From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([208.92.234.80] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1Rbc0h-0003Vl-1Q for garchives@archives.gentoo.org; Fri, 16 Dec 2011 17:55:55 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id A9DA921C27A; Fri, 16 Dec 2011 17:55:31 +0000 (UTC) Received: from mail-ey0-f181.google.com (mail-ey0-f181.google.com [209.85.215.181]) by pigeon.gentoo.org (Postfix) with ESMTP id A69D521C26B for ; Fri, 16 Dec 2011 17:53:54 +0000 (UTC) Received: by eaaj12 with SMTP id j12so3740972eaa.40 for ; Fri, 16 Dec 2011 09:53:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=ZMr+1xh4d/YxZskcY4Mgh8lned5ONYRuGtOEo19fDpI=; b=orppSXEvF9mLFM+CIn+ntM6bpI9q4fLEyxl8DY9t6zO36x+QLP4tXl8cA2XMrKyk4Z +TURWU+OJkfnemyivoit3k6AJMXLCrWT0qoUbER8vtXiTbUWI8SXBSLfxB6kF03KASBJ u96f+WmZ60WLwZu020vYqP62Nff/qF60R1fFk= Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Received: by 10.204.156.216 with SMTP id y24mr3211224bkw.80.1324058033862; Fri, 16 Dec 2011 09:53:53 -0800 (PST) Received: by 10.204.226.72 with HTTP; Fri, 16 Dec 2011 09:53:53 -0800 (PST) In-Reply-To: References: Date: Fri, 16 Dec 2011 12:53:53 -0500 Message-ID: Subject: Re: [gentoo-user] DVD Movie backups From: Michael Mol To: gentoo-user@lists.gentoo.org Content-Type: text/plain; charset=UTF-8 X-Archives-Salt: cc3fc82b-0f25-4ccb-8840-278a1a4a5ea2 X-Archives-Hash: 12d49304a739834df944c770406a78c5 On Fri, Dec 16, 2011 at 12:25 PM, Mark Knecht wrote: > On Fri, Dec 16, 2011 at 9:06 AM, Michael Mol wrote: >> No; you'll have to decrypt, or do without the encrypted bits. >> >> dvdbackup is probably the closest to what you want. >> >> On Dec 16, 2011 11:09 AM, "Mark Knecht" wrote: >>> >>> For archive purposes is there a simple way for me to make a >>> bit-for-bit copy retail DVDs I've purchased? >>> >>> Assume that I've got the right sort of DVD drive, I guess something >>> capable of writing dual-layer DVDs. >>> >>> Thanks, >>> Mark > > Interesting. So even something that just copies blocks of data, like > dd, can't be used for that purpose? > > I have no interest in tearing apart the DVD in any way. It was more > about the idea of a fire causing the loss of maybe $15K-$20K > investment over the years. I can rip all the CDs, keep the ripped > version here to watch on the computer, and store the DVDs elsewhere, > but that elimiates (generally) being able to watch special features > which my wife and kid enjoy. > > Thanks for the info. I did exactly the same thing a few years ago, but it's been a long, long time, so my memory on my process is very fuzzy. (It also involved my first foray into RAID...I've got a couple hundred DVDs!) Go ahead, count the number of times I qualify something with "IIRC"... dvdbackup can recreate the ISO images, IIRC. If you run a simple 'dd' on a DVD with encrypted portions, you'll get I/O errors when it encounters the encrypted pieces. IIRC, some of the data required to decrypt those portions is on the disc, but it's in an out-of-the-way portion that won't show up as part of the block device. IIRC, dvdbackup makes use of libdvdcss to decrypt the encrypted portions[1], and writes a decrypted version of the data. *this* is why you can't make a bit-for-bit copy; the output data would be decrypted. There are other, later obstacles, too; once CSS was broken, some content publishers (Bandai USA, for example) would fudge the ISO spec and the DVD nav specs in ways that didn't break *most* hardware DVD players, but did tend to break players which strictly adhered to the standards, such as ffmpeg, vlc and mplayer. It also broke dvdbackup for me, IIRC, which is why I had to resort to vobcopy in some cases. I expect the software angle for handling these things has gotten better, though. [1] I don't know how it does it when dd would have hit an I/O error. Obviously, my understanding of the workings of dvdbackup, dd, DVDs and CSS encryption is flawed somehow. -- :wq