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How encryption for Cinema Movies works

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Re: How encryption for Cinema Movies works

#31

Post by thaumasiotes »

kmeisthax wrote: post #12
ddtaylor wrote: post #5

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

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 pr…

> Problem is, the number of people who actually have the password that unlocks the projector is really small[2]

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

What is the relationship between these two things?

Re: How encryption for Cinema Movies works

#32

Post by Aurornis »

john01dav wrote: post #3

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.

Pirated copies of theatrical releases at the time of release are much more rare, though.

The value of protecting releases is extremely high in the narrow window of finalizing production and getting it into theaters or online launch platforms.

If there was no DRM and watermarking then these would be pirated constantly before release.

Re: How encryption for Cinema Movies works

#33

Post by Aurornis »

coppsilgold wrote: post #17
perryflynn wrote: post #10

Earlier quoted context omitted.

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

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 the method is particularly ingenious (one of the inputs is centrally stored entropy which the extractor references by trialing them all) then knowledge of the process alone may not be sufficient to obtain…

> 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.

The commercial software used to embed watermarks into the digital files is not readily available. It’s also much more advanced than putting an obvious logo on screen. There are techniques to embed signals into the video that survive some amount of compression and aren’t obvious to the viewer.

You can identify signals deep below the noise floor if they’re sufficiently low bandwidth and you know what you’re searching for. See GPS and its ability to work even though the signal is completely lost in the noise until you know what you’re searching for in the noise.

Re: How encryption for Cinema Movies works

#34

Post by kelnos »

codemiscreant wrote: post #24
john01dav wrote: post #3

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.

There is essentially zero piracy from these digital cinema releases. The pirate copies are generally from once it starts digitally streaming on one of the services including PPV, and when pirate copies exist earlier it is almost always someone with a camera in a theatre making a terrible quality screener. Piracy is inevitable, but in this case their model is much more robust that I would have predicted.

Not sure of the GP's core message there, but I think this is kinda the point: even with all this onerous encryption on the cinema releases, high-quality pirated copies still very quickly make it out.

So basically they have this very secure scheme for getting movies to theaters, but everything else is full of holes. Makes you wonder if all the effort and cost to secure the theater distribution chain is worth it. If you're going to allow playback on devices in "adversarial" hands (streaming, home physical media playback), it's going to be incredibly difficult to restrict copying. Tightening up the one instance where the hardware and people operating it have less incentive to pirate (and more incentive to not pirate, given the risk to their theater business) seems like wasted effort.

Certainly this does make the case of a theater-only-first release nearly impossible to pirate. But there aren't quite as many of those anymore, and all this DRM must be expensive, both in the hardware/software, and in the logistics. I guess they've found it's worth it, but... oof.

Re: How encryption for Cinema Movies works

#35

Post by userbinator »

Aurornis wrote: post #30
dherls wrote: post #28

I'm confused why it's encrypted as a JPEG image per frame instead of one AES encrypted video file. Since the same AES key is used for each frame it wouldn't add any additional security imo

I think JPEG 2000 is simply the chosen format for distribution of the video, not for security. JPEG 2000 has some interesting properties for very high quality video storage and transport where bandwidth is not a concern. The traditional encoded video formats we know are less preferred at this scale. JPEG 2000 is resource intensive, though. The decoding hardware is probably either GPU based or using an FPGA implantati…

It's definitely dedicated hardware JPEG2000 decoding.

Re: How encryption for Cinema Movies works

#36

Post by userbinator »

Animats wrote: post #19

JPEG 2000 for each frame? I wonder what they use for decompression. JPEG 2000 decompressors are really slow. Most couldn't keep up with frame rate without GPU support.

Dedicated hardware, not even regular GPUs. JPEG2000 decompression has a rather complex entropy decoding part which is not easily parallisable.

Re: How encryption for Cinema Movies works

#37

Post by kelnos »

tptacek wrote: post #29
codemiscreant wrote: post #24

Earlier quoted context omitted.

There is essentially zero piracy from these digital cinema releases. The pirate copies are generally from once it starts digitally streaming on one of the services including PPV, and when pirate copies exist earlier it is almost always someone with a camera in a theatre making a terrible quality screener. Piracy is inevitable, but in this case their model is much more robust that I would have predicted.

Most importantly, the industry concerns itself primarily with the new-release window; that high fidelity copies will eventually be widely available doesn't break the model.

I suppose this would help keep pirated copies from getting out before the theatrical release date (presumably theaters are given these digital releases at least days before their first projection date).

But it seems that more and more releases are straight-to-streaming, and/or sometimes simultaneous with the theatrical release. High-quality pirated copies often show up within a day of a streaming release. Sure, many are still theater-only for a week or more after initial release.

I get that a big part of their business model for some titles relies on theater ticket sales within the first days or at most weeks after release, but all this DRM just feels like an exhausting, expensive, ultimately-losing game for them. Especially when we consider how theater-going has declined over time, especially recently.

Re: How encryption for Cinema Movies works

#39

Post by kelnos »

eastbound wrote: post #6
ajsnigrutin wrote: post #4

Earlier quoted context omitted.

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).

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.

> For 15 years you let paid options progress. [...] then suddenly you don’t find piracy anywhere.

And then they completely ruined it with fragmentation. When all I need to watch everything I wanted to watch was three subscriptions (Netflix, Hulu, and HBO), I was totally fine with the ~$40/mo and reasonably-ok-UX offered.

But now it's a mess. I need subscriptions to 7 or 8 different services (which now each cost twice what they used to for an ad-free experience), and the experience is crap. Netflix no longer plays on my Linux/Firefox setup (same thing happened with HBO years ago), and their anti-password-sharing mis-features constantly trigger for me even though I don't share my Netflix password. The Android apps for most of them are glitchy and buggy, and Chromecast has somehow gotten less reliable over time.

The irony is that usually I would say more competition is a good thing. I suppose if we had lots of streaming services, but studios were required to license all their content under RAND terms to anyone who asks, we'd have real competition, and streamers would compete on the quality of their platform, lack of ads, etc., and not just on what titles they were lucky enough to be able to license.

I do agree that pirating became less popular for a while, but that golden age is over. The piracy scene seems stronger than ever these days.

Re: How encryption for Cinema Movies works

#40

Post by washadjeffmad »

thaumasiotes wrote: post #31
kmeisthax wrote: post #12

Earlier quoted context omitted.

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 pr…

> Problem is, the number of people who actually have the password that unlocks the projector is really small[2] > [2] This is also why the 3D era of film made movies way too fucking dark. What is the relationship between these two things?

Wondered that, too.

Assuming it's not a typo, guessing that 3D films needed some additional calibration that didn't happen because it was a hassle needing the manager to make and reapply the changes.

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