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JohnnyD
March 31st, 2004, 01:50 AM
After reading a thread about changing bitrates: http://www.drdsystems.com/forum/phpBB2/viewtopic.php?t=73, I wondered about something...

It's about my audio-sync problems... (see thread http://www.drdsystems.com/forum/phpBB2/viewtopic.php?t=51). I noticed that, when I use frame accurate editing, that my bitrate changes from 4800/6000 kbps Peak VBR, at which the recording was done, to 6200 kbps. Basically, the material is still VBR, but it's called CBR now... won't that confuse my DVD-player, making it go out of sync?

I'm still in the process of testing, using different sets of parameters to edit the material, to see what the sync results are, but because the DVD has to be played at normal speed to get the sync problems (fast forwarding does not give the same effect) it's *very* time consuming :?

However, as soon as my tests are conclusive, I'll let you know :)

phd
March 31st, 2004, 06:20 AM
Did you try DMF2? How did it work?

DanR
March 31st, 2004, 06:42 AM
Basically, the material is still VBR, but it's called CBR nowVideoRedo doesn't touch the bit rate fields in the file, so I don't know what DMF1 is looking at to determine VBR vs. CBR.

But, PHD is correct, you really should try a more up-to-date authoring program. DMF1 is years old now. All the major authoring program have free trials. If the sync problems persist with any of the current programs I can look to address it, but I don't think that will happen.

JohnnyD
March 31st, 2004, 07:13 AM
OK, OK, OK... if you all think another (upgraded) authoring program does the trick, I'll try... (grmbl, grmbl)

:wink:

More news next time!

DanR
March 31st, 2004, 07:18 AM
Give it a try, you've got nothing to lose. If you still have sync issues with a current authoring program, I can address it.

JohnnyD
April 8th, 2004, 10:35 AM
Update: I've downloaded a trial-version of DMF3; took some mpg's which played OK on PC and burned them on DVD (+RW). Alas, still audio sync problems, but different: it seems not to progress during playback (but it's hard to tell, really) but it occurs right away at the start of the film... on PC they're OK...

However, I've tried another direction as well: Instead of "Program Stream" I tried recording in "DVD stream". Furthermore, I've put my sound at 224 Kb instead of 384 Kb and I've upgraded my Hauppauge video-drivers... It never hurts to get your source material as good as possible, does it?

The result is, the first trials *seem* to look alright... but I'm still very carefull about it....

More news next time (if you like it or not :) )

DanR
April 8th, 2004, 10:39 AM
HI Johnny D, Keep me posted on the news. I really try hard to insure that sync issues are addressed, so please keep me posted. Remeber, with DMF3 you might need the Movie Factory Compatability option checked (Tools>Options).

Anonymous
April 8th, 2004, 04:16 PM
Hi Dan,

it's looking good... but I'm still feeling like on thin ice :-)

The suspicion I get is, that the problem must be largely due to my source material... Just now I've burned a new DVD (+RW, it would have cost me a load of DVD's if I had done this on DVD+R's :)) with material I've recorded since the driver upgrades etc. which I mentioned before and it seems to be in perfect sync: it starts out perfectly and after 10 minutes it's still perfect...

If this really turns out allright, than it *must* be caused by bad source material; if you're interested, I could send you some for analysis (it doesn't smell or something, so you should be allright ;-)). But let's not be to hasty, it's only the first recording which seems to be okay :-)

I'll keep you informed!

JohnnyD
April 8th, 2004, 04:24 PM
:oops: again. I'm logged in now; previous post was mine as well...

DanR
April 8th, 2004, 04:33 PM
I figured it was you. Who else uses as many :D :) :( :o in one msg? :D

DanR
April 8th, 2004, 04:34 PM
By the way, the ability to change the bitrate header field is done and in testing now. It will be out in the next release.

JohnnyD
April 8th, 2004, 04:41 PM
...you should see me in real live ;-)