One thing I’m concerned about is recording equipment leaving identifiable information without us knowing about it.

  • मुक्त@lemmy.ml
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    10 hours ago

    Photos taken by digital cameras are also trackable in a similar way as prints taken from a printer. I recall reading they were trying to identify the device after a Harry Potter book was leaked by someone taking digital photographs.

      • HiddenLayer555@lemmy.ml
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        1 hour ago

        Even without EXIF data I would bet the actual encoding of the image will be identifiable to a specific instance of the camera software.

        Similar to how websites fingerprint your browser by rendering something in the canvas or webgl and sending back the rendered image. The exact same rendering procedure will produce slightly different images for each browser instance. I suspect browsers are fully aware and complicit in this because why the actual fuck would they not make the rendering engines deterministic to their inputs?!

      • ReversalHatchery@beehaw.org
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        3 hours ago

        or just the individual characteristics and flaws of the lens/sensor/postprocessing software, some of which can be unique per device, and potentially comparable to other photos made with it.

    • space_comrade [he/him]@hexbear.net
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      9 hours ago

      Was it just EXIF information or was it something embedded in the pixels? If it’s just EXIF that’s something you can scrub from the file easily.

      • chgxvjh [he/him, comrade/them]@hexbear.net
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        8 hours ago

        The Harry Potter thing was EXIF https://www.eff.org/deeplinks/2007/07/harry-potter-and-digital-fingerprints

        But pictures can also be traced back to a camera based on irregularities in the camera sensor https://www.scientificamerican.com/article/tracing-photos-back-to-the-camera-that-snapped-them/

        Unlike with the printers, there is probably no database of the CMOS sensor irregularities of all cameras ever made. But if you upload pictures under your government name and the take pictures with the same camera and share them anonymously, this could be traced back to you in theory.

        • LENINSGHOSTFACEKILLA [he/him]@hexbear.net
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          8 hours ago

          sensor pattern noise is recognizable to an extent with pros, but usually its paired with highlight rolloff and other similar qualities. For instance, when I watch a movie, I can figure, okay, this was probably one of the arri’s rather than a RED, etc. Sometimes, especially with a bit of knowledge on how/where they shot this, you can get an even better idea, close to a specific model. Of course if you’re watching an actual movie, this is all after color correction so its more obvious if you have the raw files.

          anyway, my point is, people who work with the cameras and files can definitely have at least a good idea of what camera something was shot with, but you’d really need a huge database and computers to do the work to match it exactly. I have colleagues that will show me something they worked on, with cameras they don’t own and between the group of us, someone can immediately spot what camera it was shot on. but! like you said, if you post pictures on the internet, and then more pictures/videos with the same camera elsewhere, yeah it should be theoretically possible to match them with sensor noise pattern. they could at least prove its the same model. i’m not sure how much it differentiates between same camera models, but i can recognize my camera models dnp easy peasy. i have not had any caffeine yet so this is likely a jumbled mess of a thought and i apologize.

          • chgxvjh [he/him, comrade/them]@hexbear.net
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            8 hours ago

            And they can do that based on the way your write text posts too, so probably not worth worrying about camera sensor fingerprinting too much.

            Just don’t post about your insurrection plans on public forums in general, with or without photos.

      • oscardejarjayes [comrade/them]@hexbear.net
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        8 hours ago

        Cameras generally have barely noticeable, but uniquely identifiable, defects that will consistently affect pictures. So if you post a photo on your personal Social Media, and then you post a photo from the same camera on Hexbear, those two things could be connected. Just because it can happen doesn’t mean it’s practical, though.

        I have no idea if this is what’s been used with the Harry Potter thing.

      • TheSlad@sh.itjust.works
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        3 hours ago

        Any image editing tool like mspaint or similar. Just copy paste the pixels into a new image file. Though, the program youre using will probably still add it’s own metadata to the new file, but all the original metadata from the camera won’t be there.

      • thevoidzero@lemmy.world
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        7 hours ago

        That’s the obvious one. But you can also add data to images by adding tiny values to the pixels, it’ll still look the same to us (same as printer tiny dots).

        I don’t know if phones actually do this. Just saying it’s possible.

        But many uploading sites optimize the images, so it’ll be gone on reshare, but they could get it on first upload.