How do I get audio/video to sync

[spottyrover]

any help on how to get the audio/video to sync would be appreciated
In the past I just recorded soccer (football) so syncing was not a big problem.
The information I have found all relates to dvd ripping which I assume is not relevent here.

Now I would like to record and make the ocasional DVD using devede
and editing with kdenlive.
Any sugestions would be appreciated

mencoder -oac mp3lame=1 -fps 25 -ovc x264=1 -x264encopts crf=22:threads=auto -tv driver=v4l2:norm=pal-i:input=1:adevice=/dev/dsp:audiorate=48000:width=384:height=288 -af volume=-7 -endpos 02:15:00 -o /media/sdb1_TV/1_TV/Soccer/soccer-game3.avi tv://

Thanks for your help
Dave

[blaz]

Not sure if this is what you want to do, but in the past I've fixed some out-of-sync avi files with this:

mencoder -ovc copy -oac copy -audio-delay -0.5 "outofsync.avi" -o "insync.avi"

This delays the video by half a second. +0.5 delays the audio by half a second. You have to play with it to get the right delay value.

[robinsonlove]

try another avi to dvd decoder to do that again, it depends on your file size or dvd burner quality,

[spottyrover]

Sorry for not being clear
It is in the initial recording (from the composite input)
The audio/video sync is spot on in the beginning but progressively goes out of sync as the recording goes on. By the time 2 hrs are up the video has stopped talking when the sound starts

Blaz your fix does it just shift the sound/video relation or stretch it?

Thanks for your help guys

Dave

[blaz]

Sorry for not being clear
It is in the initial recording (from the composite input)
The audio/video sync is spot on in the beginning but progressively goes out of sync as the recording goes on. By the time 2 hrs are up the video has stopped talking when the sound starts

Blaz your fix does it just shift the sound/video relation or stretch it?


Pretty sure -audio-delay just shifts, not stretch.
Sorry, never had this problem.

[talen9]

Try searching for "sync" into this same forum (Linux, Mac OS X & co.), you'll find more than one asking for solutions to notorious mencoder a/v sync ... like this one (http://forum.doom9.org/showthread.php?t=134896&highlight=sync) or this one (http://forum.doom9.org/showthread.php?t=132655&highlight=sync).

This other one (http://forum.doom9.org/showthread.php?t=122082&highlight=sync) specifically addresses A/V sync problems with mencoder/x264, see if it fits.


Please remember that (generally speaking) an x264 stream in an AVI container is usually not the optimal choice; since MEncoder's internal MP4 muxing is slightly borked (IIRC), maybe you're better stay with AVI, though (please wait for more answers about this matter!).


PS: now that I look better at your command line ... are you definitely sure that your audio sampling frequency is 48000 and not 44100, in a PAL TV recording? Please note that I *never* did any A/V capture, so possibly I'm only saying something very stupid :P

[cord-factor]

spottyrover, try to record with similar command (DV-Video):
mencoder tv:// -o "capture.dv" -tv input=3:width=720:height=576:audiorate=48000:amode=1:alsa -oac pcm -ovc lavc -lavcopts vcodec=dvvideo -of lavf
After that compress it with your favorites.

It is possible to record with else video codec and file format, but the sound must be PCM.

[blaz]

Please remember that (generally speaking) an x264 stream in an AVI container is usually not the optimal choice; since MEncoder's internal MP4 muxing is slightly borked (IIRC), maybe you're better stay with AVI, though

Yes, a script like h264enc creates a default avi with mencoder, but then extracts the h264 and audio parts with "MP4Box -aviraw".

It then puts the audio and video back together into containers like mp4, m2ts, mkv using better, container-specific tools, not mencoder.

The avi file with h264 that mencoder creates does play fine with mplayer though!

[spottyrover]

I tried changin the audio to 44100 but the recorded sound had a noise on top of it.
I will look at the rest of the suggestions tomorrow

Thanks for all of your replys

Dave

[mousemurder]

theres also avisync

i think part of transcode family...

edit: i think this shifts and not streches also...

have you tried changing the fps ?