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Game of Thrones leak and watermark: a stupid tracking system

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Re: Game of Thrones leak and watermark: a stupid tracking system

#61

Post by madaxe_again »

fredley wrote: post #2

...or just use steganography. Steganography in videos can be made to be invisible to the naked eye, and extremely robust - even to video compression. It's also difficult to detect, and even more difficult to remove/tamper with. What the author of the article is proposing is actually a kind of steganography, albeit a rather crude one, and probably rather difficult to implement (since scene timings will be different fo…

While stego might be a route, blurring the watermark may not be enough to obscure the source.

Given a known frame, they could blur the same portion of the same frame on all watermarked copies, and the one with a matching output is your culprit.

Blurring loses information, but is more akin to a hash than a deletion, as it's a deterministic process.

Edit: this sort of thing. http://dheera.net/projects/blur

Re: Game of Thrones leak and watermark: a stupid tracking system

#62

Post by jjoonathan »

rlx0x wrote: post #54
fredley wrote: post #16

Earlier quoted context omitted.

To be honest, when I heard that the files were protected with a watermark, I assumed that they actually meant a steganographic watermark. I thought that this tech had been adopted into the industry ages ago, I'm rather surprised if it isn't the case, given the arms-race between the media and illegal distribution.

Your initial assumption was correct, it is widely deployed in the industry, there are multiple vendors that provide fingerprinting technology that is orders of magnitude more advanced then what the article suggests. The visible fingerprint might just have been there to deter the clueless. In any case even with a fingerprint its hard to proof without a doubt, the individual who actually stole it.

The visible fingerprint might also be there to prove intent or add circumvention charges in court.

I don't think they need to prove that a certain individual stole it. The party which received the advanced copies likely had to take on liability, so HBO can go after them. Of course, that doesn't mean they won't turn around and lean on the actual culprit, but whether or not they catch someone HBO will have their due.

Re: Game of Thrones leak and watermark: a stupid tracking system

#63

Post by damon_c »

How about a scheme where some selection of 16 shots throughout either are or aren't missing a single frame?

You could number 65k unique distributions that way and the overall length would rarely be affected by more than a frame or two.

It could be implemented with a pretty easy python script.

Re: Game of Thrones leak and watermark: a stupid tracking system

#64

Post by joezydeco »

intopieces wrote: post #50

Can someone help me understand the negative impact of this leak? From what I can tell, the leak only benefits HBO. Viewership numbers in the age of time-shifting are worthless. Moreover, viewers now cost HBO money, in terms of server load during the peak viewership time. If even a small number of people avoided the broadcast during the premiere, HBO actually wins - and there's no telling how many people decided to su…

Viewership numbers in the age of time-shifting are worthless

Do Comcast/TWC/DirecTV/Echostar feel that way? If even one person that was planning to subscribe to HBO over cable/satellite to watch this season decided to bail and watch the torrent instead, then the leak has economic impact. DVRs are irrelevant.

Re: Game of Thrones leak and watermark: a stupid tracking system

#66

Post by peeters »

madaxe_again wrote: post #61
fredley wrote: post #2

...or just use steganography. Steganography in videos can be made to be invisible to the naked eye, and extremely robust - even to video compression. It's also difficult to detect, and even more difficult to remove/tamper with. What the author of the article is proposing is actually a kind of steganography, albeit a rather crude one, and probably rather difficult to implement (since scene timings will be different fo…

While stego might be a route, blurring the watermark may not be enough to obscure the source. Given a known frame, they could blur the same portion of the same frame on all watermarked copies, and the one with a matching output is your culprit. Blurring loses information, but is more akin to a hash than a deletion, as it's a deterministic process. Edit: this sort of thing. http://dheera.net/projects/blur

It's a deterministic process, but it still has inputs. You'd have to know those inputs or test for every possible set of inputs to whatever blurring method was used.

Re: Game of Thrones leak and watermark: a stupid tracking system

#67

Post by jjoonathan »

URSpider94 wrote: post #43
markbnj wrote: post #32

Earlier quoted context omitted.

Came in to say this. It's the obvious answer, and presumably the IP owners know about it even if the author of the article does not. It's also obvious that the author doesn't understand video encoding if he is proposing measuring millisecond differences in the length of specific scenes.

This. The minimum difference in scene length allowable would be a single frame.

Do you actually know that or are you speculating?

I wouldn't be surprised if MP4 (or other video formats) provided a mechanism for tweaking the timing of a given frame. Of course, if you're using such a primitive watermark you might as well just add a note in the metadata...

Re: Game of Thrones leak and watermark: a stupid tracking system

#69

Post by avn2109 »

fredley wrote: post #16
llimllib wrote: post #10

Earlier quoted context omitted.

Of course we have no idea if they used steganography or not, right? He bases the article on the idea that they have no tracking info except the watermark, but I don't see any evidence that they don't know more.

To be honest, when I heard that the files were protected with a watermark, I assumed that they actually meant a steganographic watermark. I thought that this tech had been adopted into the industry ages ago, I'm rather surprised if it isn't the case, given the arms-race between the media and illegal distribution.

Arms race? The entertainment industry has cantered out onto the jousting pitch with their horse and lance. Meanwhile illegal distribution is calibrating the laser cannons in their orbital battle station and dispatching their aircraft carrier battle groups.

Re: Game of Thrones leak and watermark: a stupid tracking system

#70

Post by slayed0 »

xenophonf wrote: post #45

Anyone else here think HBO's missing out on a business opportunity? I wonder why they don't charge rabid fans (a _lot_) extra for early access to episodes. There appears to be a lot of demand for this.

Those episodes would immediately be leaked to everyone after becoming available and HBO would lose a ton of viewership on its own platform.
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