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Custos is using Bitcoin to turn digital pirates against each other

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Re: Custos is using Bitcoin to turn digital pirates against each other

#21

Post by plus »

If it is possible to strip the private key, e.g. by re-encoding, then an intelligent and determined leaker would simply do that before distribution. They likely won't be tempted to take the reward for themselves, given the consequences, and by stripping the private key they can prevent anyone else from claiming it. I suppose this would catch less savvy leakers, though.

Edit: To be clear, I understand that digital watermarking techniques can be resilient to a simple re-encode, but since Custos is providing the tool to claim the reward for free to pirates, it should be possible to reverse-engineer the tool to identify and destroy the watermark.

Re: Custos is using Bitcoin to turn digital pirates against each other

#22

Post by drewbuschhorn »

It's a great idea from a game theory perspective, but I think an adversarial neural network plugin built into vlc as a preencoding step would probably defeat it pretty quickly with minimal quality loss.

You just can't effectively watermark data intended for human consumption, our tolerance for intentionally induced noise is too high.

Re: Custos is using Bitcoin to turn digital pirates against each other

#24

Post by Blahah »

badosu wrote: post #2

> Custos embeds imperceptible bitcoin private keys in the digital files, with different keys for different advance copies of a movie or ebook. (...) > At the same time, Custos makes a piece of free software that screens movie files for these private keys and markets the screener to content pirates. Pirates now have an incentive to check pirated movie files in case they contain a key. If a key is detected, the pirate…

Seems pretty self-defeating. I'd just strip the keys and not claim the bounty. This whole system depends on pirates wanting $5 more than they want to pirate the thing, which from my 10 years around release and fxp groups in my younger days, I can say is barely ever the case.

Re: Custos is using Bitcoin to turn digital pirates against each other

#25

Post by philh »

pavel_lishin wrote: post #16
simias wrote: post #9

Earlier quoted context omitted.

You don't "report" to CustOS directly, rather you simply move the money from one of the CustOS "bounty" private keys into one of your own. Effectively it does the same thing but I think psychologically it's pretty different. For one thing you know that the bitcoin transaction will be very hard to trace (you can't be betrayed by your IP address or something like that) and you don't really rat anybody, you're just movi…

If I were a pirate/leaker/sharer, I would be very tempted to just paste the key on some completely unrelated forum to lay down a false trail.

What does that get you? If I understand correctly, I don't think the content owner finds out who uses the private key. They find out that the key has been used, which normally means that someone leaked the file to a pirate, and tells them who leaked.

Re: Custos is using Bitcoin to turn digital pirates against each other

#26

Post by Matt3o12_ »

borne0 wrote: post #20

I don't get it. Any 'damage' to the studio happens when the movie is publicly leaked, at that point just download the copy yourself and check for a watermark, telling you where the leak originated without ponying up $5-$10 (which is a paltry sum to begin with).

For this, the company has to first find the leak version. This means they need people to monitor all kind of sites for this material. With the bitcoin method, the company only needs to monitor a bunch of bitcoin wallets and, as soon as a transfer is made, the are aware of the leak immediately (with much less men power. Furthermore they also don’t need people who have access to those “private” torrent exchanges).

Furthermore, their response times are pretty awesome (if they are in fact true):

> Van Rooyen claims once a leaked copy containing a bounty hits the dark web, it takes just five minutes on average for the bounty to be claimed and Custos and its client to be alerted. On social networks it takes 42 seconds; and offline, like if a movie is copied or shared on a DVD or USB drive, it’s 28 minutes.

Re: Custos is using Bitcoin to turn digital pirates against each other

#27

Post by plus »

drewbuschhorn wrote: post #22

It's a great idea from a game theory perspective, but I think an adversarial neural network plugin built into vlc as a preencoding step would probably defeat it pretty quickly with minimal quality loss. You just can't effectively watermark data intended for human consumption, our tolerance for intentionally induced noise is too high.

I don't want to be confrontational, but I really don't understand the point you're trying to make. Why a neural network, why VLC? I understand that you are suggesting it would be possible to strip the watermark, but the way you've said it sounds a lot like "create a GUI interface using visual basic, see if I can track an IP address"[0]. Which is to say, you've not said what you would do to defeat it, but how you think it would be implemented... which doesn't really tell us anything about HOW you think it could be defeated.

>You just can't effectively watermark data intended for human consumption, our tolerance for intentionally induced noise is too high.

If this were true, steganography[1] would be useless in practice (it isn't).

I would suggest reading up on digital watermarking[2].

[0] https://www.youtube.com/watch?v=hkDD03yeLnU [1] https://en.wikipedia.org/wiki/Steganography [2] https://en.wikipedia.org/wiki/Digital_watermarking

Re: Custos is using Bitcoin to turn digital pirates against each other

#28

Post by philh »

borne0 wrote: post #20

I don't get it. Any 'damage' to the studio happens when the movie is publicly leaked, at that point just download the copy yourself and check for a watermark, telling you where the leak originated without ponying up $5-$10 (which is a paltry sum to begin with).

I was wondering about that. I had two thoughts, neither of which I'm confident is very significant:

- Finding and downloading the file is more work than just monitoring a set of bitcoin wallets. If the file gets leaked multiple times, and some of them end up in more obscure places, it might be much harder to find them.

- The regular watermark can perhaps be defeated by tech-savvy pirates, but the bitcoin watermark would need the leaker to be tech-savvy. I think leakers are selected by the content owner, and not in general for their tech-savviness, so this might be pretty safe.

Re: Custos is using Bitcoin to turn digital pirates against each other

#29

Post by hellbanner »

badosu wrote: post #2

> Custos embeds imperceptible bitcoin private keys in the digital files, with different keys for different advance copies of a movie or ebook. (...) > At the same time, Custos makes a piece of free software that screens movie files for these private keys and markets the screener to content pirates. Pirates now have an incentive to check pirated movie files in case they contain a key. If a key is detected, the pirate…

Isn't this what watermarks have been doing for a while? Different theaters get different watermarks

https://www.sans.org/reading-room/whitepapers/detection/wate...

Re: Custos is using Bitcoin to turn digital pirates against each other

#30

Post by jakobegger »

pavel_lishin wrote: post #18
jakobegger wrote: post #5

The big disadvantage with this scheme is that the publisher needs to pay the reward in advance for every copy they want to protect. That‘s why the rewards can‘t be big. (The publisher could of course keep the private keys and redeem unclaimed rewards themselves after some time, only risking currency fluctuations)

How many advance copies do they send out? Paying a thousand dollars on advance copies of a big blockbuster estimated to earn millions is nothing.

According to the article "tens of thousands" of advance copies are sent out. So if you want the reward per leak to be $10, the cost would be hundreds of thousands of dollars. Maybe that's worth it to a studio, but it definitely is a significant junk of money.
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