Configuring C2PA Tool Settings
In the previous lesson we looked at how to install the c2patool and signed our first asset and now we’re going to configure it to handle a series of use cases that we’re going to look at in the upcoming lessons.
To add some context to the things that we’re going to configure, what I want to do is walk through a C2PA manifest store and talk about some of the components at a really high level. We’ll use this exploration to reveal the things we need to configure for our manifest builder and signer.
Example manifest store
Code from the lesson
// manifest.json
{
"claim_generator_info":[{
"name": "Demo Camera App",
"version": "1.0.0"
}]
}
# settings.toml
[builder]
created_assertion_labels = [
"c2pa.actions",
"c2pa.thumbnail.claim",
"c2pa.thumbnail.ingredient",
"c2pa.ingredient"
]
[builder.actions.auto_created_action]
enabled = false
[builder.actions.auto_opened_action]
enabled = true
[signer]
[signer.local]
alg = "es256"
sign_cert = """-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
-----BEGIN CERTIFICATE-----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==
-----END CERTIFICATE-----
"""
# Private key
private_key = """-----BEGIN PRIVATE KEY-----
MIGHAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBG0wawIBAQQgfNJBsaRLSeHizv0m
GL+gcn78QmtfLSm+n+qG9veC2W2hRANCAAQPaL6RkAkYkKU4+IryBSYxJM3h77sF
iMrbvbI8fG7w2Bbl9otNG/cch3DAw5rGAPV7NWkyl3QGuV/wt0MrAPDo
-----END PRIVATE KEY-----
"""
tsa_url = "http://timestamp.digicert.com"
# c2patool command to sign the image
./c2patool --settings config/settings.toml capture-unsigned.jpg \
-m config/manifest.json -o capture-signed.jpg
Getting more help
You can access the CAI Docs to learn more about implementing Content Credentials. If you have questions about this video, there is a forum set up on the CAI Discord for each video. You can access discussion for this video here. We would love to see your questions there!