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Audio sync solution?


golinux

Question

I recorded a show with my set top recorder and for some reason one of the chapters clipped about 50 seconds off the end. I had an older dub from VHS tape and spliced in the missing 60 seconds and it looks great. But now to my 'discovery' . . .

 

The audio sync was off after the bungled chapter transition to the end of the show, maybe 10 minutes. Here's what I did to fix it. First, I edited the .wav file in Audacity then added it to the background audio track and finally muted the native audio. It took a bit to get it in sync but finally managed.

 

What is interesting is that the background audio remained in sync with the video to the end of the show even after creating an ISO with DVDBuilder. In the past, the native audio has always started to come 'unglued' from the video after about 4-5 mintues requiring splitting every production into smaller segments.

 

This makes me wonder (haven't tried it yet) . . . if the native audio were always muted and the audio track added as background would the tedious process of multiple splits unnecessary?

 

I'll report back as soon as I play around with it a bit more.

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Which brings up the next problem..

but which voids should be remove since they are of different lengths ???

I find the first really obvious void and work backward and forward at regular intervals from there. The other 'imitation' voids were never noticeable as they were native to the original track.

 

Besides, (if any voids are left behind) I can't stand the noise the 'voids' make during playback, (they all make a noise) they sound really terrible on a full 5.1 system using prologic (or any DSP) at full blast, (I'm transferring short live musical performances) and DD-2 Stereo mode is not any better.

After careful editing, I am not aware of any hiccups. I have VERY good ears.

 

Looks like this solution is not going to work for me, it is probably fine for other applications. :(

Strange that this isn't working for you. It has always produced seamless results for me.

 

I can't believe Roxio is not able to fix this issue after this many years into DVD/CD authoring. :rolleyes:

In order to fix it they'd have to admit it's a problem. Not likely to happen.

 

I read people still have the same problem with version 9, is this true???

Dunno. I'm dumping Windows for Linux so will have to leave Roxio behind.

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I thought that a screenshot of the audio voids might be helpful so here it is. The cursor is right in the middle:

 

dropout.jpg

 

There is one of these about every minute and 3-5 seconds in the rendered mpg audio. Get rid of them and the audio will be in sync.

 

You can not only see them, you can hear them if you listen closely. There will be a little hiccup in the audio track or a word may sound a bit garbled or 'splattered'.

 

I can't tell you how happy I am to FINALLY have this figured out.

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I captured this file from a DVD that was made by someone else. I was out of town and did not video this program myself and therefore did not capture it from my camcorder to my computer. Jjjj

 

I think you're absolutely right.

 

Encoding matters. Many of the audio/video sync issues are caused by decoding/encoding an mpeg2 file.

 

When you edit that video, you're only making an editing file which links back to the original video that you imported.

 

When you burn to an .iso or DVD, that's when your video is decoded and reencoded and that's where the audio/video sync issues are happening.

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I am going to ask you to PRETENT that I can't follow your previous posts!!!

(this will REALLY not be hard, because I mostly DO NOT)

 

I have TWO projects that I need to clean up, and desperately hope you can help!

 

1. I burned a DVD on my DVD recorder from TV, and transfered these segments each via video capture with Roxio

 

2. I created a project, inserted each of these clips (as insert captured video)

 

3. Saved the project... and then created an ISO file saved to hdd (I almost always do this FIRST, then burn to DVD)

 

4. Once the ISO was created, I use disc copy to create a DVD

 

However... this finished DVD seems to have the audio sync problems!

 

I downloaded Audacity, but don't know how to get to what I need... please help!

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AUDIO SYNC SOLUTION . . . THE NEXT CHAPTER.

 

The method described in my previous post was inconsistent and unreliable so I took it back to the drawing board. Here's what I discovered.

 

When I started to look more carefully at the rendered mpg audio file, I saw a pattern of hiccups - tiny silent spaces of several hundredths of a second that were added during the rendering of the edited file. They occur at regular intervals about every minute plus a few seconds.

 

These silent spaces are cumulative within each panel of a production. When the video is split, the audio gets resynced and the 'voids' start to be added again from this new point. This is why the syncing problem becomes noticeable after 6 or so minutes and is 'cured' by splitting the panel.

 

I went into my audio editing program and removed all of these 'voids', placed the repaired audio into the background track and things synced up consistently.

 

The only exception is when there are inserted images or color panels. The duration of these added images is shortened by the length of time that was added to the preceding audio during the rendering. So to sync things up after an inserted image, some time has to be added to the image duration during the audio editing process.

 

It seems I am talking to myself in this thread but hopefully others will learn from my investigation.

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When you burn to an .iso or DVD, that's when your video is decoded and reencoded and that's where the audio/video sync issues are happening.

And that's exactly when/where splitting the original audio from the video solves the problem!! The encoding process seems to deal with native audio differently than background audio. Even if it was made by someone else, it should be correctable.

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AUDIO SYNC SOLUTION . . . THE NEXT CHAPTER.

 

The method described in my previous post was inconsistent and unreliable so I took it back to the drawing board. Here's what I discovered.

 

When I started to look more carefully at the rendered mpg audio file, I saw a pattern of hiccups - tiny silent spaces of several hundredths of a second that were added during the rendering of the edited file. They occur at regular intervals about every minute plus a few seconds.

 

These silent spaces are cumulative within each panel of a production. When the video is split, the audio gets resynced and the 'voids' start to be added again from this new point. This is why the syncing problem becomes noticeable after 6 or so minutes and is 'cured' by splitting the panel.

 

I went into my audio editing program and removed all of these 'voids', placed the repaired audio into the background track and things synced up consistently.

 

The only exception is when there are inserted images or color panels. The duration of these added images is shortened by the length of time that was added to the preceding audio during the rendering. So to sync things up after an inserted image, some time has to be added to the image duration during the audio editing process.

 

It seems I am talking to myself in this thread but hopefully others will learn from my investigation.

 

I am following, but so far, I have not had audio/video sync problems. But, I haven't done any long videos, lately.

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I am going to ask you to PRETENT that I can't follow your previous posts!!!

(this will REALLY not be hard, because I mostly DO NOT)

 

I have TWO projects that I need to clean up, and desperately hope you can help!

 

1. I burned a DVD on my DVD recorder from TV, and transfered these segments each via video capture with Roxio

 

2. I created a project, inserted each of these clips (as insert captured video)

 

3. Saved the project... and then created an ISO file saved to hdd (I almost always do this FIRST, then burn to DVD)

 

4. Once the ISO was created, I use disc copy to create a DVD

 

However... this finished DVD seems to have the audio sync problems!

 

I downloaded Audacity, but don't know how to get to what I need... please help!

1. If your original clips didn't require any editing, either extract the .wav files or find them in the proxy folder. Copy and rename them whatever you wish and put them with your other project files. Then in VideoWave mute the native audio and place the .wav files you just found into the background track for each clip. This won't require any editing of the audio because no voids have been created yet.

 

2. But if you edited your clips, you will need to output your project to 'video file' to create the audio for the edited version. Then as above, find the .wav file(s). But this time you will need to edit them to remove the voids because outputing to .mpg creates them. Once the files are cleaned up mute the native audio and place the cleaned .wav into the background audio track.

 

Then when you burn to ISO everything should be in sync.

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SisterScape....

 

I know this thread is a bit old but after reading through it, I compliment you on your persistence and your solution.

 

I have ALL the EMC suites since 7 and I have the older adaptec software.

 

I have always had sync issues with my video. That's actually why I kept purchasing the new version of EMC. First, because I was an owner of a previous version there was special pricing available for the new software. Secondly, I kept hoping a solution was provided in the new release but I have always been disappointed.

 

My projects would always preview perfectly but after rendering and actually creating the ISO or DVD, the sync issues would appear.

 

I tried your technique and wha-la.. Thank you.

 

I am hoping that Roxio people may see this thread or one of the Guru's may bring it to the attention of Roxio and they can develop a patch to address this issue on the existing and newer releases.

 

If the problem can be duplicated, and the work around consistently produces the expected results, then there is more to it than defragging, driver updates, DirectX, smaller files, etc, and a fix could be at hand.

 

I bow at your feet ;) Your solution should be sticky'd

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Hi, sisterscape

 

I'm listening. In fact, I have this thread bookmarked for future reference. I still like using V7 even though I now have V9. In 7, I did have audio/video sync problems with some edited mpeg files, but not others. Never did figure out why some had the problem but others did not. So, if I have them again, I will certainly refer to this post.

 

I thank you for the extensive troubleshooting and posting the potential workarounds.

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SisterScape....

 

I know this thread is a bit old but after reading through it, I compliment you on your persistence and your solution.

 

I have ALL the EMC suites since 7 and I have the older adaptec software.

 

I have always had sync issues with my video. That's actually why I kept purchasing the new version of EMC. First, because I was an owner of a previous version there was special pricing available for the new software. Secondly, I kept hoping a solution was provided in the new release but I have always been disappointed.

 

My projects would always preview perfectly but after rendering and actually creating the ISO or DVD, the sync issues would appear.

 

I tried your technique and wha-la.. Thank you.

 

I am hoping that Roxio people may see this thread or one of the Guru's may bring it to the attention of Roxio and they can develop a patch to address this issue on the newer releases.

 

If the problem can be duplicated, and the work around consistently produces the expected results, then there is more to it than defragging, driver updates, DirectX, smaller files, etc, and a fix could be at hand.

 

I bow at your feet ;) Your solution should be sticky'd

I'm so happy to hear that this fix worked for you. I am currently reediting about 30 hours of video using this technique and it has worked every single time.

 

Yeah, I'm persistent alright . . . in constant pursuit of 'perfection' . . . :D

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I did one last test before giving up on version 7, this time rendering the audio as LPCM to see if the different encoding would make a difference.

 

Same issue, :( audio is out of sync and after analyzing the new captured file from this test the wave file again exhibits the audio 'voids', same amount of them also, about one void per minute.

 

well, better (very) late than never :lol:

 

After two years :o I finally got around to mess around with this again, this time using Creator 9

 

I re-did the project all over again using the same footage and same computer, first using videowave and then Mydvd for the menu..

Creator 9 apparently treats 'gaps' that cause out of sync issues differently, the resulting DVD is now in sync but now the video 'jumps' to sync up with the audio, not perfect but better than before..

 

In any case, I think my problem lies with the way the footage was transferred from SVHS...somewhere in my process it went out of whack..

 

Just posted this info in case anyone stumbles into this old post..

 

 

 

 

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I am following, but so far, I have not had audio/video sync problems. But, I haven't done any long videos, lately.

Like GPB, I too am following it but since Defrag and Software render resolved any sync problems, I am having a little trouble seeing the need…

 

In my V7 projects, I had usually set Chapter points at 6 minute intervals, no chapter menus.

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I too am following your process of discovery.

 

I edit mostly DV AVI video from my camcorder and don't have audio/vide sync problems, but eventually I'll get a DVD recorder and what you've discovered will become invaluable to me.

 

Thanks for sharing. :)

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I've read this entire thread, and I find all the information you gathered through experimentation very interesting. Thank you for sharing your findings and solutions.

 

I would like to offer a theory about what is actually going on here -- what is causing the audio sync problem.

 

I used to use another program to edit video. There was a setting that allowed you to compensate for NTSC's framerate of 29.97 fps (frames per second.) This setting was called "drop-frame" timecode. You can read about it here. Basically, it's a method of compensating for the 29.97 fps versus true 30 fps discrepancy. Drop-frame timecode drops frame numbers 0 and 1 of the first second of every minute, and includes them when the number of minutes is divisible by ten.

 

I suspect that Roxio is not taking this into account somewhere in their software. If they are rendering the video at 30 fps, but keeping the audio at the original clock speed (which is synched for 29.97 fps,) this would cause a 3.6 second audio mismatch per hour of video. (Or, maybe the opposite is happening.) I haven't done any measurements, but I would estimate this to be about what I have experienced when creating a DVD from captured DV (NTSC) video.

 

Strange about the "hic-ups" you found in the audio. Maybe these small sections of silence are a (poor) attempt to compensate for differing frame rates?

 

Hopefully, Roxio can address this issue in an update/bugfix. But, (and everyone please forgive my cynicism) since many posters to this thread have experienced this problem in previous versions, I won't hold my breath.

 

Thanks again for your efforts.

 

-Josh

P.S. If James Hardin happens to read this post: Please understand that just because you don't see a large number of posts about a certain problem, this does not mean that many people aren't having the problem. I'm referring to your earlier post on this thread, in which you said (as you seem to in many of your posts), "This may be the procedure that a few users like yourself will have to go through but it is way beyond what the majority need to do to get things running correctly."

 

Maybe the "majority" of users haven't yet used the feature in question. Or, maybe there are more listeners than speakers in a particular thread. I find your frequent, Roxio-apologetic responses frustrating. They only make you seem like a Roxio PR spin doctor, and they rarely, if ever, offer any help with the issue at hand. Please, for the sake of usefulness and legitimacy in this forum, stop trying to smooth-over real problems that users are experiencing. I enjoy using and even recommend MC9, but it's far from perfect.

 

 

I didn't read the entire thread again and don't know how I missed this post. The audio/sync sympton affects all video editing software that I have seen. I have never had that problem but have read posts in these forums and forums (non-Nero sponsored) that discuss problems with audio/sync problems with the Nero software.

 

And I agree with you, EMC 9 is not perfect.

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Well, I experimented some more. After replacing a 13+ minute segment of the native audio with an edited version of the proxy .wav file in the background track, the audio remained in sync with the video! The native audio would have been badly out of sync after that amount of time.

 

It's kind of a tossup whether splitting into smaller segments or replacing the native audio is a better way to go - both are a hassle. I guess it will depend on each individual production.

 

In any case, it is another workaround that can be offered to other users with a sync problem.

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No that's not it. I'll try again.

 

Creating the audio track . . .

 

Open your edited production in VideoWave. When it loads the audio track is captured as a .wav file in C:\Documents and Settings\user\Application Data\Roxio\VideoWave7\Proxy. Copy this file to your working folder and rename it. Edit the hiccups (voids) from this .wav file in an audio editor.

 

What to do with it . . .

 

Mute the audio of your production and place the edited .wav file into the background track. Separating the video from the edited audio will resync them and the hiccups have now been removed. Note that if you have any image panels in your production you may have to adjust the timeline of the audio a bit during those images.

 

How to burn it . . .

 

Add the .dmsm file that VideoWave creates into your DVDBuilder production and burn to ISO. Everything should now be in sync and without hiccups.

 

 

I never found the Proxy file using the path that you gave but I did find that I could Extract the Audio so I did that which I am thinking will accomplish the same thing. I am working on it now and will let you know how this works for me.

 

Thanks for all of your help and suggestions.

 

Jjjj

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No that's not it. I'll try again.

 

Creating the audio track . . .

 

Open your edited production in VideoWave. When it loads the audio track is captured as a .wav file in C:\Documents and Settings\user\Application Data\Roxio\VideoWave7\Proxy. Copy this file to your working folder and rename it. Edit the hiccups (voids) from this .wav file in an audio editor.

 

What to do with it . . .

 

Mute the audio of your production and place the edited .wav file into the background track. Separating the video from the edited audio will resync them and the hiccups have now been removed. Note that if you have any image panels in your production you may have to adjust the timeline of the audio a bit during those images.

 

How to burn it . . .

 

Add the .dmsm file that VideoWave creates into your DVDBuilder production and burn to ISO. Everything should now be in sync and without hiccups.

 

 

I've had the same problem with out of sync audio and found this thread with your solution.

 

I captured video from a SVHS to a table top DVD recorder with HDD, this MPEG video file was burned into DVD and then captured into Roxio for a more detailed, precise processing. ( thinking the process would be faster) :huh:

 

Since this is my first time using the ‘Video’ utilities of Roxio (Version 7) I started off with ‘DVD Builder’ for the production, but after rendering the final production encountered the same Sync problem described here.

.

After reading here I started this production again from scratch , this time using ‘Videowave’ instead (edited all clips, added all the transitions, fixed the clip’s audio volume, applied some EQ, inserted ‘second audio’ )reasoning that my previous use of ‘Dvd builder’ was the reason I can’t find the ‘wave’ files under the ‘Proxy’ directory.

 

Well, I’ve since created both a Movie (AVI) and a Video (Mpeg) of my project (using (both ‘DV Camcorder’ and ‘Video files’ options )but still this process is not generating the “Wave” file (under Proxy)needed to edit/cut out the ‘defects’ later to be inserted as ‘Background audio’.

 

Does anyone have any ideas why this is happening now???

 

PS: the funny thing is that I *did* create a short “Test run” project two days ago after discovering this ‘work around” here , and Video Wave did create the Wave file under ‘Proxy’ for that short production , but now I can’t duplicate the process using the full completed production, I’ve been working on this *one* project for days now…. :blink:

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The audio/sync sympton affects all video editing software that I have seen. I have never had that problem but have read posts in these forums and forums (non-Nero sponsored) that discuss problems with audio/sync problems with the Nero software.

 

And I agree with you, EMC 9 is not perfect.

In my quest to get this figured out, I have either trialed or purchased other editing software and this is where I am: (This is a long thread and if I am redundant, I apologize).

 

EMC is the ONLY software that produces the sync problem for me.

 

I own version 7 through version 9 (I do not have 7.5) and the problem exists in all versions (at least for me).

 

It happens in MyDVD (I think? (I know this has been covered)).

 

If I do all my editing in a different software in which all edits, cuts, transitions, etc are complete and output a complete MPG file in which no other work needs to be done (including encoding) and then turn it over to MyDvd to actually make the DVD with menus, I have no sync problems.

 

If I use videowave for the editing, or leave the media file in a state where MyDvd has to do any encoding, for some reason which is eluding me, the finished project has the sync issues if ever MyDVD needs to do ANY encoding.

 

Everything previews perfectly. It is always the finished project which is out of sync. It does not matter if I actually burn the DVD, make a folder set on the HD, or make an ISO file. All suffer the same result if MyDVD has to do ANY encoding.

 

I have worked with SisterScapes solution and it does indeed work for me every time but I have only tried it on three projects. However IMHO, it is a lot of work.

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I'm so happy to hear that this fix worked for you. I am currently reediting about 30 hours of video using this technique and it has worked every single time.

 

Yeah, I'm persistent alright . . .agreed.gifagreed.gif in constant pursuit of 'perfection' . . . :D

 

clap.gifclap.gif

 

cd ;)

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