alt Hacker NewsReading around a bit, yes to Netflix adding anti-piracy measures, maybe to folks recording HDMI/DisplayPort.
Apparently, Netflix is using steganography/content watermarks in their 4k content itself to trace users who are pirating. This is from a totally unsourced Reddit thread[0] but they do reference a real company which claims to do this watermarking[1]. The claim is that in addition to Netflix requiring 4k content to be available only on platforms with Trusted Execution Environments[2], Netflix also encodes each ~10 second "chunk" of the video stream into at least 2 different versions: an Y and a Z version. Then, they serve each customer a unique series of chunks when that customer streams their content, e.g. YYZYZZZYZYYZYZYYZZYZYYZ. Then when content leaks, Netflix can examine each chunk of the leaked content to extract the ID of the user who streamed the content. Apparently, Netflix can encode a lot more than just the userID, they can also encode stuff like the individual device ID, the TEE key ID, etc.
I know you might be thinking "I could do something to defeat that" and you're probably right (e.g. take streams from multiple users and intercut them so that the bits of the watermark through time are being constantly shuffled), but I'll also bet that there's many layers of steganography we don't know about, and unless you get them all, you'll not escape scot-free.
[0] - https://www.reddit.com/r/Piracy/comments/1rqkyjg/with_a_lot_...
[1] - https://irdeto.com/video-entertainment/irdeto-anti-piracy
[2] - https://en.wikipedia.org/wiki/Trusted_execution_environment
Replies
Not that I would ever pirate a movie because I'm a good boy, but I remember the Cinavia DRM that affected Blu-ray players thirteen years ago.
I'm not 100% sure how it worked, but I guess it could do a similar kind of steganography-style thing to the audio track, where they would embed keys silently and the blu-ray player would check against that.
I'm not sure if anyone actually ever managed to defeat it, I think they just stopped implementing it in streaming boxes.
>you'll not escape scot-free.
What are they gonna do? Ban your account? You don't need to go through KYC to get a netflix account, so what's preventing you from using a prepaid card to sign up for another account?
I can’t lie It’s a pretty neat way to track who’s recording
Yes, apparently this is what Netflix is doing.
But the only real world impact is that the device that was used to stream that 4K content gets blacklisted at the hardware level.
To workaround this, piracy groups try to batch 4K rips because they know that the device will be burned soon after they upload the content. They then acquire another device, and the game of whack-a-mole continues.
There are some interesting discussions in this HN thread: https://news.ycombinator.com/item?id=46803451