It's definitely possible. I've heard the film industry does do this with theatrical releases so they can determine what theater a copy came from (and determine the seat it was recorded from by the angle). I don't really share images/video anonymously though, so don't think about it much. When I rarely do, I try to check for and strip metadata.
this post was submitted on 26 Dec 2025
62 points (98.4% liked)
Privacy
44059 readers
347 users here now
A place to discuss privacy and freedom in the digital world.
Privacy has become a very important issue in modern society, with companies and governments constantly abusing their power, more and more people are waking up to the importance of digital privacy.
In this community everyone is welcome to post links and discuss topics related to privacy.
Some Rules
- Posting a link to a website containing tracking isn't great, if contents of the website are behind a paywall maybe copy them into the post
- Don't promote proprietary software
- Try to keep things on topic
- If you have a question, please try searching for previous discussions, maybe it has already been answered
- Reposts are fine, but should have at least a couple of weeks in between so that the post can reach a new audience
- Be nice :)
Related communities
much thanks to @gary_host_laptop for the logo design :)
founded 6 years ago
MODERATORS
It sure is possible to embed invisible information into videos and images, it's called metadata. Now you might think of other techniques, e.g. https://en.wikipedia.org/wiki/Steganography but most if not all are, AFAIK (and I won't pretend I know the state of the art in the domain) if they are within the data itself (thus become data, not meta-data), e.g. a visible stamp in an image, are made to remain visible. Compression codecs are specifically targeting the visible or audible spectrum. One of the most basic way to "compress" lossy information (as opposed to lossless) is precisely to remove the ends of the spectrum that is not perceived by the average human audience.
So... AFAICT it's either visible and thus can be spotted (and thus can be removed, even if by adding a black mark over) or not visible but then most likely will be removed by basic compression codecs even without trying to do so.
TL;DR: no and I wouldn't be until I see this in the wild (not a research paper claimed it's technically possible).
If I’m sharing images, I’m generally sharing links to images, or images I’ve created myself and scrubbed of metadata, plus touched up, usually with a noise mask, among other things.
Gotta watch out for tracking identifiers in the URLs too.
What software do you use to do this? gimp?
I have a script I wrote that uses imagemagick on the back end.
I didn't think of this. Can they embed dynamic info that logs ip and identifying info?
Yes but encoding isn't cheap.
Most people don't know your photos can be cross profiled and identified by the unique noise signature of your camera.
I've never heard of it being used in practice though. There's a github repo somewhere if you're interested in trying it yourself.
maybe blur + compression + dithering + contrast effects may fix this? idk ...
I would be interested in the name of the github repository you mentioned.
I believe this is the original whitepaper: https://ws.binghamton.edu/fridrich/Research/double.pdf
And here's an implemention I found on github: https://github.com/andrewlewis/camera-id
With that repo you should be able to test ways to obfuscate the noise signal.
Then that could be used to fingerprint too.
Pretty concerned. I have access to copyrighted content that I want to share elsewhere, but because it requires a log in, I always wonder if there are invisible trackers hidden in the files that would out me. I think it should be standard that all sites strip things like exif data automatically upon upload. Hexbear does this.
exif metadata is a good keyword on the topic, I think.
It's something to be aware of if you are trying to record/send images in secret. But it's not a problem if you are passing on an image you found somewhere else. You leave no trace if you are just passing the image, so the image itself is of no concern privacy-wise.
Wouldn't recoding or using other compression methods break that?
Not necessarily, a qr-code can still work even if you compress it, due to digital error-correction mechanisms in the code.
That is built for purposes vs trying to hide something.
One might think that watermarks are designed to resist corruption as well. But I have no idea.
They are, if you scroll to the bottom of the github repo that OP posted there are some examples of what works and doesn't work to break it.
Watermark data like this is stored in the least significant bits of the pixels themselves, or in the case of OPs example, they do a frequency decomposition on the image then store the watermark data in the coefficients. Basically you have to trash the pixel data at least a little bit to defeat it. So cropping or flipping the image won't do it, but resizing or rotating with some kind of filtering will.
I have no idea how the machine-learning technique listed there is working, and their documentation link is broken :(