copied dvds. bits and bytes....

luv2liv

Diamond Member
Dec 27, 2001
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somebody please help me out here!

my friend told me copied dvds are no good. thats why he would never dare back up his dvd collection. and then the example goes back to VHS. he exclaimed: "see! the 100th copied version is never the same as the original!!!"

all this time i thought dvds are pure 1 and 0. with some CRC built in to verify and ensure the copied are the same no matter what. assuming theres no dirt and scratches.. there shouldnt be any errors from each copy session. when there is an error detected, my Nero stops immediately.

so what happens when i sit there and copy 1 disc from a previous successfully burned disc and repeat till i hit 100th copied disc? would you see a difference???
 

Fardringle

Diamond Member
Oct 23, 2000
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As long as each copy was completed without errors on media that is intact (so no scratches or missing data), then the 100th copy will be identical to the first.
 

luv2liv

Diamond Member
Dec 27, 2001
3,500
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As long as each copy was completed without errors on media that is intact (so no scratches or missing data), then the 100th copy will be identical to the first.

thats what i thought too! now im trying to find some scientific article or from some good sources of info as evidence for the friend...
 

sswingle

Diamond Member
Mar 2, 2000
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Explain to him its digital vs analog. VHS was analog. The source had to be played back and sent through possibly inferior hardware and cables to another deck before it was copied. In the digital world, the computer can verify that the 0s and 1s are in the exact same order before making the new copy.

Lets say you post up a picture on a forum. The image quality isn't degraded because 100's of people downloaded (copied) the picture to their own computers to look at it.
 

corkyg

Elite Member | Peripherals
Super Moderator
Mar 4, 2000
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This is exactly why the industry went to copy protection methods such as DRM - because digital copies are 100% identical to the original.