C2PA vs SynthID: what is the difference?
C2PA vs SynthID: what is the difference?
Both C2PA and SynthID try to make AI-generated media identifiable — but they solve different problems and work at different layers.
C2PA — provenance you can inspect
C2PA (Content Credentials) attaches a signed manifest to a file: who made it, what edited it, when, and whether AI was involved. It is portable metadata that survives editing inside supporting apps and can be read by any compatible verifier. Its strength is a human-readable, auditable history of the file.
SynthID — a watermark inside the pixels
SynthID embeds a steganographic watermark directly into the image, audio, or video — subtle changes to pixels or samples that are imperceptible to humans but detectable by a matching detector. It does not require extra metadata and can survive some cropping and compression. Its strength is resilience when the manifest has been stripped.
Why you need both
The two are complementary, not competing:
- A C2PA manifest can be removed by re-saving or screenshotting the file.
- A SynthID watermark can be degraded by heavy editing, though it tolerates light changes better than metadata.
When OpenAI, Google, and others ship both on the same output, a verifier that checks the C2PA manifest and a detector that scans for a SynthID watermark gives you two independent signals. One missing signal is not proof of anything — which is exactly why “no credentials found” should never be read as “this is real.”