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provemark/c2pa-verifier

Verifier for C2PA Content Credentials in pure PHP: JPEG, PNG, WebP and ISOBMFF, with c2patool's verdict. Read and verify only; no signing, no keys, no network.

12 good first / help-wanted issues · PHP · last activity Sep 23, 2026

0 stars 0 forks 0 watchers PHP MIT License
c2pa cbor content-authenticity content-credentials cose digital-signatures isobmff jumbf ocsp php provenance rfc3161 x509
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12 Open Issues Need Help Last updated: Sep 23, 2026

Open Issues Need Help

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Every non-exempt action should carry a digitalSourceType (PRED-ASSE-025) about 1 month ago
good first issue help wanted conformance
provemark/c2pa-verifier
0

Verifier for C2PA Content Credentials in pure PHP: JPEG, PNG, WebP and ISOBMFF, with c2patool's verdict. Read and verify only; no signing, no keys, no network.

PHP
#c2pa#cbor#content-authenticity#content-credentials#cose#digital-signatures#isobmff#jumbf#ocsp#php#provenance#rfc3161#x509
Support trust anchors with notBefore/notAfter gating (PRED-CRYP-006) about 1 month ago
help wanted conformance waiting upstream
provemark/c2pa-verifier
0

Verifier for C2PA Content Credentials in pure PHP: JPEG, PNG, WebP and ISOBMFF, with c2patool's verdict. Read and verify only; no signing, no keys, no network.

PHP
#c2pa#cbor#content-authenticity#content-credentials#cose#digital-signatures#isobmff#jumbf#ocsp#php#provenance#rfc3161#x509
Read the iat claimed time of signing, and the timeOfSigning codes (PRED-CRYP-018, -019) about 1 month ago
help wanted conformance waiting for a file
provemark/c2pa-verifier
0

Verifier for C2PA Content Credentials in pure PHP: JPEG, PNG, WebP and ISOBMFF, with c2patool's verdict. Read and verify only; no signing, no keys, no network.

PHP
#c2pa#cbor#content-authenticity#content-credentials#cose#digital-signatures#isobmff#jumbf#ocsp#php#provenance#rfc3161#x509
Check the syntax of custom status codes recorded by an ingredient (PRED-STRU-002) about 1 month ago
good first issue help wanted conformance
provemark/c2pa-verifier
0

Verifier for C2PA Content Credentials in pure PHP: JPEG, PNG, WebP and ISOBMFF, with c2patool's verdict. Read and verify only; no signing, no keys, no network.

PHP
#c2pa#cbor#content-authenticity#content-credentials#cose#digital-signatures#isobmff#jumbf#ocsp#php#provenance#rfc3161#x509
Validate the icon field in claim_generator_info (PRED-STRU-009) about 1 month ago
good first issue help wanted conformance
provemark/c2pa-verifier
0

Verifier for C2PA Content Credentials in pure PHP: JPEG, PNG, WebP and ISOBMFF, with c2patool's verdict. Read and verify only; no signing, no keys, no network.

PHP
#c2pa#cbor#content-authenticity#content-credentials#cose#digital-signatures#isobmff#jumbf#ocsp#php#provenance#rfc3161#x509
Verify the signerBinding signature of c2pa.session-keys (PRED-CRYP-024) about 1 month ago
help wanted conformance
provemark/c2pa-verifier
0

Verifier for C2PA Content Credentials in pure PHP: JPEG, PNG, WebP and ISOBMFF, with c2patool's verdict. Read and verify only; no signing, no keys, no network.

PHP
#c2pa#cbor#content-authenticity#content-credentials#cose#digital-signatures#isobmff#jumbf#ocsp#php#provenance#rfc3161#x509
Fall back to c2pa.hash.multi-asset when the hard binding fails (PRED-ASSE-021) about 1 month ago
help wanted conformance
provemark/c2pa-verifier
0

Verifier for C2PA Content Credentials in pure PHP: JPEG, PNG, WebP and ISOBMFF, with c2patool's verdict. Read and verify only; no signing, no keys, no network.

PHP
#c2pa#cbor#content-authenticity#content-credentials#cose#digital-signatures#isobmff#jumbf#ocsp#php#provenance#rfc3161#x509
Read the c2pa.time-stamp assertion (PRED-TIME-002, -003) about 1 month ago
help wanted conformance
provemark/c2pa-verifier
0

Verifier for C2PA Content Credentials in pure PHP: JPEG, PNG, WebP and ISOBMFF, with c2patool's verdict. Read and verify only; no signing, no keys, no network.

PHP
#c2pa#cbor#content-authenticity#content-credentials#cose#digital-signatures#isobmff#jumbf#ocsp#php#provenance#rfc3161#x509
Implement c2pa.alternative-content-representation (PRED-ASSE-013, -014, -026) about 1 month ago
help wanted conformance
provemark/c2pa-verifier
0

Verifier for C2PA Content Credentials in pure PHP: JPEG, PNG, WebP and ISOBMFF, with c2patool's verdict. Read and verify only; no signing, no keys, no network.

PHP
#c2pa#cbor#content-authenticity#content-credentials#cose#digital-signatures#isobmff#jumbf#ocsp#php#provenance#rfc3161#x509
Three shape checks on the BMFF hash assertion (PRED-BMFF-001, -002, -004) about 1 month ago
help wanted conformance
provemark/c2pa-verifier
0

Verifier for C2PA Content Credentials in pure PHP: JPEG, PNG, WebP and ISOBMFF, with c2patool's verdict. Read and verify only; no signing, no keys, no network.

PHP
#c2pa#cbor#content-authenticity#content-credentials#cose#digital-signatures#isobmff#jumbf#ocsp#php#provenance#rfc3161#x509
c2pa.external-reference must not name forbidden labels (PRED-ASSE-027) about 1 month ago
help wanted conformance
provemark/c2pa-verifier
0

Verifier for C2PA Content Credentials in pure PHP: JPEG, PNG, WebP and ISOBMFF, with c2patool's verdict. Read and verify only; no signing, no keys, no network.

PHP
#c2pa#cbor#content-authenticity#content-credentials#cose#digital-signatures#isobmff#jumbf#ocsp#php#provenance#rfc3161#x509
reviewRatings must not sit beside a humanEntry dataSource (PRED-ASSE-024) about 1 month ago
good first issue help wanted conformance
provemark/c2pa-verifier
0

Verifier for C2PA Content Credentials in pure PHP: JPEG, PNG, WebP and ISOBMFF, with c2patool's verdict. Read and verify only; no signing, no keys, no network.

PHP
#c2pa#cbor#content-authenticity#content-credentials#cose#digital-signatures#isobmff#jumbf#ocsp#php#provenance#rfc3161#x509