How Important Is File Verification?

[jimmalenko]

Ok if you dont read other peoples posts, but at least try to read your own. I was talking about YOUR backups, not mine. Yes i do backup my dvds, but i dont WATCH a backup, unless you know something i dont know i asume your backups have either reduced quality or split to two disks, in both cases the original is very much preferred. Try to start reading from the top and see who is talking about dvd backups, who brought the subject up (and who owns the originals)

No need to blow a gasket.

You'd rather damage the original and keep the lesser quality backup as insurance ???

[jimmalenko]

...But you gotta admit that it is annoying if somebody posts the same condescending comment over and over in different threads- that being "if you owned the originals". People get it already. And you might want to stop accusing people of bootlegging, even if there is circumstantial evidence to support it...

Read the site rules. I do not want this site pulled down because it has taught me everything I know about video/CDs/DVDs. Copying DVDs yo do not own is clearly illegal - copying DVDs you do own is borderline at best, depending on where you live. That all contributes to the possible demise of this site.

I have never accused anyone of bootlegging, but it seems strange that so many people get pissed when I tell them to make another backup from their original disc. If they owned it, it wouldn't be a problem. The problem comes when they have to pay another $3 to hire it from blockbuster again.

[thor300]

I rather make no copy at all than to not make sure the copy is 100% error free. Anyway, many of my dvds are from DV cam, if my aunt 1200 kilometers up north get a bad dvd from me i cant tell her to make another copy from the original, and verify is the only way to make sure.

[jimmalenko]

I rather make no copy at all than to not make sure the copy is 100% error free. Anyway, many of my dvds are from DV cam, if my aunt 1200 kilometers up north get a bad dvd from me i cant tell her to make another copy from the original, and verify is the only way to make sure.

Fair enough.

I should have looked a little bit further outside the Commercial DVD Backup scope.

[indolikaa]

B's Recorder has 'Verification' and 'Comparison' options. I run them both on every disc. It doesn't take that much longer, and I've had a few instances where they failed and it was legitimate.

I'd rather play it safe.

[ronnylov]

I do almost always verify my burned discs. I also often make a data comparison between the source files and the DVD-R when I put my DVD-R in my DVD-ROM drive instead of my burner. Some discs (of lesser quality) gives verification error in the burner but is OK when read from the DVD-ROM unit and some other lesser quality discs verifies OK but can't be read in the DVD-ROM. I try to avoid this kind of low quality media.

I also do a K-probe scan on each disc to verify the burning quality. I only want good quality discs. I mostly create my own DVD's from tv captures and home videos.

[lordsmurf]

NERO verify is flawed, gives bogus results, waste of time

[indolikaa]

NERO verify is flawed, gives bogus results, waste of time

I wondered if that might be true...

[rixware]

NERO verify is flawed, gives bogus results, waste of time

What does this mean? Is it too strict (more discs fail than should) or too lenient (more discs pass than should)? Is there more documentation available on this?

Is there a faster (and more reliable) method of verifying discs as they are written?

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[lordsmurf]

It has to do with system communication. There's a whole handful of hoops it jumps through. It's not a simple comparison of A to B ... it made it complex, so it fails a lot.

Example: the files burned came from a fragmented drive. Even though the file burned perfectly, and the original is fine, it can fail.

Example: You don't really have a lot of RAM. It can fail. Files fine, just fails.

Example: Your PC has been on too long. Windows acts screwy. Burns fine, files fine. Verify fails.

Get it?

[rixware]

So while it may be unreliable, the result is typically better than it seems. In other words, the burned discs can be fine even if verify fails.

This is consistent with what I've experienced, by the way. A couple of times I had discs fail the Nero verify but come out perfect on a manual verify using DVD Decrypter. I've never had it happen that a disc looked good on the verify but turned out to be bad. In this respect, if it has to be unreliable, at least the outcome is on the good side...

Thanks!

Rick
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[lordsmurf]

I've had it approve LEADDATA and PRINCO discs, but the discs were really BAD after all. Red and yellow blocks in real verification software. Again, don't trust Nero. Maybe I should have added some reverse examples too.

Nero is ONLY for burning. No video, no editing, no verification. Nothing. Just burning.

[pyrohydra]

Interesting thread.

On the subject of Nero verify...I've been thinking that it may not be a good idea to use the burner to verify discs, and use a DVD-ROM instead. Nero's verification is a File Verification tool, and it attempts to verify that the data on the disc is an exact copy of the source on the hard disk. This is different from a surface scan tool such as CDSpeed's ScanDisc, which is a physical test of the disk (It has a data test too, but I don't think this is reliable because it would not have source data to compare it to).

If we're looking for a file verification tool to replace Nero, my idea is to make md5sums of each file before burning. This process takes longer than Nero, but will probably be more reliable. And the md5sums can be tested in a DVD-ROM instead of the burner, which may read the data more reliably.

[rixware]

real verification software

What do you use?

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[lordsmurf]

real verification software

What do you use?

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I don't. I randomly test files myself. I then run a surface test. There are ways to make a more complex verification, but not worth my time, not at all. I have a printout somewhere, but I don't know where anymore. Something I found online, just search for "file comparison" methods in google.