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View Full Version : Dynamic synce issue


Mancora
17th April 2002, 03:18
ok now ive had problems in the past with encoding in ABR, where the audio starts off in sync however if i skip ahead to another part of the film the audio really desyncs, sometimes with a large silence before i hear sound which is out really of sync othertimes teh sound starts right off but its really out of sync

the abr i was using then was 112


now im my search i found this


"If you let GKnot do your audio encoding, you shouldn't see sync problems. However if you encode audio below 128kbps, there are special considerations that will affect both sync and quality if ignored. From the Help tab in Gknot:

quote:
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audio-bitrates below 128 (in lame) can cause sync-problems (and sound terrible), because lame is automatically
downsampling to 32 or even 22kHz. i highly recommend to use
128 or 160 and nothing else. to avoid downsampling you have to add "--resample 48" to your lame commandline options if
you encode at low bitrates.
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You might want to also read Doom9's Guides for the tools you are using, if you have not done so already."




is there anyway to get past this so there isnt a sync issue in playback without re-ecoding the whole thing?

and would that be the same problem im having (since it starts off in-sync yet get farth off sync the father i skip ahead in the movie (dynamic sync issue))?

MaTTeR
17th April 2002, 04:32
Would it be a correct guess if I thought you used Flask or Xmpeg to encode video? If so, I think you'll find that's a common problem with those applications and pretty well documented in the past. I'd highly suggest using Gknot for your encodes, you won't see sync issues.

Downsampling to 44kHz with LAME won't cause your sync issues. It has been reported that downsampling anything lower that 44kHz will cause sync problems though.

You should really try Vorbis out instead of LAME:)

Mancora
17th April 2002, 04:51
to encode my video i used nandub,

hehe, i havent been able to get gknot to work for me though nandub works like a wet dream

Mancora
17th April 2002, 05:18
i havent used vorbis, though im wondering of a fix because i already have some video clips that are encoded in an unknown way though i think it was ABR because it is reactign the same way as when i encoded with ABR, now i can encode them into VBR to fix the sync issue and that works though its a pain to have to do