Audio longer than Video. what to do?

[bleeky99]

I have a mpeg1 VCD movie that I downloaded. Both parts play fine prior to encoding, but after encoding the audio gradually loses synch towards the end of each part. I demuxed both parts and found out from WMP that the audio is 4 seconds longer than the video on the first part and 3 seconds longer than the video on the second part. Is this my problem? If so, do I:

1. cut the extra audio off and mux the portions back together?

or

2. Choose 'Do Not Frame Rate Convert' in TMP.(read that on some other posts)

thanks!

[KingJohn]

mpeg1 VCD movie that I downloaded

What are you converting it too ?

[bleeky99]

mpeg2 to burn to dvd

[adam]

If the source was dvd then the different playtimes of audio and video are normal. The audio on most dvds has a delay. The audio is physically longer but it doesnt start playing right away, don't ask me why they do this.

Most dvd->(s)vcd methods just account for this delay so you don't even need to worry about it. I don't know exactly what is causing your sync problems but if they are constant, (ex: whole movie is 2 secs off as opposed to it getting progressively more out of sync as the movie plays) then you can just adjust the delay manually. Use bbmpeg to multiplex and play with the audio delay until the sync is fixed.

[adam]

Ok, just read your latest post. You do realize that 352x240/288 mpeg1 complies with the dvd standard right? You don't even need to re-encode to mpeg2. I think you might need to resample the audio to 48kHz though, not sure.

As far as your sync problems after re-encoding, this may be caused by your software player. Unless you are playing the mpeg2 in a software dvd player you will often get sync problems because not all mpeg2 decoders are made equal.

[bleeky99]

yes, i am encoding to mpg. it starts out fine and as the movie goes it gets out of synch. I almost 99% sure this started when i loaded Elecard mpeg player and codecs. but I had to load this to get TMP to accept .dat files and solve a/v synch problems with svcds. rrrrrg, no winning!

[bleeky99]

i get the synch problems when playing with powerdvd and my standalone player

[offline]

Have you tried simply demuxing the audio and converting
it to 48Hkz, then remuxing back to create a DVD standard MPEG-1
file? There should be no need to reencode to mpeg-2 and
you can loose quality in the process.

[bleeky99]

how do i convert to 48khz. and that link u sent is dealing with avi's, i'm not working with an avi file

[offline]

opps. This link will help

http://www.vcdhelp.com/virtualdubaudio.htm

[KingJohn]

mpeg2 to burn to dvd

HI, If this Mpeg 1 has been downloaded, you need to scan it for junk frames, equally if it was captured it may have drooped frames. Either way if any further processing is done this could throw the audio out of sync.

You can load the mpeg into Vdub for a scan, although if it finds any you will need to save as AVI. However if you load it into TMPGEnc and select File > Mpeg tools > Merge&Cut > MPEG 1 Video CD > Add > Output new file name >Run

This will stream through the Mpeg and can fix simple problems, before you move on to do anything else.

[bleeky99]

i'll try that King John. but through my own testing I found out that if I demux the file, then load the separate video and wave into TMP for encoding it works also. just a FYI. but it looks like my method and yours will take the same amount of time.

[KingJohn]

Well the methods very from peoples own preferences, and they will all depend on if the source has problems, and what those problems are.

Sometimes the lower powered machines will also give problems in many conversions, but the same file works just fine on others machines.

Downloading AVI, is better simply because its easier to work with those files, SVCD downloads are fine, but if they pick up problems on the way it can be a problem sorting them out.

There are times that I also separate the audio, but not until I have gone though the usual route (The quickest way the better)