Re: [tlug] Re: MPEG stream analyser?

[Josh Glover <jmglov@example.com>]

On Tue, 22 Mar 2005 11:35:32 +0100, Tobias Diedrich <ranma@example.com> wrote:

> Well, AFAIK simply decrypting the DVD with decss and then
> regenerating the iso with mkisofs and burning it onto a DVD-R will
> defeat the region code scheme,

Right. Of course, it gets a bit more complicated when you are backing
up a dual-layer DVD onto single-layer media.

In any case, I know how to do DVD backup. The question that I have
asked in this thread is simply whether a tool exists to analyse an
MPEG file and show me data on the individual streams.

> (DVDs contain some sort of
> bytecode interleaved with the video, which is used for menus among
> other interactive DVD-Features.[)]

I do not think that is how it works. Menus are accomplished with
sub-picture streams (that is the same way that subtitles are
implemented), and the navigation is written into the table of
contents, AFAIK.

> Since one of the player registers contains the region code it is possible to check 
> against it and refuse to play if it doesn't match).

This is possible, except that I have never seen a player that is not a
game console that will not play unencrypted DVDs (the PS2 refuses as
an anti-piracy measure), since it is completely legitimate for a movie
studio to produce one such disc. Every once in awhile, I find a
Hollywood movie in my collection that is not encrypted. Many
non-Hollywood discs are not encrypted, notably in my collection:
"Revolution OS". [1]

> But at least for Backups this
> should be a viable way, as long as the DVD-Content fits onto one
> DVD, but with the advent of dual-layer DVD-R this shouldn't be a big
> problem any longer.

Can you afford dual-layer media? I sure cannot. Compare roughly US$
0.40 for a single-layer, DVD+ or -R disc to US$ 8.00 or so for a
dual-layer DVD!

> I guess we might not get as lucky with the next-generation video
> format (HD-DVD?).  OTOH, since the vast majority of people won't care
> about being locked into their region, maybe they won't make it too
> difficult for the modders.

I do not see how any technical advance is going to change things much.
The greedy media conglomerates come up with some half-assed
"anti-piracy" (read: anti-consumer) scheme, which DVD-Jon or some
other enterprising hacker breaks in a month. Like Dr. Turnbull said,
copy-protection is to stop Joe User, not Bob the Audiophile, who
*will* find a way to play his music his way.

Anyway, bottom line is that I am going to have to hack up a stream analyser.

Cheers,
Josh

[1] http://www.revolution-os.com/