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JPEG XL Content Provenance

Sign, embed, and verify C2PA manifests in JPEG XL files (.jxl)

What Is JPEG XL Provenance?

Next-generation image format designed to replace JPEG with superior compression and quality. JXL provenance future-proofs content as browser adoption grows.

With Encypher, JPEG XL files carry their own cryptographic proof of origin. A C2PA manifest is embedded directly into the file, recording who created it, when, and whether it has been modified. Anyone can verify a signed JPEG XL file for free, without authentication.

How C2PA Manifests Are Embedded in JPEG XL Files

MIME Type
image/jxl
File Extensions
.jxl
Embedding Method
Custom JUMBF/COSE structural embedding (c2pa-python does not yet natively support JXL)
Container Type
Custom JUMBF/COSE
Verification Pipeline
Custom JUMBF/COSE structural verification (Encypher implementation)

The C2PA manifest contains a JUMBF (JPEG Universal Metadata Box Format) store with COSE-signed claims. For JPEG XL files, the manifest is stored using custom jumbf/cose structural embedding (c2pa-python does not yet natively support jxl). The signing process does not alter the image content itself. The manifest is metadata, not a modification of the pixels.

Use Cases for JPEG XL Provenance

  • Next-gen web delivery
  • Photography archives
  • High-quality image distribution

How to Sign JPEG XL Content with Encypher

JPEG XL signing is available at the Enterprise tier through the unified /sign/media API endpoint. Upload your JPEG XL file, and the API returns a signed copy with an embedded C2PA manifest.

curl -X POST https://api.encypher.com/api/v1/sign/media \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -F "file=@example.jxl" \
  -F "title=My JPEG XL Content" \
  -F "action=c2pa.created" \
  -o signed.jxl

Verify JPEG XL Provenance (Free)

Verification is free and requires no authentication. Any third party can verify a signed JPEG XL file to confirm its origin, check for tampering, and read the embedded rights information.

Related Formats

Learn More About Content Provenance