PDFS--Of the WotC Court Case

[darjr]

Its interesting that in all three cases, the embedded micro-ids did the job of identifying the culprits.

As noticed repeatedly lately, they are eliminating one of their best tools in hunting down these pirates by eliminating the legal channels through which to mark the pdfs.

There is the idea that once the secret of the hidden water mark gets out, the pirates would go after it, making them completely useless.

 

[xechnao]

There is the idea that once the secret of the hidden water mark gets out, the pirates would go after it, making them completely useless.

Couldn't they change the hiding places of the watermarks?

 

[MadLordOfMilk]

There is the idea that once the secret of the hidden water mark gets out, the pirates would go after it, making them completely useless.

I was about to say "well, yeah, but how the heck are they going to find it?". Then I realized you could probably just get two or three separate people to order it then compare the PDFs to find the differences... gotta love how we can do stuff like that (I'd imagine with ease) with digital media.

 

[darjr]

were these hidden water marks WotC tech? Or tech belonging to Paizo and DriveThru? Have all the water marks on those stores been compromised now?

 

[malraux]

I sure do wish the document was OCRed so I could easily cut and paste from it. Or that it were an OEF pdf....

 

[xechnao]

I was about to say "well, yeah, but how the heck are they going to find it?". Then I realized you could probably just get two or three separate people to order it then compare the PDFs to find the differences... gotta love how we can do stuff like that (I'd imagine with ease) with digital media.

What if you have some kind of algorithm that hides it to some different spot regarding the page number of the product? You would have to check page per page.

 

[JohnRTroy]

I was about to say "well, yeah, but how the heck are they going to find it?". Then I realized you could probably just get two or three separate people to order it then compare the PDFs to find the differences... gotta love how we can do stuff like that (I'd imagine with ease) with digital media.

Well, it could be very difficult depending on the stenography. And you could add random pixels to each one as well--akin to a "salt" (hashing term), to prevent you from removing the watermark. I don't think a simple file compare will find it that easily.

I doubt it's a simple "single pixel" despite the court statement, or just on a single page.

Watermarking is not fool-proof, but it will prevent "casual piracy", which might be all that matters. It's a lot easier to upload a file than it is to remove DRM or hidden watermarks.

I suspect WoTC pulled PDFs to strategize a better protection system though--after seeing the complaints I doubt this is a huge conspiracy theory. Whether that's a different format, going through their own store, or a better watermarking technique, remains to be seen.

 

[malraux]

Couldn't they change the hiding places of the watermarks?

Well, I know zilch about the PDF format, but I can say that it should be easy to get a computer to do a pixel by pixel search to find such differences.

 

[JohnRTroy]

I sure do wish the document was OCRed so I could easily cut and paste from it. Or that it were an OEF pdf....

Assuming you're talking about the court case documents...

I've seen other PACER documents that are in that format. I guess it depends if they send Word or WordPerfect files to the court, or if the court just scans the document.

FYI, feel free to pass these documents around--they are part of the public record, and aren't protected by copyright. So if somebody can run an OCR on them, feel free. (The cost to get them from PACER is just to pay for maintenance of the electronic repository.)

 

[xechnao]

Well, I know zilch about the PDF format, but I can say that it should be easy to get a computer to do a pixel by pixel search to find such differences.

Pixels of each page are more than 6 millions. Are PCs robust enough for this? Assuming software exists for the job.