| narrowing down cause of damaged DVDs
• | | | |
 | narrowing down cause of damaged DVDs
by Kathryn Cates on Mar 18, 2012 at 5:59:49 pm |
I'm burning multiple copies of a DVD created using DVDSP. The first several DVDs played fine. Now I'm getting a 'skipping over damaged area' message in exactly the same place on every DVD.
Some observations:
-there are actually two separate, but nearly identical, DVDSP projects I'm burning (versions of the same video using two slightly different m2v files of identical length, but the same audio file). The error occurs in the same place in each project.
-using the same DVD stock, I copied all the relevant files (DVDSP project, ac3, m2v, PAR folder) to a different computer, and have burned from that machine with no issues.
It certainly *looks* like it's the drive causing the problem - but the fact that the error occurs in the same place every time makes me wonder. (Would a drive that was truly on the outs be so consistent?) Is there anything I haven't thought of that I should look at first before assuming the drive needs replacing?
| | | | |
• | | | |  | Re: narrowing down cause of damaged DVDs
by eric pautsch on Mar 18, 2012 at 8:57:02 pm |
First thing to check is your bitrate? How many mins is your entire project and what's its set at?
Second, what media are you using? The cheap stuff. Buy a new batch and try those
Go over those 2 things to see if that help first
| | | | |
• | | | | | Re: narrowing down cause of damaged DVDs
by Kathryn Cates on Mar 18, 2012 at 9:21:59 pm |
Hi Eric,
Thanks for the suggestions. I doubt it's the bitrate setting, as I have burned this project previously with no issues - and in fact it is causing me no trouble when burned from a different computer.
Not a bad thought on DVD stock - it's not necessarily what I would have chosen, but it's burning just fine from another machine using the same media. Perhaps it's a sinister combination of drive + media quality?
| | | | |
• | | | | | Re: narrowing down cause of damaged DVDs
by eric pautsch on Mar 18, 2012 at 9:37:34 pm |
Doesnt really matter if it worked before, bitrate could very well be the issue. Just for the heck of it, what is it? How long in mins is your project?:) Youre using AC3 audio correct?
A faulty drive is almost always last on the list....but it could be. Because its the same spot, I doubt its the drive....either a bad batch or a bitrate spike at that point. But and combo of a dirty laser and a bitrate spike could cause issues in reflectivity on the disc.
Also did, you test on the same player for each?
| | | | |
• | | | | | Re: narrowing down cause of damaged DVDs
by Kathryn Cates on Mar 19, 2012 at 12:29:36 am |
Bitrate is 5.0 Mbps - project is roughly 100 minutes long - and yep, AC3 audio. The fact that the error occurs at the same spot every time when burned on the first drive is exactly what's giving me pause as well.
Playback on the same machine is one thing I haven't controlled for - but I'll give the lens a cleaning and try a different brand of media and see whether I can get the original machine to play nice. Will let you know what I come up with. Thanks so much for your help!
| | | | |
• | | | | | Re: narrowing down cause of damaged DVDs
by eric pautsch on Mar 19, 2012 at 4:25:35 am |
Is it a VBR encode? If so what is your high bitrate setting?
Bitrates.......Buy another batch.....test on several players to isolate a player issue.....then consider it a bad burner . In that order
| | | | |
• | | | | | Re: narrowing down cause of damaged DVDs
by Kathryn Cates on Mar 20, 2012 at 2:16:24 am |
Update for those playing along at home: drive cleaned, still creates damaged DVDs when using cheap media, but burning the same project to better-quality media has no issues. Still has intermittent bad playback of burned DVDs, regardless of media - so I'm not yet ruling out drive-on-the-fritz as one of what looks like probably several culprits.
(And yes, VBR - max bitrate set to 7.5 mbps.)
| | | | |
• | | | |  | Re: narrowing down cause of damaged DVDs
by Michael Sacci on Mar 20, 2012 at 5:15:11 am |
And yes, VBR - max bitrate set to 7.5 mbps.
You can stop there. That is too high. If playback happens at the same spot from disc to disc it is almost always a bit rate issue. Vbr max should never be higher than 7Mbps.
| | | | |
• | | | | | Re: narrowing down cause of damaged DVDs
by eric pautsch on Mar 20, 2012 at 6:04:09 am |
Yeah....you beat me to it. :) Id bring it down a little with a new encode to see if that clears the issue first.
| | | | |
• | | | |  | Re: narrowing down cause of damaged DVDs
by Alexander Kallas on Mar 21, 2012 at 10:58:30 am |
Problem with VBR is that rates above 7mbs can/will produce ugly spikes that will exceed the allowed upper limit. You can see this problem in a bit-rate analyser.
Cheers
Alexander
| | | | |
| |
|
Reply
Like
