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Author Topic: Any ffmpeg (Edit: or Mencoder) experts here? ( Audio/video sync problem)  (Read 2750 times)

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Offline AmigaManceTopic starter

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Hello.
 My Amiga is not powerful enough to play DivX AVI movies without a huge amount of frame-skipping so i use the ffmpeg utility to convert them to MPGs.
 The problem is that both the converted video and audio streams are out of sync with each other. The exact symptoms are:
- The mpg videos are always played with ZERO frame skip, even if some (skipping is absolutely required in order to stay in sync with the audio.
- The audio is not continuous. It plays and stops constantly. Most probable to stay in sync with the non-skipping video.

 I know that i should tweak some of the program's parameters but they are dozens and, for many of them, i don't understand their function. That's why i'm asking for your help. Currently i'm using the -sameq parameter only.
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Offline AmigaManceTopic starter

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Re: Any ffmpeg experts here?
« Reply #1 on: August 09, 2006, 01:51:09 AM »
 Only 27 views? I guess it's not a popular utility.
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Offline AmigaManceTopic starter

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Re: Any ffmpeg experts here?
« Reply #2 on: September 23, 2006, 05:07:21 PM »
 Sorry for the big delay but i was busy with other things.

Quote
In ffmpeg I use "format option" for output (VCD), then all my files are converted in mpeg1video (video) + mp2 64kbs, 22050khz (audio).
When I play files converted to vcd, everything work fine.

PS. I also set the same quality option for VBR enabling.

 So, the command line should be: ffmpeg -i input_file.mpg -sameq -target=vcd output_file.vcd.mpg , right?
 Well, these are the settings that i have been using too and i'm still getting the annoying syptoms that i described in the first post.

Quote
I never try convert to some DIVX format.

 I tried to convert MPGs with the same results... It is frustrating because i can not burn a proper VCD until i find a way to overcome this problem. :-S
 Any other ideas?
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Offline AmigaManceTopic starter

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Re: Any ffmpeg experts here?
« Reply #3 on: September 23, 2006, 06:40:55 PM »
Lazer, i want to use my Amiga and the Amiga version of the FFmpeg tool to convert videos to the VCD format, not a pc.
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Offline AmigaManceTopic starter

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Re: Any ffmpeg experts here?
« Reply #4 on: September 23, 2006, 06:53:37 PM »
 You are right. I didn't mean to be rude. It just that i like to use a pc as less as possible. :-)
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Offline AmigaManceTopic starter

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Re: Any ffmpeg experts here?
« Reply #5 on: April 30, 2007, 10:03:09 AM »
 Damn! It's not a bug of ffmpeg afterall. I have just tried the latest version of mencoder for MorphOS (part of MPlayer archive) and i got EXACTLY the same problem, as i describe it above.. :angry:
 This is so frustrating, what could i possibly be doing wrong!? It seems that only me has this problem. :pissed:
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Offline AmigaManceTopic starter

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Re: Any ffmpeg experts here?
« Reply #6 on: April 30, 2007, 11:49:40 AM »
Quote
Having too slow system to actually play the resulting clip? Sound stuttering would suggest that...

 Certainly not. If i download an original mpg movie from the net and try to view it, the sync is perfect even if i get some frame skipping.
 With MPGs produced by me using Mencoder or FFmpeg, the  sync is horrible and there are no frame skipping whatsoever. Even under high CPU load i get 0 skipped frames!! I'm not sure but perhaps this is what is causing the problem?

Quote
Or does the generated clip have audio sync issues with Linux/Windoze/Mac OS X aswell?

 Most likely, because i tried to produce a VCD compliant mpg and produced a VideoCD out of it. When i tried to play it with my stand-alone DVD player, it had the same problems. So, it's not OS or hardware related.
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