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Work Around for New DVD Format Protections
An anonymous reader writes "For the new Blu-ray and HD-DVD formats, Hollywood implemented a complete copy protection scheme; almost everything has to be encrypted and authenticated. Despite the crypto-stuff in Advanced Access Content System and High Bandwidth Digital Content Protection, they left the backdoor wide open — they forgot about the PrintScreen button. Using this function you can create exact digital copies of a film picture-by-picture and reassemble them into a stream."
This doesn't work well even with regular DVDs. Ever think of Macrovision?
English is easier said than done.
If you really want to copy a blue-ray movie, there are easier ways, such as decrypting HDCP.
Whatever happened to the "I bought the DVD, I should do what the fuck I want with it"?
+5, Truth
Plus, what's the point of going back two generations? Sure, you could watch the movie, but you're not getting a high definition picture anymore... So why not make a copy of the regular DVD, which as we know are easy to rip/decrypt. Otherwise, it would be like going from a CD to an 8 track. And I don't think there's too many people out there doing that.
30 frames/sec * 60 seconds/minute * 150 minute movie = 135000 pictures, no? That's an awful lot of times pushing the print screen button. Even if you can "print" to an image file, and use a script to "push" the button continuously, once you factor in reassembling it, that'll still take a while.
Do you really think that no one will write a quick script to do this automatically???
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i.e.
Function: abbreviation
Etymology: Latin id est
that is
e.g.
Function: abbreviation
Etymology: Latin exempli gratia
for example
You never did have the right to do what the fuck you want with it. You never were allowed to copy it and sell it. You never were allowed to charge people to see it. You never were allowed to rip it and upload it to random others whom you don't know.
What you have had the right to do is view it for your own private entertainment, to loan the disc to a friend, and to give away or sell the disc provided that you don't keep any copies of it. What you should have the right to do is make a backup copy for safekeeping, or for viewing on a device that doesn't have a DVD drive/player (notebook PC, iPod, whatever).
disable video acceleration in the player settings and you can screen cap from any video player software,
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There will be an image quality degradation since it's the decompressed stream that is being copied, and it will have to be recompressed to get it back to a size that will fit on HD-DVD/Blu-Ray. Therefore, this isn't equivalent to a direct copy of the compressed data stream.
I'm surprised that they haven't disabled the print-screen functionality in some way so that it's not possible to do this.
For example, in OS X, taking screenshots is disabled whenever DVD Player is running. It's not particularly hard to get around (actually, it's almost trivially easy; yet another situation where I feel like Apple did just the bare minimum required to look like they care) using the Terminal or a third-party applet that calls the screen grab, but the normal hotkey is disabled.
I assume that if this method becomes a popular way of ripping movies, that the ability to take screenshots on Windows will simply be similarly crippled (probably more thoroughly), or removed altogether under certain situations. ('Printscreen doesn't function unless conditions x, y, and z exist...')
That's not to say that I ever think it will be impossible for a sufficiently motivated person to rip a movie (or indeed, circumvent any level of DRM), but that a simple-but-useful historical feature like Print Screen could easily become a casualty of the DRM war.
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You can't create an "exact digital copy" via this method unless you store the file in an uncompressed format
May I add that, even if you did the above, it would still not be exact in many cases, since screenshots are usually taken after the player has filtered the video (brightness/colour adjustments, deinterlacing, etc.), so you'd see a lot of irritating variability between different rips. Someone who downloads an unauthorised copy for free may not care so much, but it'd hardly be ideal for things like personal backups of your discs.
In which case you could still use a virtualization tool to virtualize the video-playback OS, and then grab the screenshots from that.
Isn't this the point of having DRM hardware? My understanding is:
1. Read encrypted content off bluray disc
2. The media player software decrypts the content and shoves it at the display driver with a "DRM flag" set
3. The display driver encrypts it and sends it to the graphics card
4. The graphics card decrypts it, re-encrypts it with HDCP and shoves it at the monitor
5. The monitor decrypts it and displays it.
So the weak points are the media player, the display driver and the monitor.
If you ran it inside a VM then you would either have to emulate the graphics card (almost impossible because you'd need the graphics card's encryption keys to convince the driver to talk to you) or let it talk to a real graphics card and intercept the stream (which would be encrypted, so completely useless).
The assumptions the industry is making are basically:
1. The media player is trusted since only trusted players can licence the bluray decryption keys (we saw how well that worked with DVDs - I play them regularly on Xine)
2. The display driver is trusted - this might be the case if you only trust signed drivers.
3. The monitor is trusted to not have a "decrypted output"
In any case, the easy way to grab bluray content at the moment is to decrypt the HDCP stream, since HDCP has already been cracked. I don't hold out much hope for the media players remaining trusted for too long - putting any kind of DRM system in the hands of a large number of suitably motivated techies is going to result in it being cracked reasonably quickly.
Until bluray/hddvd has been cracked there's no way I'll be buying movies in those formats anyway - DRM is fundamentally incompatable with FOSS media players, and if the MPAA thinks I'll be putting any closed source software from them on my system they're very mistaken - after things like the Sony incident I really wouldn't trust software from that industry unless it could be audited by the public. (Not to mention that I have no HDCP capable hardware and have no intention of buying any any time soon).
http://blog.nexusuk.org
It takes about 1/10 of a second for me to hit print screen and paste the picture into Paint The screenshot resolution is 2560x1024. The blink in the cursor when the image is being copied is barely noticable. This is with a Intel Core Duo based system.
That's all irrelevant though; if the image can be accessed so that print screen can put a copy in the clipboard, a program can access that image in memory and feed it into the video encoder directly.
THE HELL THEY DO! The only reason the laws "protecting" their closed format exist is to promote innovation in progress. Closed formats impede progress, therefore "IP" laws cannot (either Constitutionally or morally) protect closed formats!
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But then your locked-down "Trusted [sic]" system will simply refuse to run your unsigned code, and you'll be back at square one (and if your system isn't "Trusted [sic]", the HD player software and/or the drive itself will refuse to decrypt the movie to begin with).
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz