Manifest examples

Example assets

The example-assets repository contains some sample assets that demonstrate Content Credentials, including links to view the corresponding manifest reports from the C2PA Tool and to inspect the assets using Verify. See the README as rendered in GitHub Pages.

Examples from C2PA Tool

The command-line C2PA Tool, c2patool, is helpful when developing applications to work with manifest data. When saving a manifest, it has two modes:

• Standard mode (the default), where it saves a manifest file in JSON format, which is simplified and slightly different from the underlying binary manifest structure.
• Detailed mode (specified with the -d option), where it saves a file that more closely reflects the actual structure of the binary data, including assertions with JUMBF URLs and their associated hashes.

Simple manifest

This manifest was saved using c2patool with no options.

{
  "active_manifest": "contentauth:urn:uuid:5a08e472-974c-422e-b38a-d6c7326481a5",
  "manifests": {
    "contentauth:urn:uuid:5a08e472-974c-422e-b38a-d6c7326481a5": {
      "claim_generator": "make_test_images/0.12.0 c2pa-rs/0.12.0",
      "title": "C.jpg",
      "format": "image/jpeg",
      "instance_id": "xmp:iid:e928fac1-8473-4c70-8219-369e91d4e58d",
      "thumbnail": {
        "format": "image/jpeg",
        "identifier": "contentauth-urn-uuid-5a08e472-974c-422e-b38a-d6c7326481a5.jpg"
      },
      "ingredients": [],
      "assertions": [
        {
          "label": "stds.schema-org.CreativeWork",
          "data": {
            "@context": "http://schema.org/",
            "@type": "CreativeWork",
            "author": [
              {
                "@type": "Person",
                "name": "Gavin Peacock"
              }
            ]
          },
          "kind": "Json"
        },
        {
          "label": "c2pa.actions",
          "data": {
            "actions": [
              {
                "action": "c2pa.created"
              },
              {
                "action": "c2pa.drawing",
                "parameters": {
                  "name": "gradient"
                }
              }
            ]
          }
        }
      ],
      "signature_info": {
        "issuer": "C2PA Test Signing Cert",
        "cert_serial_number": "720724073027128164015125666832722375746636448153",
        "time": "2022-08-19T19:03:41+00:00"
      },
      "label": "contentauth:urn:uuid:5a08e472-974c-422e-b38a-d6c7326481a5"
    }
  }
}

Detailed manifest

This manifest was saved using c2patool with the -d option. Even though it was generated for the same asset and Content Credentials as the simple manifest example, you can see that it's about twice as long.

{
  "active_manifest": "contentauth:urn:uuid:5a08e472-974c-422e-b38a-d6c7326481a5",
  "manifests": {
    "contentauth:urn:uuid:5a08e472-974c-422e-b38a-d6c7326481a5": {
      "claim": {
        "alg": "sha256",
        "assertions": [
          {
            "hash": "BzyThXbTh88KAa5Wb8ckQHMH+Z+noRAUxuv0OmhSQes=",
            "url": "self#jumbf=c2pa.assertions/c2pa.thumbnail.claim.jpeg"
          },
          {
            "hash": "lEORvVMPdP8FK5rTLk0zF0SttylTbG5r/6t4Svx0lXA=",
            "url": "self#jumbf=c2pa.assertions/stds.schema-org.CreativeWork"
          },
          {
            "hash": "42l0mSt4ue0hIk5YSZ3Q8cwcotNphWsScwvDyq+qyP8=",
            "url": "self#jumbf=c2pa.assertions/c2pa.actions"
          },
          {
            "hash": "PMfHnzmyMA2CWqP4rdBd6GrORasLnYmtnFkpAnaIs94=",
            "url": "self#jumbf=c2pa.assertions/c2pa.hash.data"
          }
        ],
        "claim_generator": "make_test_images/0.12.0 c2pa-rs/0.12.0",
        "claim_generator_info": null,
        "dc:format": "image/jpeg",
        "dc:title": "C.jpg",
        "instanceID": "xmp:iid:e928fac1-8473-4c70-8219-369e91d4e58d",
        "signature": "self#jumbf=c2pa.signature"
      },
      "assertion_store": {
        "c2pa.thumbnail.claim.jpeg": "<omitted> len = 31659",
        "c2pa.actions": {
          "actions": [
            {
              "action": "c2pa.created"
            },
            {
              "action": "c2pa.drawing",
              "parameters": {
                "name": "gradient"
              }
            }
          ]
        },
        "c2pa.hash.data": {
          "alg": "sha256",
          "exclusions": [
            {
              "length": 51179,
              "start": 20
            }
          ],
          "hash": "DcGR4k9M6aLXXCeDii4tSdX45rrIM5HSr1Wy/czQ6ro=",
          "name": "jumbf manifest",
          "pad": "<omitted>"
        },
        "stds.schema-org.CreativeWork": {
          "@context": "http://schema.org/",
          "@type": "CreativeWork",
          "author": [
            {
              "@type": "Person",
              "name": "Gavin Peacock"
            }
          ]
        }
      },
      "signature": {
        "alg": "ps256",
        "issuer": "C2PA Test Signing Cert",
        "time": "2022-08-19T19:03:41+00:00"
      }
    }
  },
  "validation_status": [
    {
      "code": "claimSignature.validated",
      "url": "self#jumbf=/c2pa/contentauth:urn:uuid:5a08e472-974c-422e-b38a-d6c7326481a5/c2pa.signature",
      "explanation": "claim signature valid"
    },
    {
      "code": "assertion.hashedURI.match",
      "url": "self#jumbf=c2pa.assertions/c2pa.thumbnail.claim.jpeg",
      "explanation": "hashed uri matched: self#jumbf=c2pa.assertions/c2pa.thumbnail.claim.jpeg"
    },
    {
      "code": "assertion.hashedURI.match",
      "url": "self#jumbf=c2pa.assertions/stds.schema-org.CreativeWork",
      "explanation": "hashed uri matched: self#jumbf=c2pa.assertions/stds.schema-org.CreativeWork"
    },
    {
      "code": "assertion.hashedURI.match",
      "url": "self#jumbf=c2pa.assertions/c2pa.actions",
      "explanation": "hashed uri matched: self#jumbf=c2pa.assertions/c2pa.actions"
    },
    {
      "code": "assertion.hashedURI.match",
      "url": "self#jumbf=c2pa.assertions/c2pa.hash.data",
      "explanation": "hashed uri matched: self#jumbf=c2pa.assertions/c2pa.hash.data"
    },
    {
      "code": "assertion.dataHash.match",
      "url": "self#jumbf=/c2pa/contentauth:urn:uuid:5a08e472-974c-422e-b38a-d6c7326481a5/c2pa.assertions/c2pa.hash.data",
      "explanation": "data hash valid"
    }
  ]
}