1:1 copy question

nanok66 2005-08-13 10:06:04 UTC #1

Hello, I just read this article on dvd compatibility - http://www.cdfreaks.com/article/150 but the article still leaves a question in my mind about 1:1 copies. Here is the excerpt I'm talking about:

"During the production of a DVD-R disc the lead-in is pre-embossed (pre-written). This overwrites parts of the DVD that contains information about the disc. E.g. the CSS key (part of the copy protection) is in this part on commercial movie discs (This is why you canâ€™t make a 1:1 copy of a DVD)."

I dont understand this, if factory dvd burners can burn onto certain parts of a disc then why cant consumer burners do the same?? Why cant our plextors or lite ons burn the lead-ins as well? I may be out in left field on this but the only reason I could fathom would be if it's an industry law not to give consumers the ability to burn as well as the producers. Because otherwise what is to stop any company from making the 'perfect burner'? Please explain!

Bob_the_bored 2005-08-13 10:38:13 UTC #2

It's a different system to write DVDs at home compared to industrial methods, if you were to buy industrial blanks and an industrial writer then you could. The CSS write area bit is quite probably done that way to prevent 1:1 copies. However the standard for home useable DVDs is set and no one will make DVDs that intentionally fail to work (except bulqpaq)

Juggernaut 2005-08-13 19:02:55 UTC #3

If I'm not mistaken, comercial DVDs are "pressed" from a master disk. Burning millions of DVDs would take far to long. DVD burner manufacturers probably could make 1:1 copies possible but won't because it would violate the -r/+r standard and really piss off the copyright holders.

JricardoF 2005-08-14 19:55:07 UTC #4

oops

NRen2k5 2005-08-14 21:03:19 UTC #5

Who gives a damn about "1:1 copying"?

So the disc itself is not bit-for-bit perfect. Who gives a damn? All of the content can still be copied bit-perfect.

espresso 2005-08-18 07:23:12 UTC #6

But will the disc be readable on some device which might have protection against copies if it isn't 1:1 copied?!

Bob_the_bored 2005-08-18 08:56:28 UTC #7

What device would have that? Backed up disks look identical to self authored disks to a player, you can't allow one and block the other.

1:1 would allow you to stop worrying about decoding the disk, but for now that's not a problem.