as a PNG.
Checked by. wai_detection_vectors verify and tests/detection.rs in wai-rs, and
../detection_verify.py, the second implementation, written from the extension's text, which
verifies the robustness records with ../robustness_verify.py, requires every mutated copy of an
accepted case to be refused and every one of its own checks, dropped, to be caught.