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View Full Version : Authoring: m2v versus mpg


digidragon
28th March 2005, 16:52
Is there a difference in the way authoring software handles elementary and program streams?

I've been authoring some video converted from PAL to NTSC using DGPulldown. Some I've remuxed into an mpg before authoring, but with others I've fed the m2v and mpa streams into the authoring program.

However, I've noticed several freezes and skips when playing back the DVD. It's not the media (verbatim and ritek) and it only seems to occur on the title authored using the elmentary streams - the titles authored from mpegs seem fine.

When compiling a DVD, I normally use the PC to surf etc. so I compiled one again from the elementary streams and left the PC well alone until it had finished. This time the DVD played without freezes or pauses.

So, when authoring, are mpegs somehow more "robust" than using elementary streams? I normally use mpegs to author, and normally use the PC while compiling, and have not had a freezing or pausing problem.

Any thoughts? Or am I barking up the wrong tree? Or could it something to do with the fact that the m2v was processed using DGPulldown.

Thanks for any ideas.

Paulcat
28th March 2005, 17:15
Personally, I have not had any problems with using M2V's altered with DGPulldown, and I have authored in both ways as you have.

When I am burning, I generally do not open any other programs, and generally close most everything else beforehand...which seems to be what contributed to your poor playback.

Paul

mpucoder
28th March 2005, 17:17
This all depends on the authoring program. Elementary streams must be multiplexed, and many freeware authoring programs do not do a good job of this. Program streams should be demuxed and remuxed on the fly, but several programs use the streams as is adding NAV packs as required. The results of this depend on the original multiplexer, and if it was DVD compliant.
Multitasking should not affect the authoring process, the results should be identical regardless of the mix of programs running on the PC. If not, I'd suggest using a different program.
Burning, though, as Paulcat mentioned, is sensitive to PC load as it is a real time operation. A missed or delayed interrupt from the drive can wreak havoc.

digidragon
28th March 2005, 18:04
I forgot to mention that I use either TMPGEnc DVD Author or DVD-Lab. All streams were DVD-compliant, no re-encoding was done. Problems occured using both authoring packages when using elemetary streams. When I've authored and burned mpg files, I've nearly always used the PC at the same time, without any problems.

Also, my burner has BURN proof to avoid buffer underruns, so I don't think the burning stage was the cause.

Thanks for the replies.