Interestingly, reading the fourth chapter, the first time this technique of identifying the sensor based on the specific noise characteristics was 2005. I bet this was tacitly well known far before 2005.
There are many camera from pre - 2005 that did dark frames and flat frames, for example Sinar digital backs. They all came with a CD with the unique calibration file for the back to tune out these characteristics to a large degree. Without them, you can see literally see the difference in exposure down the center of the image from the two stitched lithography mask shots required to make large CCDs at the time.
Most full-frame sensors are still stitched from two exposures side-by-side (digital MF is four exposures, real medium format sensors six), but they're matched well-enough (or the raw files are already compensating for this) that it's only an issue for the astro people nowadays.
Interesting, I'm an amateur astronomer and didn't know that, I've never noticed any stitching artifacts when shooting with my Canon 6D. Found a relevant discussion on DPreview[1] which suggests that not all cameras do this, it appears to be more noticeable on some Sony cameras at first glance of the thread.
Based on my experience with Sinar digital backs, which spit out a raw, bias, dark and flat frame all independently, I think most cameras include this calibration hardcoded into the raw, because otherwise it is extremely easy to see! I know Phase One backs have calibrations that compensate for this, column errors, and hot pixels in their IIQ raws by default.
Removing noise is difficult if not impossible. The best someone could probably do is find a sensor whose noise characteristics are a superposition of their cameras and another additive distribution. There are simple ways to defeat this, but it's best not to share them, as I think the only people ruñning from this kind of tracking would be sketchy criminals.
Completely removing noise is difficult-to-impossible. Attenuating the noise enough to impart a new noise pattern is much easier, though (not saying it's easy, just easier).
I did this sort of thing decades ago as part of larger system used for research.
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There are many camera from pre - 2005 that did dark frames and flat frames, for example Sinar digital backs. They all came with a CD with the unique calibration file for the back to tune out these characteristics to a large degree. Without them, you can see literally see the difference in exposure down the center of the image from the two stitched lithography mask shots required to make large CCDs at the time.
[1] https://www.dpreview.com/forums/thread/3949870
edit: another discussion: https://www.dpreview.com/forums/thread/3949529
Completely removing noise is difficult-to-impossible. Attenuating the noise enough to impart a new noise pattern is much easier, though (not saying it's easy, just easier).
I did this sort of thing decades ago as part of larger system used for research.
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