Audio stays behind!

[emilsoft]

Hello everyone, I just downloaded this Xvid movie, it plays perfectly fine in Xvid format except that it has a scene that gets pixelated for about 3 seconds (pink and green pixels) then it continues playing fine. Now I'm trying to convert this video into a VCD so that I can watch it on my DVD player.

I've used TMPGEnc, Ligos, MainActor and the encoding goes fine, except when I try to view the mpeg file the audio starts satying behind exactly after the pixelated scene!

Is there any way to fix this without having to redownload the whole thing over again, cause I'm on dial-up!

Thanks alot. Any help would be greatly appreciated!

[DrinkOrDie]

Nearly all those "downloaded" video's, expecially Xvid, have errors in the video stream. Most of the time, your PC can play through the errors with no problems.

It is SOMETIMES possible to patch such an error and maintain audio sync for conversion to video CD, but most of the time, it's a real pain. Bottom line is, if there's errors (that pixilation you described) you cannot re-encode or convert without serious audio sync problems.

My suggestion is to forget about it. Even if you are successful, it will only be after much aggrevation.

If you got the video where I think you got it, just take it for what it is and be happy with it. You want perfection, go buy the DVD or VCD.

[emilsoft]

Originally posted by DrinkOrDie
Nearly all those "downloaded" video's, expecially Xvid, have errors in the video stream. Most of the time, your PC can play through the errors with no problems.

It is SOMETIMES possible to patch such an error and maintain audio sync for conversion to video CD, but most of the time, it's a real pain. Bottom line is, if there's errors (that pixilation you described) you cannot re-encode or convert without serious audio sync problems.

My suggestion is to forget about it. Even if you are successful, it will only be after much aggrevation.

If you got the video where I think you got it, just take it for what it is and be happy with it. You want perfection, go buy the DVD or VCD.

ooook, thank you for your reply. I'm pretty sure you know where I got it from But let's say I'm willing to go through the pain and the headache for fixing the error, any way I can do it?

Thanks again.

[DrinkOrDie]

*sigh*.........

" This Xvid movie" doesn't tell me much. I need a frame of reference in order to give ANY real prognosis beyond my initial response.

How about using virtualdub to open that downloaded file, then choose 'file - file information'.

When the box pops up, showing file information, send me a screenshot. (hit the "prnt scrn/sysRq" key, then open MS paint. Click "edit.. paste". then "file save as" Save as a JPEG file.

Then reply to this post, and attach the JPEG screenshot of the file info. The way to attach a picture to your post is shown at the very bottom of your reply, or post new thread page.


ONly with that info can I proceed any further. Good luck TKS..

[emilsoft]

Oh, sorry. Here you go:



Oh, and also the frames that I've discovered to be corrupt are:

68761 to 68969

and

94458 to 94516


Thanks.

[simbalin]

try to fix with avifixed, encode only the source range about 1 minute around the corruoed frames. What happens?

Didn't work?

Try use VirtualDubMod as frameserver, served me well to solve those problems

Didn't work?

well, since this is a simple error only at 1 point in the movie I would say it is not too much to adjust the audio Stream

Version1:

• Slit it exacly at the broken part,
• demultiplex the non-synchron part (the second as it appears
• use bbMPEG to multiplex it using Video and Audio Delay time to fix the problem
• done]

Version2:

• demultiplexy the wohle thing
• open both streams in a program like premiere or as i do Cool Edit Pro v2.1
• cut the Audio at the broken frame, slide the second half so the movie is synchron once again. Use the Video Window to check your work, works just perfekt (though u should have worked with Cool Edit 2000 or Pro before, most of the prog explains itself - the helpfile is worth double the price)
• Safe a merge Down of your fixed Audio parts
• multiplex it once more
• done

Might take a while if u do this the first time.

@DrinkOrDie: what good was the movie info for this?



Greetz Simbalin

[DrinkOrDie]

Well I must apologize for being away and for my delay in responding. The screenshot is a start. Knowing what frames are bad is a good second step.

Forget about "multiplexy" or whatever was said by 'simbalin'. That only applies if we are trying to fix an MPEG. Not the case here.

I will assume that the "glitch" (pink and green pixelation) plays through on the PC and that the audio remains in sync. The problem is trying to convert the file with video errors, and you are using the file as a source for both A/V causing a sync problem.

That's a start. If all that is true:

Lets seperate the audio from the video

Open the file in VirtualDub.
Set audio to FULL PROCESSING MODE
Set Audio compression to NO COMPRESSION (PCI)
Set audio conversion to 441.. HIGH QUALITY. that gets the audio ready. converts it from 48 to 44.

Set video to DIRECT STREAM COPY. (saves a step later)

In VirualDub, choose FILE - save wav. vdub will then save the audio stream to the location/name you choose. Perhaps save it as "'movie name' SOUND" to your desktop.

The resulting audio will be a very large file but will also be the best audio source for your conversion. Don't attempt to open that wav to see how it sounds. It's likely the PC will hang unless you have 2 gigabytes or so of ram.

Now you should have the audio part of the movie, (the wav you just saved) bitrate no longer a factor, and sample rate no longer a factor now that it's a seperate audio track and I assume it will be the same time length as the original AVI. In short, your audio wav file is no longer dependent on the fked up video part of the file.

Now, the video stream: you need to 'mask frames' covering the bad frames. This can be tricky, especially with more than one area of the movie needing fixed. Make sure that your video is set to DIRECT STREAM copy.

When you mask frames, what will happen is that vdub will basically repeat the last good frame and carry that last good frame over to cover up the bad frames, thus not affecting the time length of the movie. Next good frame will continue on it's way. Watch where you are masking. If you mask an "I" frame, you will also mask all frames in between until the next "I" frame. In short, don't mask an "I" frame unless there are bad frames between it and the next I" frame. If an "I" frame is at the end of the bad part, back up one frame and end the mask there.

After you mask the bad frames (like I said, it can be tricky) then
select under AUDIO - NO AUDIO.

Then choose FILE - save as AVI. perhaps save to desktop as 'movie name SILENT vid' You will see Vdub saving VIDEO data but no audio data.

IF you are succesfull you should now have a video stream with NO audio, and the errors (bad frames) should be covered up with a good frame(s). basically, the bad frames will appear as if the last good frame continued to go on in time, covering up the bad frames with good ones, but all the while keeping the same time length as the original.


Assuming the video fix and audio seperation went well, you should have 2 files. One will be a video stream with the bad frames masked, but no audio.

You are done with vdub if you have 2 files of equal time length: One that is video only, bad frames masked, and 1 that is audio only.

Use those files as your input for tmpegnc conversion to mpeg. Choose the audio and video you created with vdub as seperate input under the audio source/ video source buttons.

There are many things that can go wrong, but that's basically how to do it. if you can manage to get audio and video seperated from the original file, same time length, but cover up the errors in the video, tmpegnc will make a nice mpeg for ya. Don't forget to choose the correct template.

For a 25fps source, I recommend using the VIDEO CD template the is 23..something FPS. it's closer to your source than 29.97fps.

After all this, I still think it's going to be a headache, but I did manage to make it work (eventually). and the method I used stood the test of time through several bad frame movies.

Good luck.