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How encryption for Cinema Movies works

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Re: How encryption for Cinema Movies works

#71

Post by abujazar »

loeg wrote: post #46
plastic3169 wrote: post #44

Earlier quoted context omitted.

There are no high quality pirated versions though. The streaming version and even blu-ray is compressed way heavier than these DCP files. I’d buy these cinema versions of films in a heartbeat if they were availble.

1080p/4k as encoded by the streaming sites / blu-ray is sufficiently high quality for virtually all of the viewing public. You're weird (no offense).

As someone who's been working with cinema and video mastering, it sounds like you haven't seen the difference between professional formats like DCP and consumer formats viewed on a proper screen or projector. There's a reason we still have cinemas after all.

Even consumer equipment benefits greatly from visually lossless encoded media.

Re: How encryption for Cinema Movies works

#72

Post by jackjeff »

perryflynn wrote: post #66
jackjeff wrote: post #59

> The video stream is encoded as one single JPEG2000 picture per frame. Each frame is encrypted with the same static AES key. Is this not a problem? It’s not a good idea to reuse the same key to encrypt very similar files. Similar to ECB. See the famous penguin https://words.filippo.io/the-ecb-penguin/ I’m surprised they don’t use something like XTS commonly used for disk encryption. It derives a unique key for each…

No. They use a unique IV for each frame: > Every Frame is using a unique IV (Initialization Vector), which ensures that the AES Block Cipher generates always different cipher texts and makes brute force harder. This works similar to a Password Salt.

Oh thanks. I missed that. I guess that works pretty well too!

Re: How encryption for Cinema Movies works

#73

Post by geraldwhen »

abujazar wrote: post #71
loeg wrote: post #46

Earlier quoted context omitted.

1080p/4k as encoded by the streaming sites / blu-ray is sufficiently high quality for virtually all of the viewing public. You're weird (no offense).

As someone who's been working with cinema and video mastering, it sounds like you haven't seen the difference between professional formats like DCP and consumer formats viewed on a proper screen or projector. There's a reason we still have cinemas after all. Even consumer equipment benefits greatly from visually lossless encoded media.

No one goes to the theater because the picture is better. It often isn’t.

Projectors aren’t maintained, or set up correctly, and audio balancing is often way off. People go to the movies to see new releases or have dedicated shared experiences

Re: How encryption for Cinema Movies works

#74

Post by jdright »

jasode wrote: post #68
kelnos wrote: post #34

Earlier quoted context omitted.

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 yo…

>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. Kaleidescape movie players[1][2] are an example of an "adversarial" environment in customers' homes but so far, their DRM is still unbroken by pirates. (10+ years of Strato players deployed out in the wild but still not defeated yet.) The 4k 100+ GB…

That is a ridiculous statement. Nobody would even care to break this thing. Look at it's base price, then lookat their customers. It makes no sense to break it.

Re: How encryption for Cinema Movies works

#75

Post by kevinmchugh »

geraldwhen wrote: post #73
abujazar wrote: post #71

Earlier quoted context omitted.

As someone who's been working with cinema and video mastering, it sounds like you haven't seen the difference between professional formats like DCP and consumer formats viewed on a proper screen or projector. There's a reason we still have cinemas after all. Even consumer equipment benefits greatly from visually lossless encoded media.

No one goes to the theater because the picture is better. It often isn’t. Projectors aren’t maintained, or set up correctly, and audio balancing is often way off. People go to the movies to see new releases or have dedicated shared experiences

I am absolutely seeing mission impossible in theaters next month because their screens and speakers are better.

Re: How encryption for Cinema Movies works

#76

Post by Mindwipe »

kelnos wrote: post #37
tptacek wrote: post #29

Earlier quoted context omitted.

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…

> But it seems that more and more releases are straight-to-streaming, and/or sometimes simultaneous with the theatrical release

If anything, it's less and less. Studios are pulling the PVOD date further and further out for successful titles generally (Universal excepted). All the talk from Cinemacon was going back to a 60 day+ exclusive theatrical window.

Re: How encryption for Cinema Movies works

#77

Post by Mindwipe »

ajsnigrutin wrote: post #11
eastbound wrote: post #6

Earlier quoted context omitted.

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.

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 t…

> Yes, and those paid options were one subscription that had "everything".

It really didn't. It's incredible this collective delusion exists when it's not true.

Re: How encryption for Cinema Movies works

#78

Post by Aurornis »

userbinator wrote: post #36
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.

The parallel part would come from batch decoding upcoming frames across multiple cores and buffering the result.

4K at 90fps decoding is easy for commercial decoders with a consumer GPU. The dedicated hardware solutions are out there but they’re not the only way to do it any more.

Re: How encryption for Cinema Movies works

#79

Post by jasode »

jdright wrote: post #74
jasode wrote: post #68

Earlier quoted context omitted.

>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. Kaleidescape movie players[1][2] are an example of an "adversarial" environment in customers' homes but so far, their DRM is still unbroken by pirates. (10+ years of Strato players deployed out in the wild but still not defeated yet.) The 4k 100+ GB…

That is a ridiculous statement. Nobody would even care to break this thing. Look at it's base price, then lookat their customers. It makes no sense to break it.

>Look at it's base price, then lookat their customers. It makes no sense to break it.

You're not thinking the same way the motivated pirates think. Some pirates (especially in Eastern Europe, Asia, etc) rip new releases as fast as possible to illegally re-sell or re-stream for lower prices (or show along with ads for revenue). In this way, the pirates get the revenue instead of the legitimate movie studios.

So pirate groups in combination with illegal streaming websites can be thought of as a black market financial arbitrage. So far, the video sources they used include Blu-Ray rips and streaming Netflix or Amazon Prime Video webrips.

However, the Kaleidescope players could theoretically also be included as rip sources ... if the DRM was broken. The math for profitable arbitrage isn't that ridiculous. E.g. :

- a 4k UHD Blu-Ray is $33.49 : https://www.amazon.com/Conclave-4K-UHD-Edward-Berger/dp/B0DP...

- it would take only ~80 of those titles to recoup the cost of $1995 Kaleidescope player + the $7.95 rental fees for 80 downloads. All downloads after that break-even threshold is extra money for the pirates. Another bonus is pirating 4k UHD content that's not available on physical Blu-rays.

But the Kaleidescope DRM isn't broken. Therefore, the $7.95 rental downloads can't be used as a new vector for pirate releases. Of course, Kaleidescape doesn't want this scenario to happen so they're incentivized to continue paying for the DRM licensing protection.

And to recap the specifics I was replying to, it was this: >"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."

Kaleidescape is one counterexample to that. So far, they have actually restricted copying with success.

Re: How encryption for Cinema Movies works

#80

Post by yladiz »

anal_reactor wrote: post #67
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.

Most people are completely fine watching a 720p x264 1GB version half a year after release. Sure, there are some purists who want as good image quality as possible as soon as possible, but that's a tiny minority. I think the actual motivation is that cinemas are becoming less and less relevant in the age of streaming, so they're doing anything they can to protect the little revenue they have, because the only way cin…

This really downplays the cinema experience. Yes, many people are fine watching a movie at home while doing something else (the current Netflix model of filmmaking is precipitated on this), and others are fine to watch at home in general, but few people would truly say that their setup is close to what you get in a cinema. The screen is much bigger, the image quality is higher, and the sound system is much better as well, compared to anything short of an actual home cinema setup. It’s not the only reason of course, but it’s one of a few reasons cinemas still sell out for big films like Dune 2, and why people will go out of their way to go watch it in the cinema.

Streaming will never fully replace cinemas, even if it dramatically impacts their operating mode, and to argue otherwise is naive.

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