How to prevent Sync Loss when converting video..

[BiZzZzaaR]

Im just courious how to avoid the audio not matching the video. Any programs that might help or options i should play with when converting? PLease DONT Lock me! Just need some info!

[redwudz]

What format is the video and what format are you converting to?

If you are converting AVIs to MPEG, watch out for MP3 VBR audio. It can cause sync problems when encoding. The next common causes of sync loss are missing video frames or corrupted audio tracks or bad joins in the file.

For MP3 VBR audio, I usually save it out as a WAV in VirtualDub Mod, then convert it to AC3 audio with ffmpeggui if my final destination is a DVD. I add it back in during authoring. You can use VDM to check an AVI for errors, also.

[zoobie]

don't use compressed audio

[mats.hogberg]

If you're looking for AVI to DVD conversion (which is a process prone to sync problems if the AVI sports VBR audio), try convertx2dvd or its predecessor divx2dvd.

/Mats

[BiZzZzaaR]

What format is the video and what format are you converting to?

If you are converting AVIs to MPEG, watch out for MP3 VBR audio. It can cause sync problems when encoding. The next common causes of sync loss are missing video frames or corrupted audio tracks or bad joins in the file.

For MP3 VBR audio, I usually save it out as a WAV in VirtualDub Mod, then convert it to AC3 audio with ffmpeggui if my final destination is a DVD. I add it back in during authoring. You can use VDM to check an AVI for errors, also.

im not sure what format they are converting to, but they are AVIs at the start. then i have been using Nero 7 to convert to DVD and it does all the converting 4 me. I did notice in the video options in Nero, i can change the converting from either FAST ENCODING or QUALITY ENCODING (VBR). I have been using the QUALITY ENCODING, Is it possible that is causing the problems? the VBR? SO i should fix the audio seperate from the video? im gonna DL them Progs and try it out!

[BiZzZzaaR]

don't use compressed audio

What is Compressed Audio? is that like VBR?

[mats.hogberg]

Don't randomly download applications. Spend the time to read and learn instead.
Like said, sync problems are mostly due to VBR audio in the source file. The solution is to extract the VBR audio, decompress it to wav, then use the wav as source for further encoding to DVD audio.
There are lot & lots of guides on AVI to DVD to read under Convert left.

/Mats

[redwudz]

When I get a Xvid or other type of AVI, I drop it into VirtualDub Mod. It will tell you if it has VBR (Variable Bit Rate) audio. If so, I use this method: http://members.dodo.net.au/~jimmalenko/ExtractAudio.htm

You can also check for bad frames while you are there and do any filtering or editing that might be needed. If the audio isn't VBR, then you don't need to do anything with the audio. WAV audio is not compressed, most other formats, like MP3 or AC3, etc., are compressed and use a lot less space than WAV. VBR video is different than VBR audio and shouldn't cause sync problems when encoded.

If you have edited or filtered the file in VDMod, you can also frameserve this to your encoder and you won't have to create a edited version of your file: https://www.videohelp.com/virtualdubframeserve.htm

As I mentioned, you can covert any WAV file you have saved out with ffmpeggui to AC3 and add that in when authoring. In that case, you would encode only the video with TMPGEnc.

Or if you want an easier way for all this, but with a little less control and quality, try ConvertXToDVD or it's freeware version. It will handle most VBR audio. What it can't handle, you can use VDMod to process.

[BiZzZzaaR]

Exellent. What about any of the VirtualdubMOd tools, do i need any of them?

[redwudz]

It depends on the video, and what you plan to do with it, but usually it won't need any filtering or any VD tools.

[BiZzZzaaR]

Im gonna try my 1st video fix today. I'll let eveyone know the outcome![/b]

[BiZzZzaaR]

When I get a Xvid or other type of AVI, I drop it into VirtualDub Mod. It will tell you if it has VBR (Variable Bit Rate) audio. If so, I use this method: http://members.dodo.net.au/~jimmalenko/ExtractAudio.htm

Ok i used this guide to make the audio a wav. file but its does show me how to put it back together. Can i do that with virtualdubmod? how do i get the wav. file back to the video and have it match up?

[BiZzZzaaR]

I'm Lost, Red, You say above you take the wav. and use ffmpeggui to convert to AC3? i thought AC3 was VBR? or is it not?

[greymalkin]

i think you may be confusing compression and variable bitrate.


compression just means the that the data was manipulated in some way in order to make the size of the file smaller. this can be done by degredation of quality (like in mp3) or compression can be done losslessly (like when you use a program like winzip to zip up your word documents..etc.)

VBR means variable bit rate....it is the manner in which a program to encodes data. Variable bit rate means that for each given moment, the bitrate used may change depending on how much is needed. For instance, if I'm shooting a video fixed on a person speaking at a podium, the differences from frame to frame will be very small, so I can get away with a lower bitrate and still have it look ok. On the other hand, if I'm filming a sporting event where i'm whizzing all over the place it will require more bitrate. VBR attempts to conserve space by using what it needs when it needs it. It can have the same effect as compression but is a different animal.

in contrast, CBR or constant bitrate uses a static bitrate for the entire video/audio sequence.

[BiZzZzaaR]

Ok, but right now i have made a wav. file from one of my video's audio. How do i put it back together to be burn ready? in the tutorial redwudz put above, i understood all of it but the very bottom, i dont know how to get the video wizard it is showing.
http://members.dodo.net.au/~jimmalenko/ExtractAudio.htm

[BiZzZzaaR]

how do i add the audio back in when authoring? What s authoring anyway?

[redwudz]

There are several ways that you can deal with the extracted WAV audio. It depends on how you want to process the video when you are finally done with it.

> You can combine it back in with the video (mux) as a WAV
>Or use VDM to convert it back to MP3 CBR (I use Lame MP3 and select the same settings as the original, just CBR instead. You can see those settings in VDM 'File>File Information')
>Or you could convert it to AC3 and mux it back in.

To combine it with the video in VDM: In 'Streams>Stream list', click 'Add' to add it. Click on the new audio and move it up to the top of the list. Click on the old audio and then 'Delete'. This will not damage the old audio. Click on the new audio, then 'Full processing mode'. Now if you wanted to just add it back in, click 'OK' and you are done with the audio. In 'Video', select 'Direct stream copy' and then 'Save as' and save it with a new filename.

If you wanted VDM to convert it back to MP3 CBR, in 'Streams>Stream list' again, select 'Full processing mode>Compression. Pick your conversion codec. I use Lame MP3. Select the formats as mentioned above to match the original or whatever you want. Click 'OK' , then 'OK' again and you are done with the audio. You can also adjust the volume or the audio offset when you are in the 'Full processing mode'.

That's how to add the audio back in. You can use this new video and audio file as the final version or convert it to MPEG-2 with most encoders. The problem is you will have re-encoded the audio several times, and that's not good if you want to preserve some quality for the final version; I'll assume DVD.

For a DVD, I save out the audio as a WAV as before. If I am going to use it with an encoder that can use elemental streams (Separate audio and video files), such as TMPGEnc encoder, I am done. Just select the video and the new WAV for the audio and encode. TMPGEnc will give you MPEG-1 Layer2, which is not fully DVD compliant and uses more room than needed for your quality of audio. You can use a AC3 plugin, but I use ffmpeggui and convert separately.

If I am going to use a all-in-one program like ConvertXToDVD, I mux the WAV audio back with the video in VDM. ConvertXToDVD will accept WAV audio, so you don't have to process the WAV any further.

When I plan to use ffmpeggui to convert to AC3 audio for a DVD using TMPGEnc encoder, I use a slightly different method. I encode only the video in TMPGEnc. Make sure the finished file size leaves enough room for the AC3 audio and the authoring files. Figure maybe 200MB for the authoring files. Add that to your AC3 file size and subtract that from the final size of your encoded video. Then it should all fit on the DVD. When that's done, I select the new MPEG-2 video in TMPGEnc DVD Author, and select the new AC3 for the audio. Then I author the files to DVD and burn.

I've never had sync problems with any of the above methods unless the video or audio is messed up in the original file. Dropped frames, missing audio, corrupted audio or video has to be fixed prior to any conversions. Watch out for improper audio offsets, video and audio lengths not matching. In other words, the video and audio have to be in sync before converting to DVD.

These are just my methods. A lot of different ways to arrive at the end product. The all-in-one converters like ConvertXToDVD work fine in most cases if you give them a good file to work with. When the file is messed up, you may have a lot of work ahead of you to fix it.

EDIT: 'Authoring' is the creation of the DVD file structure, including menus, chapters, etc. See 'What is' DVD to the upper left.

[BiZzZzaaR]

Wow i am confused. so do i want the audio to be AC3 if i am making a DVD? I use Nero 7 to make my dvds thats the only program i know how to use right now!

[redwudz]

Sorry, that's a lot of information.

I have never used Nero to create a DVD, just to burn one, so I'm not much help there. AC3 is part of the NTSC (US) standard for DVDs, so Nero should accept it. In general, Nero is not a great program to do much more than burn discs. If you are using it to encode and author, you may have problems at times.

I would recommend a separate authoring program. TMPGEnc DVD Author is the program I use most often. There are also freeware authoring programs like DVDAuthorGui.

Once you have the encoded MPEG-2 and the audio files, you just drop both into TDA and create your menus, etc. It can also burn the DVD when done. It has a trial period to test it out.

[BiZzZzaaR]

OK When i go to use TMPGEnc and i put the video file and audio file in. i get this error. [ Can't Load "P3Package.dll" ] I dunno what that means, but it doesnt let me convert the files!

[DarrellS]

Since you are using VirtualDubMod, in VirtualDubMod, open your AVI file > Click the Streams button > Click on Streams List > Disable Source Audio > Click the ADD button and choose your Saved Wave file and Click Open > Right Click and choose Full Processing Mode > Right Click and choose Compression > Choose Lame > 44100 Hz 128 kbps CBR, Stereo > Click OK > Click OK.
Choose Video > Direct Stream Copy > Save as

I use this Guide for fixing VBR Audio. If the length of the Saved Wave matches the length of the Video then I skip Steps 6 through 8.

Tools needed...
GSpot
VirtualDub (all versions except VirtualDubMod. VDudMod will work but steps aren't the same)
Goldwave

https://forum.videohelp.com/viewtopic.php?t=300624&highlight=

[Ephemar]

To combine it with the video in VDM: In 'Streams>Stream list', click 'Add' to add it. Click on the new audio and move it up to the top of the list. Click on the old audio and then 'Delete'. This will not damage the old audio. Click on the new audio, then 'Full processing mode'. Now if you wanted to just add it back in, click 'OK' and you are done with the audio. In 'Video', select 'Direct stream copy' and then 'Save as' and save it with a new filename.

Hello!2 things I don't get:
1st: Click on the old audio and then 'Delete' Once I click stream list it has the video and then I select the AC3 I made.Move it up but then I can't understand where to find the old audio.I have 2 files:Video (I assume with the old audio in it) and the ac3 file.How can I delete the old audio wich I can not see?

2nd:Since I couldn't find the old audio ,I clicked on the new audio, then 'Full processing mode' then clicked OK.Then 'Direct stream copy' and 'Save as'.Then it gives me an error saying : ''No audio decompressor could be find to decompress the source audio format''

When I choose WAV and not AC3 it has no problems.
My goal is to join AC3 with the video and convert it to DVD with ConvertXtoDVD and hope that it will not have any sync problems.Am I thinking right here?

[mats.hogberg]

The top result when googling for
Can't Load "P3Package.dll"
turned up this:
The most common reason why people get this message is because they don't extract all files into one folder! You have to make sure that you have them extracted.

Another Reason why this happens is because people are running TMPGEnc from shortcuts they have made to it on their Desktop. Try running it from its exe file!

/Mats

[DarrellS]

Why are you trying to put an AC3 file into Virtualdub? ConvertXtoDVD will convert the audio to AC3. If you're going to convert to DVD with ConvertXtoDVD then you might as well leave the wave file uncompressed.

You guys need to read some guides and pick one that seems easy enough instead of trying 50 different ways and confusing yourself and anyone else that might want to help.

It helps to learn the basics before trying to jump into advanced video editing and if you're gonna be downloading videos off of file sharing networks that are going to give you sync problems then you ought to invest in a DivX player that will play them the way they are instead of spending days or weeks trying to convert them to DVD.

[redwudz]

Ephemar, sorry to make it sound confusing. How you deal with the audio depends on what the final format will be and what programs you will be using. In your case, just mux the WAV back into the video with VirtualDub Mod, save it with Full processing with the audio and Direct stream processing with the video and feed the resulting video to ConvertXToDVD.

The AC3 conversion is just used if you want to use a stand alone encoder like TMPGEnc encoder to process the video only to MPEG-2. Then when you author it to DVD you add in the AC3.

[Ephemar]

Yes guys I know that and I'm really sorry to bug you,but redwudz as you know from the post I opened I did mux the wav and convert the file with ConvertXToDVD and the result was AUDIO SYNC PROBLEM! I'm not trying to make my life miserable by searching 100 different ways to make a dvd here.Sorry again

[redwudz]

OK, sync basics.

Two main common types of sync problems: The sync is offset the same throughout the video. Or the sync gradually gets worse as the video plays.

The first one can be corrected by offsetting the audio. This can be done with VDMod in 'Streams>Stream list>Full processing>Interleaving>Audio skew correction. The hard part is determining the offset.

The second one is usually caused by the audio and video lengths being different. You will have to adjust one or the other to match. The problem may be caused by corrupt video or audio or missing video or audio within the file. It can also be caused by bad editing. Some of these problems can be detected in VDM by scanning the video stream for errors.

You can also have a combination of both sync problems, and that can be very difficult to fix. Just because a video plays in it's original format doesn't mean it will do the same after conversion to MPEG-2. A player can 'buffer' over missing frames and audio lapses in the original video without much notice. But encoding needs a error free file.

Check the original file for errors and audio and video length. VDM should be able to do both. You have to determine where the sync error is occurring. My guess is the original file, not after the WAV or video conversions. You especially have to watch out for VBR audio when encoding to MPEG-2.

That's the basics, anyway. There are likely other causes of sync problems. Doing framerate conversions from PAL to NTSC can cause problems also. If someone did the file conversions improperly, which is not uncommon with videos from the net, it gets complex. When they are complex, I usually just dump the file and give up to save the frustration.

[BiZzZzaaR]

Since you are using VirtualDubMod, in VirtualDubMod, open your AVI file > Click the Streams button > Click on Streams List > Disable Source Audio > Click the ADD button and choose your Saved Wave file and Click Open > Right Click and choose Full Processing Mode > Right Click and choose Compression > Choose Lame > 44100 Hz 128 kbps CBR, Stereo > Click OK > Click OK.
Choose Video > Direct Stream Copy > Save as

I use this Guide for fixing VBR Audio. If the length of the Saved Wave matches the length of the Video then I skip Steps 6 through 8.

Tools needed...
GSpot
VirtualDub (all versions except VirtualDubMod. VDudMod will work but steps aren't the same)
Goldwave

https://forum.videohelp.com/viewtopic.php?t=300624&highlight=

OK i do not have a streams Button in my Vdubmod. i only have a FULL STREAm COPY button.
also i cannot find a streams list or a disable source audio. Maybe i dunno where to find it. Also right clicking doesnt do anyting im my Vdubmod.
Can it depend on the version being used. Right now i am using "Virtualdub 1.6.14 (build 24415/release)
I understand pretty much how to do it, i just cant find the options!

[Ephemar]

redwudz I REALLY appreciate your help and others's also.Problem solved for me! Solution is called Super DVD Creator 8.5! It converts any file to dvd WITHOUT ANY sync problems at all!!Just select the video source and let it work!
Thank you all for your valuable time

[DarrellS]

OK i do not have a streams Button in my Vdubmod. i only have a FULL STREAm COPY button.
also i cannot find a streams list or a disable source audio. Maybe i dunno where to find it. Also right clicking doesnt do anyting im my Vdubmod.
Can it depend on the version being used. Right now i am using "Virtualdub 1.6.14 (build 24415/release)
I understand pretty much how to do it, i just cant find the options!

Perfect. I assumed you were using VirtualdubMod since that is what everyone was recommending and you keep referring to. That's where all the confusion was coming from.

Just follow the guide that I posted and you'll be in business since it was made for the version that you have.

https://forum.videohelp.com/viewtopic.php?t=300624&highlight=

Under Virtualdub > Audio > WAV Audio (don't worry about disabling any audio files)

IMO, VirtualdubMod is for advanced video editing and the regular versions are alot easier to use. I rarely use VDubMod and regulary use Virtualdub 1.6.14 and Virtualdub-MPEG2 which is just like the regular Virtualdub with the addition of MPEG2 support. It will also handle WMV.