[Extractstream [MM]] FW: [ExtractStream] audio syncing problems

[Roger Ly]

This is a multi-part message in MIME format.

---------------------- multipart/alternative attachment
Adding to this list as well...=20
=20
-----Original Message-----
From: Roger Ly=20
Sent: Thursday, November 14, 2002 10:27 AM
To: ExtractStream@yahoogroups.com
Subject: RE: [ExtractStream] audio syncing problems
=20
Hey Don,
=20
Tried it last night, and it doesn't seem to be working correctly.
=20
I tried three things:
=20
1.	Using my compressed audio file that I had manually set to be the
same length as the video stream.  I also used the frame rate setting you
suggested, and it seemed to have the same syncing problems as before.
Frame rate adjusted from 29.97 to 29.71
2.	Just extracting the audio, doing WinAmp->Wav conversion and then
CoolEdit -> 48KHz conversion.  (not compressing the audio length to the
exact length of the video stream)  Using that audio stream in VirtualDub
using the frame rate setting you suggested.  It's still off, probably
about the same as it was before.  At the beginning its fine.  After 8
minutes, it is about half a second or so off (audio comes before the
video).  Frame rate adjusted from 29.97 to 29.73
3.	Using besweet, lame and ssrc to convert and 48Khz at the same
time.  The interesting thing is that it made my audio file a good 100
minutes LONGER than my video.  Using WinAmp and CoolEdit only seemed to
make it 20 or 30 seconds longer.  Also, when I tried to set the frame
rate setting as you suggested, the audio offset was completely off.  I'm
not exactly sure why.  (When I say off, I mean a good 40 or 50 seconds
off early on... I assume it got much worse as you watched more and
more).  Frame rate adjusted from 29.97 to 23.21!!!!
=20
So they all seem to be off (the first two are pretty similar to my
original tests, and the third one was just completely wrong).
=20
Let me verify that I changed the correct setting.  The frame rate match
option should decrease my video frame rate a little if I choose that
option, correct?  (Assuming, as in my case, the audio is longer than the
video).  I was kind of hoping it could drop a couple of audio frames and
keep the video at 29.97, but oh well...
=20
Are there any other suggestions? =20
=20
Thanks,
=20
Roger
=20
-----Original Message-----
From: Don McAllister [mailto:donmc@blueyonder.co.uk]=20
Sent: Wednesday, November 13, 2002 2:58 PM
To: ExtractStream@yahoogroups.com
Subject: RE: [ExtractStream] audio syncing problems
=20
Yes, skip it completely. I used to have horrendous sync problems until
this option was pointed out to me. Basically you don't have to worry
about the lengths, VirtualDub does it automatically for you.
=20
It's one of those smack on the forehead type moments when it finally
works.
=20
I hope it works OK for you. Let us know how you get on.
=20
As an aside, I use besweet and lame to convert the audio m2a track. They
are command line driven so the following command file does the
conversion to wav and 48Khz in one go. I think I downloaded lame
separately but just copied it into the besweet directory.:
=20
rem Echo off
set TivoUtils=3Dd:\Tivoutils
set TivoData=3Dd:\TivoData
=20
for %%F in (%Tivodata%\*.m2a) do %TivoUtils%\besweet\lame --mp2input -s
32000 --decode "%%F" "%Tivodata%\%%~nF.tmp"
=20
for %%F in (%Tivodata%\*.tmp) do %TivoUtils%\besweet\ssrc --rate 48000
--bits 16 --twopass --normalize --dither 1 "%%F" "%Tivodata%\%%~nF.wav"
=20
del /F /Q %Tivodata%\ty\*.tmp
=20
This will work on windows 2000\XP, probably not on Windows98.
=20
=20
=20
Don
-----Original Message-----
From: Roger Ly [mailto:rly@homestead-inc.com]=20
Sent: 13 November 2002 22:28
To: ExtractStream@yahoogroups.com
Subject: RE: [ExtractStream] audio syncing problems
Hey Don,
=20
Should I skip the step I did at the end where I compressed the audio
stream to be the same length as the video stream?  On a four hour audio
stream, it took me three hours to compress, and I'd like to avoid that.
=20
Will checking the "Change so video and audio durations match" option
work with the two streams at different lengths?
=20
Can't wait to get home and try this out tonight!
=20
Thanks Don!
=20
Roger
=20
-----Original Message-----
From: Don McAllister [mailto:donmc@blueyonder.co.uk]=20
Sent: Wednesday, November 13, 2002 2:25 PM
To: ExtractStream@yahoogroups.com
Subject: RE: [ExtractStream] audio syncing problems
=20
Roger, You're nearly there!!
=20
Once you've loaded the audio and video file in VirtualDub select
=20
Video=3D>FrameRate
=20
Click the radio button "Change so video and audio durations match"
=20
You'll now find your audio in perfect sync.
=20
Cheers
Don
=20
-----Original Message-----
From: Roger Ly [mailto:rly@homestead-inc.com]=20
Sent: 13 November 2002 21:58
To: ExtractStream@yahoogroups.com
Subject: [ExtractStream] audio syncing problems
Hey all,
=20
I'm sure this question has been beaten to death on this forum, but I
can't seem to get a good answer:
=20
I've been cutting and editing video extracted from my Tivo, and can't
get the audio to stay in sync.  The following is an outline of what I've
been doing.  The end goal is to burn to DVD.
=20
Run TivoApp and extract the ty stream to my Win2K box.
Use TyConvert to convert to a multiplexed mpg file.
Use DVD2AVI to demultiplex.
Used WinAmp to convert the m2a file to a wav file.
Used CoolEdit2K to convert the wav file to 48KHz
Loaded the .d2v file into VFAPIConv for an avi to be used in VirtualDub
Loaded the avi and the wav file into VirtualDub.
=20
Now, when I play the file in VirtualDub, the video/audio starts in sync.
Over time though, the audio and video become out of sync, and the audio
starts coming before the video.
=20
A couple of things that I noticed.  After demuxing with DVD2AVI, the
audio stream is actually longer than the video stream.   The video
stream is 4 hours and 30 minutes and 29 seconds.  The audio stream is
4:30:49 (or something similar). =20
=20
I thought this would account for the sync problems, so I used CoolEdit
to compress the audio stream to 4:30:29, but I still get the sync
problems.
=20
Am I missing something obvious here?  What's causing the video and audio
to start off in sync, but slowly become out of sync over time?
=20
Does anyone have any better suggestions on how to do this?
=20
I've checked Roger M's Tivo page.  I also based my last efforts on
http://salfter.dyndns.org/tivo2svcd.shtml. =20
=20
TIA,
=20
Roger
=20

To unsubscribe from this group, send an email to:
ExtractStream-unsubscribe@yahoogroups.com



Your use of Yahoo! Groups is subject to the Yahoo!
<http://docs.yahoo.com/info/terms/>  Terms of Service.=20

To unsubscribe from this group, send an email to:
ExtractStream-unsubscribe@yahoogroups.com



Your use of Yahoo! Groups is subject to the Yahoo!
<http://docs.yahoo.com/info/terms/>  Terms of Service.=20
=20

To unsubscribe from this group, send an email to:
ExtractStream-unsubscribe@yahoogroups.com



Your use of Yahoo! Groups is subject to the Yahoo!
<http://docs.yahoo.com/info/terms/>  Terms of Service.=20

To unsubscribe from this group, send an email to:
ExtractStream-unsubscribe@yahoogroups.com



Your use of Yahoo! Groups is subject to the Yahoo!
<http://docs.yahoo.com/info/terms/>  Terms of Service.=20

To unsubscribe from this group, send an email to:
ExtractStream-unsubscribe@yahoogroups.com



Your use of Yahoo! Groups is subject to the Yahoo!
<http://docs.yahoo.com/info/terms/>  Terms of Service.=20

---------------------- multipart/alternative attachment
An HTML attachment was scrubbed...
URL: http://lists.merlins.org/archives/extractstream/attachments/20021114/c0f62d4c/attachment.html

---------------------- multipart/alternative attachment--