Game of Thrones leak and watermark: a stupid tracking system • Hacker News Board

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

#51

Post by royjacobs » Mon, Apr 13, 2015, 2:25 PM UTC

NoMoreNicksLeft wrote: post #5

Not very clever. Get two leaked copies, and mix them up. Use the credits from copy A, or hell, even chop off 11 milliseconds from them. Then mix and match scenes... even chop off a few ms from some randomly selected scenes. I bet you wouldn't even need the two copies.

Steganographic systems used for tracking screeners would have no problem identifying the two different sources you've used. They are robust against all sorts of attacks, timing changes and edits. Removing frames doesn't really affect this, since it's not doing dumb frame-by-frame matching. You'd have to degrade your audio and video to the point where they become unwatchable in order to remove the watermark.

Disclaimer: I used to work for one of the companies providing these systems.

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

#52

Post by asillystory » Mon, Apr 13, 2015, 2:26 PM UTC

gpmcadam wrote: post #24

> Apart from that I think that binge-watching the first > 4 episodes is a stupid idea that will make you ache > for a month waiting for the 5th episode ☺. For me, I find more enjoyment in binging shows than being drip-fed, I watched all 4 in a row and don't regret not waiting (besides I've waited 12 months I can wait a few more weeks for more.) But more importantly, my online activity means I'll probably be spoiled b…

Binging makes the pacing of slow shows way more tolerable.

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

#53

Post by smitherfield » Mon, Apr 13, 2015, 2:34 PM UTC

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…

HBO most certainly did not leak it themselves; they could have their copyright on the material invalidated for that.

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

#54

Post by rlx0x » Mon, Apr 13, 2015, 2:35 PM UTC

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.

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.

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

#55

Post by DanBC » Mon, Apr 13, 2015, 2:37 PM UTC

marquis wrote: post #17

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…

It it were a full-screen steganograph it would need to be subtle as to not interfere with viewing. So could that be combatted by re-compressing with another codec?

> it would need to be subtle as to not interfere with viewing

Pre-release screeners often have big ugly on-screen watermarks. Almost anything is better than a scrolling mid-screen line of text "PROPERTY OF STUDIO NAME DO NOT PIRATE THIS FILM".

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

#56

Post by strangecasts » Mon, Apr 13, 2015, 2:38 PM UTC

tempodox wrote: post #6

This must be one of those posts you only understand after you've been primed into some obscure context.

It helps to be familiar with steganography; the post is basically proposing to make a unique watermark in a video by changing the starting times of each scene, and the rest of the post is mostly math to figure out how much you'd need to alter it to let you identify a single leaker from a given number of people.

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

#57

Post by smitherfield » Mon, Apr 13, 2015, 2:39 PM UTC

smitherfield wrote: post #53

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…

HBO most certainly did not leak it themselves; they could have their copyright on the material invalidated for that.

To elaborate, intellectual property law is essentially "use it or lose it" - a company that does not defend its IP against unauthorized use is likely to have it invalidated. One that actively promotes unauthorized use is almost certain to.

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

#58

Post by bryanlarsen » Mon, Apr 13, 2015, 2:42 PM UTC

smitherfield wrote: post #57

smitherfield wrote: post #53

Earlier quoted context omitted.

HBO most certainly did not leak it themselves; they could have their copyright on the material invalidated for that.

To elaborate, intellectual property law is essentially "use it or lose it" - a company that does not defend its IP against unauthorized use is likely to have it invalidated. One that actively promotes unauthorized use is almost certain to.

"use it or lose it" is only a property of trademark laws, not copyright or other IP laws.

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

#59

Post by nelhage » Mon, Apr 13, 2015, 2:43 PM UTC

Why do we think the blur is sufficient? The blur loses information, but there are presumably a small number of watermarked versions, and a lot of frames. It's almost certainly possible for HBO to reverse-engineer the blur algorithm — I bet it's a stock option from a common tool — and then run it over all the originals and see which produces the best post-blur match.

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

#60

Post by nissimk » Mon, Apr 13, 2015, 2:44 PM UTC

asillystory wrote: post #52

gpmcadam wrote: post #24

> Apart from that I think that binge-watching the first > 4 episodes is a stupid idea that will make you ache > for a month waiting for the 5th episode ☺. For me, I find more enjoyment in binging shows than being drip-fed, I watched all 4 in a row and don't regret not waiting (besides I've waited 12 months I can wait a few more weeks for more.) But more importantly, my online activity means I'll probably be spoiled b…

Binging makes the pacing of slow shows way more tolerable.

Yes, I was wondering why they sent 4 episodes for review. Then I watched the first episode and I saw why...nothing is going to happen until the 4th episode. They've been teasing us with white walkers since season 1. And those dragons too...they were born in season 1 or 2 and they've hardly killed anyone yet.

I guess I'm a sucker for the never-ending suspense...best show on tv.