New submission from LostCause <[EMAIL PROTECTED]>:

Not sure if you've already found a solution, but I was experiencing a 
similar problem while trying to prepare an AVI for burning to a video 
DVD with the following command entry:

$ ffmpeg -i invideo.avi -target dvd -r 29.97 -padtop 94 -padbottom 94 -s 
720x292 -fs 4200000000 -y outvideo.mpg

Using ffmpeg in like fashion has never failed me, but in this 
instance... the audio of the resulting mpeg was about 7.5 seconds ahead 
of the video. Instructions at http://howto-pages.org/ffmpeg/ led me to 
believe the following variation would be my solution (Note: Nothing from 
the -target option to the end of the line is actually relevant to the 
issue in question).

$ ffmpeg -i invideo.avi -itsoffset 00:00:07.50 -i invideo.avi -map 0:0 
-map 1:1 -target dvd -r 29.97 -padtop 94 -padbottom 94 -s 720x292 -fs 
4200000000 -y outvideo.mpg

Played around with the parameters for a couple of hours to no avail... 
NOTHING seemed to have ANY effect at all on the output.  So I started 
shotgunning options and found what worked after a few tries. The 
following did the trick and makes more sense than specifying the same 
input file multiple times and using the -map parameter (at least to my 
feeble mind).

$ ffmpeg -itsoffset -00:00:07.50 -i invideo.avi -target dvd -r 29.97 
-padtop 94 -padbottom 94 -s 720x292 -fs 4200000000 -y outvideo.mpg

It's the exact same entry as was started with except for the -itsoffset 
option placed before the input with a negative value.... DUHHH! The 
beginning of the resulting mpeg was cropped off (the part where the WB 
logo fades in... no big deal for my needs). I'm assuming that using an 
-itsoffset value of negative 7.5 seconds is telling the video stream to 
begin 7.5 seconds "before" the movie actually starts... so-to-speak. I 
understand (I think) what the entry says to do... but don't understand 
why I can't apply the -itsoption to the audio stream with a positive 
value... in other words, tell the audio stream to start late rather than 
tell the video stream to start early. In any case , it all works out the 
same and is satisfactory unless one doesn't want to chop off the 
beginning of the video stream. Google usually saves me much grief in 
such situations... but this time it just wasted a couple of hours.

Hope this helps someone. Otherwise... apologies for reiterating the 
obvious, if that's what's been done... I'm new to the mailing list.

KLH

----------
messages: 2837
nosy: LostCause
priority: normal
status: new
substatus: new
title: itsoffset has no effect

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