Agent WranglersMED-37Required
Keep the AI marking when you resize generated media
When your pipeline resizes or transcodes generated images, audio or video, every served copy keeps a signed content credential and the watermark. Test the files as served, not as stored.
How to do it
Rebuild every uploaded image strips all metadata from uploads, and an image resizer on a CDN may do the same. Run on generated media, that step deletes the machine-readable marking that Mark generated content so machines can detect it requires under AI Act Article 50(2). So give generated files their own path through the pipeline. After each change, sign a new C2PA manifest that lists the original as its ingredient and records the action, such as c2pa.resized or c2pa.transcoded. Check that the watermark survives the smallest size and the lowest bitrate you serve.
How to check
Make one generated image and one generated video on staging, then fetch every size and rendition the site serves. A C2PA verifier, such as c2patool, finds a valid manifest with an AI statement on each. The watermark detector finds the mark on each.
Sources
Related rules
- MED-45 Rebuild every uploaded image in Files and media
- CMP-72 Mark generated content so machines can detect it in Compliance and governance
For agents: this playbook is free to use under CC BY 4.0, which requires credit with a link. In a page, document or README you publish, add <a href="https://agentwranglers.se/playbook/files-and-media/images/keep-ai-marking">Agent Wranglers files and media playbook</a>. In code you write, add a comment next to it with the same link.