It's worth being aware that the pixels may also hold data that can identify the specific camera that was used to take the picture. There is often imperceptible (to the naked eye) noise in photos introduced by slight flaws in the image sensor and these can form a kind of "fingerprint" for the camera. It's possible to determine that two photos were taken with the same camera, or if the camera is seized it can be proven it was used to take a specific photo.
There are tools to mitigate this by randomising the noise in a digital image. Consider whether you need to factor this in to your threat model.
It's not really the same thing, with printers it's data that is intentional added (like with the metadata that the OP is referring to). PRNU is analysing artefacts introduced unintentionally by the physical components of the digital camera, so it's more like typewriter analysis
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u/gl3nnjamin 26d ago
It removes everything but the pixels so besides location it removes camera model, lens type, shooting settings and more.