On: MS Paint and Photos inivisibly watermark even locally generated output with GUID

[baby_souffle]

Well that was fast!

> build their own photo-sensor simulator and plug _that_ in to the camera's motherboard to feed it a "real" image?

Already been done!

https://hackerfactor.com/blog/index.php?/archives/1102-C2PA-...

TL;DR: Strong cryptography over untrusted data does not make the data more trustworthy.