john01dav 4 hours ago

Even with all of this onerous encryption and DRM, it's not hard to find pirated copies of movies. It makes me think that the sacrifice in ownership rights for the theaters over their equipment isn't worth it.

  • perryflynn 2 hours ago

    It also contains watermarks. So theatres which failed to prevent recording will run into serious issues. See https://dcpomatic.com/forum/viewtopic.php?t=2372

    • coppsilgold a minute ago

      If the software to watermark is widely available (as it appears to be) then an adversary has all they need to corrupt any existing watermark.

      These steganographic watermarks depend on no knowledge of the process.

      If you obtain two or more copies of the decrypted content you will be able to diff them and work out what you need to corrupt even without knowledge of the watermarking process. This probably won't work with pirated CAM's or if it does the result will not be worth sharing.

    • thr0w 38 minutes ago

      NexGuard is a wild product.

      • stavros 23 minutes ago

        The flea repellant?

  • gruez 3 hours ago

    Most pirated copies aren't from theatrical releases; they mostly come out when the titles are available on streaming/blu-ray. DRM might be a failure in other fields, but it's working pretty well in this particular case.

  • ajsnigrutin 3 hours ago

    Yep, and those pirated copies are DRM free, work everywhere, no HDCP and other crap, no internet connection needed, so they're "better" in that way too (not just price-wise).

    • eastbound 3 hours ago

      Totally possible that watermark identifies cinemas and showtimes uniquely, and that pirates are due for a lifetime of prosecution. Or that studios will shut down some cinemas, until it stops.

      For 15 years you let paid options progress. Then fewer people pirate, then you catch the rest. At the beginning you don’t see it putting its clamps; then suddenly you don’t find piracy anywhere.

      • ajsnigrutin 2 hours ago

        Yes, and those paid options were one subscription that had "everything". Then paid options broke up into 5 different subscriptions, some not allowing more than 2 devices, some having ads in paid plans, some not available in your country, some only having seasons 3 and 5 of the series, some having the series you wanted to watch but remove it half way through, some give you a "buy" button for the media, but then take the movies away after a few months, etc.

        And people go back to piracy, because the user experience is better.

ddtaylor 3 hours ago

How are groups getting the high quality digital dumps of some movies then?

  • pain_perdu 3 hours ago

    I don't think new theatre releases are generally getting leak in digital formats anymore until they hit streaming which can sometimes be as soon as weeks or couple months after original release. Obviously 'tele-syncs' (cameras capturing the film) still exist but that wasn't your question. The one exception to this can be oscar movie season when studios release films via a special Apple TV app and that be be slightly less secure (though still water-marked).

    I would ask you to support your claim of 'high quality digital dumps' by citing one that has come out in the last couple years. See https://predb.net/

    • lurk2 2 hours ago

      > A telesync (TS) is a bootleg recording of a film recorded in a movie theater, often (although not always) filmed using a professional camera on a tripod in the projection booth. The audio of a TS is captured with a direct connection to the sound source (often an FM microbroadcast provided for the hearing-impaired, or from a drive-in theater). If a direct connection from the sound source is not possible, sometimes the bootlegger will tape or conceal wireless microphones close to the speakers, as it is better than a mic on the camera. A TS can be considered a higher quality type of cam, that has the potential of better-quality audio and video.

      https://en.wikipedia.org/wiki/Telesync

  • kmeisthax 2 hours ago

    Hollywood is stupid and eroded its own economic advantage by putting everything on streaming. This was already known, but it also makes antipiracy operations much, much harder.

    Ripping a stream is always going to be easier than getting any unprotected video footage out of a movie theater. The stream is in your own home, you own and can tamper with all the equipment involved in playing it, and the economics of CDNs prevent robust traitor-tracing schemes[0] that could be used to hunt you down.

    In contrast, movie theaters are public locations, so every one of them is a known entity. The entire supply chain for movie projection is controlled. And that makes traitor-tracing a lot easier. All the hackers pointing out that DRM is fundamentally breakable are ignoring the fact that that only matters iff you're anonymous and untraceable. Otherwise, they won't bother making the DRM stronger, they'll just arrest people until the movies stop leaking.

    It's the XKCD laptop wrench story[1] in reverse. The crypto nerd imagines DRM to be easily broken trash, but the reality is that the security of the DRM is in the $5 wrench, not the math.

    Let's play contrast-and-compare. If you want to leak a stream, you need:

    - A streaming account

    - Knowhow or software to decrypt the data stream as it's downloaded and played, or,

    - Knowhow to modify a TV so that you can capture the unencrypted video and audio streams inside the TV

    The last one isn't done because it's a pain in the ass and the TV scene prefers bit-perfect rips over re-encoded captures. But at some point in the TV, you have to decrypt the video; LCD panels do not natively accept encrypted signals. And that is something you can build hardware to capture.

    Now let's try leaking a movie. There's a few avenues of attack, roughly corresponding to the traditional movie scene release categories:

    - You can go to the theater and point a camera at the screen. They actually check for this now, in pretty much any western country you'll get kicked out or arrested for camming a movie. If you don't get caught, they can still narrow you down to a location in the room via your shooting angle, and possibly determine what theater you were at with line frequency hum. That's enough information to narrow down the guy leaking the movie to a handful of customers. Do this enough times and you create a unique fingerprint to catch yourself with.

    - You can get a job as a projectionist and run the movie projector into another camera directly. That kind of machine is called a telecine, and it used to be one of the higher quality ways to get leaked movies back when they were on film. This is specifically the scenario that all the DRM in the projector is designed to stop. If you do anything to change the light path of the projector, it locks up until the manager comes in and types a password to authorize the change.

    - You could bribe the manager or owner to telecine the movie for you. Problem is, the number of people who actually have the password that unlocks the projector is really small[2] and traceable. If a telecine leak is traced back to their theater, someone's getting fired at a minimum, jailed in the worst case.

    - You could break the DCI scheme itself; but you still need to source the files and keys to decrypt the movies. This is the crypto nerd's imaginary scenario. Even then, the files could themselves have steganographically injected information identifying the theater who got that master copy, which you can't strip out merely by having the encryption keys. Again, nobody is giving you those files unless they're too stupid to understand the implications (unlikely) or they have faith that you can strip out the stegotext.

    It's just way easier to rip a stream than a movie in a theater. And when Hollywood moved to streaming they also made it a lot easier to leak movies.

    [0] To be clear, traitor-tracing each stream would require a unique encode per account to inject the stegotext; that's computationally unfeasible. Doing one encode per movie theater would still be a struggle, but less so by three orders of magnitude.

    [1] https://xkcd.com/538/

    [2] This is also why the 3D era of film made movies way too fucking dark.

6stringmerc 4 hours ago

Fascinating read and I think an accessible presentation of a lot of the concepts / framework and mechanics of this type of system.