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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

#41

Post by dragonwriter »

plus wrote: post #21

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 wat…

Reading data out of an enclosed file is much less of a problem than altering that data without damaging the file. All you need for “screening” and “claiming” is to read out the keys and check if the funds have already been transferred out on the blockchain and, if not, transfer them out. There's no alteration to the file content involved.

Destroying the keys requires altering the file while leaving it functional, which requires more than reverse engineering the tool, because the tool doesn't need that capacity.

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

#42

Post by Adverblessly »

Maybe I don't understand something?

John Doe, random employee working for Universal Studios leaks an advance copy of "The Revenge of the Avengers: The Revengers Strike Back" to their contact XPirateSepirothX for 250$ (or for free because they really want to get back at their boss for laughing at them).

XPirateSephirothX passes on the watermarked movie to their friendly neighbourhood reencoder IAmBecomeDeath who notices the watermark strips it, and reencodes the movie for general consumption.

The pirating public receives an unwatermarked copy and cannot claim any prize. IAmBecomeDeath, XPirateSephirothX and John Doe have no incentive to claim the prize because they will implicate themselves in copyright violation.

Are they implying the watermark is impossible to remove? That seems unlikely to me as pirates can be quite enterprising (and there may be some money on the line for them as well), so I'd expect them to reverse engineer the process and figure out how to strip it. Heck, this company is even offering an application that checks if the watermark is present or not which should at least give the pirates a measurement on whether their watermark removal method worked (on at least some version of the watermark detection logic).

Or maybe the plan is to play a constant game of cat and mouse, Custos will continually switch up their methods for watermarking and so the pirates will never be sure if they caught and successfully stripped the latest and greatest version of the watermark, preventing some piracy through uncaught watermarks and some piracy through fear?

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

#43

Post by dragonwriter »

tuxxy wrote: post #6

This is neat, but I can't help but feel it's not going to work. It would work if you encounter a movie that you wanted to watch, decide you want the money instead, and you report to Custos. This is not how piracy works. Instead, a pirate knows the value of the good they have. They know it's worth more to their reputation in the community than $5-10 dollars. By setting a bounty on it, you'll just have others willing t…

> It would work if you encounter a movie that you wanted to watch, decide you want the money instead, and you report to Custos.

What do you mean “instead”; draining the Bitcoin wallet identified in the bounty watermark doesn't make your copy (or any identical copy) stop working, it just let's Custos know (by reading the blockchain) that the original from which it was copied had the corresponding Bitcoin wallet drained.

There may be a trade-off about future content from the same root source, but not the current piece of content.

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

#44

Post by anilgulecha »

Adverblessly wrote: post #42

Maybe I don't understand something? John Doe, random employee working for Universal Studios leaks an advance copy of "The Revenge of the Avengers: The Revengers Strike Back" to their contact XPirateSepirothX for 250$ (or for free because they really want to get back at their boss for laughing at them). XPirateSephirothX passes on the watermarked movie to their friendly neighbourhood reencoder IAmBecomeDeath who notic…

> IAmBecomeDeath who notices the watermark strips it, and reencodes the movie for general consumption.

Or wants the $$, so claims it, putting down a breadcrumb. (Atleast that's what the technology in the article is for.)

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

#45

Post by icebraining »

anotheryou wrote: post #37

I see no advantage over traditional invisiblee watermarks. A movie usually just leaks once or twice, these leaks get replicate everywhere. So if you are looking for a specific movie, just get a pirated copy from anywhere and check the watermark yourself. It's trivial to check if there is a leak at all and also trivial to find that leaked version and test it. No need to throw 15 bucks per copy on it, just let the inte…

I think the difference is that the person who spreads the movie over the trackers, who is not necessarily the original leaker, now has an incentive to report it, whereas with regular watermarks they'd simply remove it before distributing over those public channels.

Of course, it's hard to see such person being in a position to receive many leaks in the future, after burning the original leaker, so the incentive seems quite small.

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

#46

Post by plus »

dragonwriter wrote: post #41
plus wrote: post #21

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 wat…

Reading data out of an enclosed file is much less of a problem than altering that data without damaging the file. All you need for “screening” and “claiming” is to read out the keys and check if the funds have already been transferred out on the blockchain and, if not, transfer them out. There's no alteration to the file content involved. Destroying the keys requires altering the file while leaving it functional, whi…

My point is that if you can identify how the private key is stored in the video, then it should be possible to develop a strategy to destroy that data without damaging the integrity of the file. Presumably the key will be hidden in such a way that it won't be obvious to viewers (that is, it won't be a literal watermark). If that's true, then it should be possible to destroy the key without making the video quality noticeably worse, e.g. by selectively re-encoding certain parts of the video in a certain way that ensures destruction of the private key. Of course I'm speculating, because I don't know exactly how the private key is stored in the video, but video quality is a lot more robust to bit massaging than a hidden digital private key would be.

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

#47

Post by icebraining »

Adverblessly wrote: post #42

Maybe I don't understand something? John Doe, random employee working for Universal Studios leaks an advance copy of "The Revenge of the Avengers: The Revengers Strike Back" to their contact XPirateSepirothX for 250$ (or for free because they really want to get back at their boss for laughing at them). XPirateSephirothX passes on the watermarked movie to their friendly neighbourhood reencoder IAmBecomeDeath who notic…

The idea is that IAmBecomeDeath and XPirateSephirothX are not implicated, since they can claim it anonymously, by simply moving the coins to a random BTC address, and then using a tumbler or something to cover their tracks.

Of course, John Doe and whoever knows about this will never trust them again to spread leaked copies, so it's hard to see $5 being worth that loss.

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

#48

Post by [deleted] »

Adverblessly wrote: post #42

Maybe I don't understand something? John Doe, random employee working for Universal Studios leaks an advance copy of "The Revenge of the Avengers: The Revengers Strike Back" to their contact XPirateSepirothX for 250$ (or for free because they really want to get back at their boss for laughing at them). XPirateSephirothX passes on the watermarked movie to their friendly neighbourhood reencoder IAmBecomeDeath who notic…

[deleted]

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

#49

Post by drewbuschhorn »

plus wrote: post #27
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 thin…

> I don't intend to be confrontational

Of course you do, or you wouldn't end the comment with "I suggest you read up on."

Stenography is only useful when it's unknown or impractical to investigate possible payloads, either do to volume of possible hits or lack of knowledge how to decode the payload out of the source. If you tell an opponent: here is the decode technique and here is where the message is likely to be, you've basically defeated your own stenography.

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

#50

Post by plus »

drewbuschhorn wrote: post #49
plus wrote: post #27

Earlier quoted context omitted.

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 thin…

> I don't intend to be confrontational Of course you do, or you wouldn't end the comment with "I suggest you read up on." Stenography is only useful when it's unknown or impractical to investigate possible payloads, either do to volume of possible hits or lack of knowledge how to decode the payload out of the source. If you tell an opponent: here is the decode technique and here is where the message is likely to be,…

It is true that my intention was not to be rude. My "I suggest you read up on" comment was in response to your claim:

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

Which is simply not true! That kind of misunderstanding suggests that you are unfamiliar with the kinds of digital watermarking that are used TODAY, hence my suggestion that you read up on it. If the comment came off as rude, I certainly apologize, but I stand by the point I was trying to make.

>If you tell an opponent: here is the decode technique and here is where the message is likely to be, you've basically defeated your own stenography.

I agree with you on this point 100%. I also made a post to that effect elsewhere. But that is not the same argument you made in your previous post!

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