Video changes speed but audio stays the same.

[rosbif08]

Hi everyone,
I wasn't sure if this was appropriate for the audio sync thread as I think this is a bit more complex...
I have an AVI film which behaves very strangely. Basically:

- When I open it in Windows Media Player it plays fine (audio + video correct speed)
- If I pause the video and press play again, the video appears to play at twice the speed but the audio remains the same.
- If I open it again so it plays properly and then click somewhere else along the seek bar or resize the screen, the video plays at twice the speed again as well as stuttering/sticking. The audio is still fine.

Does anyone have an explanation or possible solution for this ? Any help would be appreciated !

Thanks

[minidv2dvd]

the easiest explanation is that not all avi are created equal. some are made properly with the correct tools and some are not. you could try a some of the avi repair apps in the tools section to try and fix it or use them to re-encode the avi into a working state.

[manono]

Does anyone have an explanation or possible solution...

Don't download garbage from the Internet? Post a GSpot pic of the AVI and it might provide some clues. You've provided next to no useful information about the video.

[rosbif08]

Thanks for the suggestions. Usually I don't download crap from the internet but unfortunately this isn't very widely available elsewhere !

Is this of any use ?

[manono]

That blows my theory. I thought it might be related to audio with a low sampling rate. About all I can suggest is to Direct Stream the audio and video and see if that straightens it out. Otherwise I doon't know. Perhaps someone else has an idea.

[jagabo]

I think I've seen such things happen with a screwed up AC3 decoder. Try using a different one.

Try using VirtualDub to demux the audio and video. See if the video alone plays properly. If so, try muxing the audio and video back together with VirtualDub.

[rosbif08]

I think I've seen such things happen with a screwed up AC3 decoder. Try using a different one.

Okay I better add this : before I got this particular film I had another AVI that had no sound at all just video. After reading up online I saw that I might need some AC3 codec. So I downloaded one of those and the sound started working (although on that one the sound and video were out of sync but that's another issue). On my list of programs this thing I downloaded appears as an "AC3 filter", what is the difference between that and an AC3 decoder ? Which one do I need ? Would you suggest I get rid of the one I have Sorry you'll have to bear in mind I don't know what any of this means

Try using VirtualDub to demux the audio and video.

I was going to give that a try but it wouldn't open it and kept giving me a msg saying I need a VFW compatible codec. I tried getting some from various places but it still didn't work... where can I get one that works ?

Thanks for the help !

[poisondeathray]

AC3 ACM is required for AC3 in vdub

right click the .inf to install

[rosbif08]

Okay I just installed that......... still doesn't work ?? :S

[poisondeathray]

Are you sure you installed it correctly?

Can you see AC3-ACM codec in vdub when you select audio=>full processing, audio=>compression?

[rosbif08]

Yeah !! Here's the proof :S

[poisondeathray]

post the entire error message regarding the "vfw codec" or any other error message

[rosbif08]

Here's all I get...

[poisondeathray]

Yeah, that refers to the video, not audio. XviD.

You have to install XviD codec, I'm pretty sure that it contains the VFW (video for windows version), if not ffdshow in the vfw interface does for certain.

EDIT: this version says it has the vfw version
http://www.xvid.org/Downloads.15.0.html

Another approach on Manono's suggestion to direct stream copy the contents into another container: Try avidemux (which has self-contained codecs, no need for external stuff). Leave video and audio set to "copy" in the sidebar, set format to "avi". Press save with extension (e.g. "myfile.avi")

Also, try playing in VLC or Mplayer (which also have built in codecs). It might be a WMP problem

[rosbif08]

Well I don't bloody believe it. First thing I did was get VLC, and it plays fine on it!!!! Thanks a lot ! But now I have questions... does it not play properly in WMP because there's something wrong with the file or because WMP is rubbish ? And before I attempt to burn it onto DVD, is it likely to burn properly or will I probably have more problems ?

Thanks for everyone's help anyway

[poisondeathray]

Well I don't bloody believe it. First thing I did was get VLC, and it plays fine on it!!!! Thanks a lot ! But now I have questions... does it not play properly in WMP because there's something wrong with the file or because WMP is rubbish ? And before I attempt to burn it onto DVD, is it likely to burn properly or will I probably have more problems ?

Well WMP is rubbish , but part of the explanation might be that you have an outdated XviD install

If you just burn to DVD for a DivX compatible player (as in burn .avi data files), you should be fine
EDIT: scratch that, if your Gspot pic is correct, that 1024 dimension is too big. 720 is the usual max for most standalones.

If you want to make a standard DVD, you have to re-encode and author a DVD

[guns1inger]

Both. VLC is designed to play partial and broken video, so it can handle a lot of crap that other, less robust players cannot.

So you can now watch the video on your PC. You have not, however, fixed the underlying problem, so any attempt to convert the video to another format, or play it on a standalone player, will likely meet with failure.

[rosbif08]

If you want to make a standard DVD, you have to re-encode and author a DVD

Where can I find out what that means and how to do it ?

EDIT: And if someone wouldn't mind explaining, how do I go about the earlier suggestions of making a direct stream copy and using vdub to see if the video plays properly on its own, because I dl'd the xvid thing and now I can open the videos...

[poisondeathray]

An easy way to make AVI=>DVD is FAVC or DVD Flick (both free). Under each tool you will find a list of guides /walk throughs to help you

(You probably don't need to do this anymore) In vdub, select video=>direct stream copy, audio=>direct stream copy, file=>save as avi

[jagabo]

If you want to make a standard DVD, you have to re-encode and author a DVD

Where can I find out what that means and how to do it ?

https://www.videohelp.com/guides?searchtext=&tools=&madeby=&formatconversionselect=AVI+...or+List+Guides

[rosbif08]

Just in the interest of people who might benefit from this thread, I burned the file onto DVD using DVD Flick and it worked perfectly !! It may have taken over 3 hours but it was worth it ! FAVC did not work.

Thanks to everyone for their help