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Flood göndermek, insanların floodlarını okumak ve diğer insanlarla bağlantı kurmak için sosyal Floodlar ve Flood Yanıtları Motorumuza giriş yapın.

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3 ve kadim dostu 1 olan sj'yi rakamla giriniz. ( 31 )

Üzgünüz, Flood yazma yetkiniz yok, Flood girmek için giriş yapmalısınız.

Lütfen bu Floodun neden bildirilmesi gerektiğini düşündüğünüzü kısaca açıklayın.

Lütfen bu cevabın neden bildirilmesi gerektiğini kısaca açıklayın.

Please briefly explain why you feel this user should be reported.

Have we been ripping our DVDs wrong?

I recently came across the disc preservation project known as Redump. Many of you may already be familiar with it, but it is a digital archive containing tens of thousands of game discs for older consoles that would otherwise be lost. They are very particular about how they rip their discs, going so far as to publish their own disc dumping guides and to recommend specific disc drives. All in an attempt to create 1:1 bit-perfect copies, where every property of the original media is replicated, even mastering errors.

Compare that with improperly made ISOs found online, where the hash/checksum is wrong, or “trimmed” ROMs of games, which, despite being perfectly playable, are not archival quality.

All this made me more aware of how we rip copy-protected DVDs of films, some of which may be rare. Most Reddit threads and online guides recommend we just rip the disc with whatever program we have (DVD Decrypter, ImgBurn, PowerISO etc.) using default settings. But these programs don’t always produce the exact same ISO/MDS for a given disc. For example, DVD Decrypter by default removes region code, copy protection and prohibited user operations (PUOs) resulting in an ISO with a different hash/checksum compared to that of ImgBurn and PowerISO. Other programs may remove protection in different/non-standard ways, again resulting in different checksums. Everything that is removed from the ISO cannot be recovered unless we re-rip the original disc (which we may no longer have). It is worth noting that, despite the differences between ISOs, the actual movie files inside are identical.

So here are my questions:

-If our goal is disc preservation, and copy protection is inherently part of the disc, should we be removing it when ripping to ISO?

-What programs/settings would we have to use to get a perfect 1:1 copy of a disc i.e. the same file that the mastering facility used when producing the disc.

-Could this lead to problems when burning discs for playback?

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14 Yorumları

  1. I make perfect copies/iso’s of DVD’s by using ANYDVD HD to strip the CSS protection and then I just use any program that can make an iso out of a disc.

  2. I think you’re running into the chief issue with this sub of collectors vs archivists vs preservationists, which this sub has all three of, and you’ll get three different answers from. All are valid ofc

    If your goal is to ensure a 1:1 copy can be made in the future, then make a 1:1 copy. Perhaps its not as important on mass produced video games or DVDs, but this is and should be *the* standard for extremely rare titles. Especially games, where certain DRM may have an effect, positive or negative, on the title. If you only care for the content and not the physical medium, then perhaps removing the DRM would be fine, though tread lightly with software as it may have adverse effects.

  3. Take as example the preservation of a really old story: The Epic of Gilgamesh.

    We fortunately found the tables on which this story was written. And it is good to have it. But today, 4 thousand years later, we don’t need a 1:1 copy in their most original form. Nor do we want to read it in that way because that is, essentially, inaccessible. We use books, with translations.

    If having the original has its value, the preservation of the DVD is therefore interesting. And some people might be interested in knowing exactly how DVD technology was made. But what matters, really, is the creation.

  4. I agree that it would be good to standardize on a way to preserve DVDs in a way that two copies of it will have the same hash value, kind of like AccurateRip.

    Whether copy protection is preserved or not doesn’t make a difference to me. Just standardize on something.

    With that in place, there should also be a way to describe the contents of the DVD in a machine-readable text file (sidecar file) kind of like a .cue file for audio CDs, or like CDDB. The goal is for Plex or Kodi to play just the main feature and bypass the menus, FBI warning, etc. Basically remux on the fly to save space.

    Actually, this last goal might *require* copy protection to be defeated during the ripping process.

  5. So the drm would stay in place? Would this prevent you from playing it?

  6. So tldr you’re asking for Exact Audio Copy but for other disc formats?

  7. I’ve always backed up DVDs with ddrescue. (After authenticating disc to drive, as otherwise can’t read it). This results in a css encrypted iso that is bit for bit what was on disc (including intentionally bad sectors) but can be played normally with vlc which will brute force the css on demand.

    The only negative of brute forcing css is that small VOBs can’t be decrypted that way.

  8. I started working on a preservation project myself. I’ve been testing different methods for preserving different media.

    My results go like this. I use EAC – to preserve music cds to WAV format so the hashes don’t change up on me. MakeMKV for Blu-Rays (encrypted backups get the same results has Redumps MPF program the only thing you need to do is delete the discatt.dat) and then for DVDs I use MPF and extract the files from the ISOs.

    I create a datfile for my media and then I scan the files and they all get compressed.

  9. In my opinion, the act of removing the DRM is the preservation. I figure the DRM is “preserved” (if you want to call it that) in the tools we use to rip the discs.

  10. It’s an endless route. Now you are saying that we can get a perfect 1:1 copy of the digital data on the disc. What about near future, where we can copy molecules. By that time will you be interested in cloning the molecules or digitalize the molecules of a disc? Will you be focusing on what kind of plastic materials being used when producing the disc?

    You can of course preserve whatever you like, but the benefit of preserving certain things can be minimal. For example, DVD videos can be remuxed into MKV with all its content and meta data untouched. The benefit of preserving DVDISO is much less because there’s not much extra useful data to be preserved. Now that you are talking about “extra” data like CSS or DRM. Maybe the unwritten area of the disc can also be preserved so that you can burn the exact same garbage onto the disc. But does that really make sense?

  11. I’m not personally big on mainstream piracy, but I’ll never forget one time when DVDs were still the best format, some guy I worked with brought in one of those 300-disc binders and offered me anything I wanted to make a copy of. In there were about 300 burned DVDs, each with one mainstream movie on it, and *nothing else* – he’d stripped out all the menus, all the bonus features, all the commentaries, everything but the film. I’ll never forget how I felt like I was trapped in Plato’s cave and normal people were never going to understand me.

    Unfortunately, greed or anticapitalism, not a spirit of preservation, is the reason *anything* digital and popular has been preserved in any shape. That’s why it’s not done right, it’s just done to reproduce the most common desire (watching the main movie, patching the CD check and playing the game, listening to a lossy copy of an album at a quality level tolerable to the average person). When you find someone doing 1:1 ISOs of discs where it’s not the easiest option, you’ve found a preservationist.

  12. Imagine in 100 years stumbling across an amazing trove of digitally archived films, some thought lost or only existing in lesser quality.
    You spin one up only to discover that, since the human race has expanded to live in space, on Mars and around the asteroid belt, you are not in the appropriate region for playback.

    That’d suck.

    The purpose is to preserve things that are created. Only need to preserve the technology behind copy protection once, not on every disc.

  13. So the one thing I will say is that preserving the DRM / exact file structure for emulation is more important than for straight video.

    The copy protection and prohibited user operations and region codes don’t really need to be preserved because the video / audio is what you want to play back.

    Sometimes these things for video games do matter in how a disc is read or something the hardware needs to reproduce the game properly.

    If a game has slow down because of DRM / CPU limitations that should be reproduced. Having the option to fix / correct those is perfectly acceptable but the game is accurate when it runs exactly as it does on really hardware.

  14. > If our goal is disc preservation, and copy protection is inherently part of the disc, should we be removing it when ripping to ISO?

    I think the question is better framed as, what exactly are we trying to archive/preserve? Is it the actual content we’re interested in, or various implementations of CSS/AACS?

    I’d say that the content is the thing worth preserving, and treating various studio-required DRM as being worthy of inclusion in some future museum gives them far more credibility and cachet than they deserve.

    My personal opinion is that they’re tools designed to prevent me from doing what I want with things that I own, so fuck ’em 🙂