Arrgh! audio sync problems

[AndyP]

Am trying to DivX Pitch Black (Region 1) Unrated DVD. I get audio sync problems. The beginning is fine but by the end

the video runs about 1 sec before the audio. I do the following

(1) SmartRipper 2.41 in Movie Mode to rip
(2) DVD2AVI to create .d2v and extract .wav
(3) Use following script for VirtualDub 1.4.9 with Divx 5 free (2 pass - bitrate 1616kbps)
--
LoadPlugin("mpeg2dec.dll")
LoadPlugin("decomb.dll")
mpeg2source("E:\Pitch Black.d2v")
crop(3,54,712,367)
Telecide()
Decimate(5)
BicubicResize(640,272,0,0.5)
--
[decomb functions needed as FILM 90% and some NTSC in middle]
(4) LAME to convert wav to mp3
--
lame -h -b 96 --resample 48 "%1.wav" "%1.mp3"
--
(5) Nandub 1.0rc2 to combine avi with mp3

I have also tried getting ac3 from DVD2AVI and using avid 1.8 with exactly same problem.

I know it works because with Xmpeg 4.2a and Lame ACM 0.90d codec the sync is perfect but the video is bad due to part

interlaced.

Help!!!!

Thanks, Andy

[aleksander]

Try reading this guide:
http://www.doom9.org/virtualdub_procedures.htm
There is a section about manual synching..
Also, when multiplexing with the nandub, use Interleaving - you can play with the setting a little bit - and set the Audio Delay (you will get to know this when you get ac3 from dvd2avi).

hope any of this helps....

aleksander

[AndyP]

Thanks for the reply. No audio delay on AC3 as reported by DVD2AVI and I though the .wav output was supposed to be corrected. Have not played with interleaving, will try now. Have read guide an am trying the sync methods, but I was kind of hoping to find the error in the method rather than just fixing it!!! (I'm sure its something obvious I am missing... just can't see it!)

Thanks again, Andy

[aleksander]

What I would recommend you is to always use Demux (not Decode) in dvd2avi. You will get an ac3 file. Later you can use BeSweet or HeadA3he for transcoding this into anything - wav, mp2, mp3, vorbis....
Or if you prefer you can use Stream Processing in SmartRipper. You will get your video and audio separately.
I always do like this and never had any seriuos sync problems that couldn't be resolved in any way...
And one more thing - I'm not an audio expert, but why do you resample to 48kHz a file that already is 48kHz???

aleksander

[AndyP]

Thanks for reply (again!). I have tried demuxing with dvd2avi and encoding ac3 stream with azid and then lame. Same problem. I have not tried with smartripper... will try.

In Lame if you use a bitrate below 128kbps it will try to resample automatically at 32kHz or something like that. By using --resample 48 you force it to stay at 48kHz, so no resampling occurs! That confused me as well!

Andy

[aleksander]

In Lame if you use a bitrate below 128kbps it will try to resample automatically at 32kHz or something like that. By using --resample 48 you force it to stay at 48kHz, so no resampling occurs!
As I said - I'm not an audio expert and, to be honset, I didn't know about that. I never do my audio below 128 - mostly its 140-160 or if I must use lower bitrate (file size) I use Vorbis....

I only hope that finally you will manage your video to work...

aleksander

[pacohaas]

Originally posted by AndyP
In Lame if you use a bitrate below 128kbps it will try to resample automatically at 32kHz or something like that. By using --resample 48 you force it to stay at 48kHz, so no resampling occurs! That confused me as well!it resamples for a reason...with less bitrate it makes sense to encode at a lower sample rate. for example, a 56kbps mp3 will sound better if it's 22 or 32kHz than if you force it to stay at 48kHz(though neither will sound great).

I suggest you try ABR for better quality, lame --alt-preset 96 is what you want(this works in BeSweet as well)

is it possible that the video doesn't need the decomb stuff? this sounds like a fps problem, so perhaps you should use just a smartdeinterlace filter?

[AndyP]

Wow! I'd forgotten about this one. All fixed ages ago but thanks :)
Now use besweet with a modified --alt-preset 128

Andy

[pacohaas]

haha, i just looked at the date, i was just searching for audio problems in the newbie forum ;)