[Liverpool] Backing up video DVD's

[Graeme Dyas]

If I recall correctly backing up a DVD is
not illegal hoever decrypting/breaking the copy protection is.

On 3 June 2011 11:18, Stephen Watkin <ste at enzy.me.uk> wrote:

> The last time I was tasked with backing up a DVD, it turned out the disc in
> question was purposefully corrupted in places to throw off straight-forward
> attempts at duplication. It was quite a while ago, but I remember the
> solution involved downloading some file containing an index of all the
> broken sectors to avoid that was specifically for that disc, then feed it to
> some (windows) program that copied the disc in such a way as to avoid those
> sectors.
>
> As it happens it wasn't even for my own selfish gain that time. It was a
> friend's Barney The Dinosaur DVD that he bought to replace the one his kid
> scratched to bits. He wanted a copy so he could keep the original safe. I
> don't even know if we're even legally allowed to make backups in this
> country.
>
> Ste
>
>
>
> On 03/06/11 10:16, Sebastian Arcus wrote:
>
>> Following on from the conversation the other night regarding backing up
>> video dvd's, I went back and did more experiments.
>>
>> 1. cp and dd will work on dvd's without copy protection.
>> 2. dd will work on some copy protected dvd's - if used with "bs=1024" as
>> an option.
>> 3. However, both cp and dd will fail (sometimes after about apparently
>> random amounts of data - on some dvd's as much as 298MB) on dvd's with
>> certain copy protection systems. The failure is different from film to film,
>> but the amount of data copied before failure is always the same on different
>> tries for the same disc. In my case only about 25% of dvd discs I tried
>> could be copied with dd or cp.
>> 4. vobcopy will manage most copy protection systems - but I still have
>> about 1% of my brand new dvd's which have played just fine on the same
>> computer - but vobcopy hasn't managed to copy. I've seen other reports on
>> the internet that there are several copy protection types which give
>> problems even to vobcopy. Maybe it will be fixed in a future version. The
>> symptom seems to be caused by a trick in the layout, where the drive is
>> stuck in what sounds like repeated seek action on the disc - in a permanent
>> limbo - while copying under vobcopy.
>>
>> I'm using vobcopy 1.2.0. I'm not sure how would one find out which copy
>> protection system a particular dvd is using. I've seen talk on the Internet
>> about several different types - but nobody mentioned how to find out what is
>> used on a particular disc.
>>
>> I would be curious if others have found otherwise on their machines or
>> their dvd's
>>
>> Sebastian
>>
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>
>
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