Log in

View Full Version : fixing corrupt avi, delay video at 57min


MemeX
19th July 2003, 13:49
Hi doom9 and friends,

yesterday i tryed to fix a seemingly quite corrupt avi file. The video plays quite alright except 3-4 frames that look like the colour stays in place where it should move with the outline of persond for example (vid is Div3). Before the fix Windows Media Player and BSplayer would crash if I tryed to seek and usualy i dont have performance problems. I tryed to fix it with Divfix seemed no problem in the indexing, then VdubMod I tryed re-keying it but it didn't want to work somehow and got some software called videofixer which surprisingly did the job but put these few "bad frames" in the vid I described above. Anyway that's what i had to do to fix the vid, seeking is fine just those few frames that I'll have to put up with, no biggy.

The more serious problem was that the audio, which is an .ogg, went out-sync at around 57 minutes. After delaying the video 760ms it was perfect again, I thought a clever idea came to me after a bit of thinking and wanted to cut the video in half at the nearest key frame where it went out-sinc, then just delay the audio streem of the second half by 760ms. All that seemed to have workded fine until i wanted to join the two .ogm segments again, I did all in direct stream copy, but fail to remeber exactly if i did, I know i didn't want to re-encode the audio because of quality loss. What happened is that the ogg audio files were playing like the original file again. After a bit more thinking I gathered that maybe the delay didn't change anything to the ogg audio file and just joined them up right where the other one ended, i thought if i just cut off 760ms of the sencond audio stream I'll get all back in sync (did that with vorbiscutter), didn't want to work either.

Maybe this is due to some error correction thing going on or maybe I'm just not smart enought. I just had an other idea, next time I will try to cut off 760ms of the first stream and append the second stream to that, might work that way around...who knows.

well if any of you have some idea what I'm trying to do and know just the little trick, please give me your guidance :)

Thanks in advance,
MemeX

ps: sorry, i just noticed its quite a bit to read...

ammck55
19th July 2003, 14:52
Welcome to the forum:

Click here (http://forum.doom9.org/showthread.php?s=&threadid=56284&highlight=audio+delayhere/) to view a thread in which this problem is discussed and several solutions offered. This link was the product of a search using the keywords "audio delay", and was not the only solution available. You might also try checking the VirtualDub forum, the FAQ there has much info that will come in handy while working with VDub, or executing searches with more specific keywords. "Asynch audio" is also a term that is frequently used for describing troublesome audio.

Too much information is preferable to too little :) . Good luck

ammck55

MemeX
20th July 2003, 18:32
thanks for the help ammck55, that link is perfect although they haven't found a solution without re-encoding audio. I could have done a search but it didn't come to me that time so i forgot, i only searched manually through Newbies.

Very useful that search option :)
and thanks for the welcome!

MemeX