[golinux]

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.

[golinux]

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.

This post has been edited by sisterscape: 29 January 2007 - 04:48 PM

[gdanski]

That's amazing to me! I wonder.... if we took an unedited file and extracted the audio, add it as the background track, mute the native track (as you have described).... and then immediately render it as a new mpeg file... would this create a file that no longer had audio sync issues and that could be successfuly used for editing in our normal way? If you try this, PLEASE let us know the results. (It will be a while before I can try this as I'm on some other projects at the moment.)

[golinux]

gdanski, on Feb 4 2007, 08:07 AM, said:

That's amazing to me! I wonder.... if we took an unedited file and extracted the audio, add it as the background track, mute the native track (as you have described).... and then immediately render it as a new mpeg file... would this create a file that no longer had audio sync issues and that could be successfuly used for editing in our normal way? If you try this, PLEASE let us know the results. (It will be a while before I can try this as I'm on some other projects at the moment.)

First, let me clarify that my original captures never had a sync problem. It only occurs after DVDBuilder encodes a video whether from a VW production or an output to mpg or avi.

My tests have shown that muting the native track and adding it to the backgroud track only works if it is done during the editing process BEFORE processing in DVDBuilder. The DVDBuilder output will be in sync if it is done during editing but if you re-edit the "fixed" version and encode again with DVDBuilder, it will get out of sync again. If you find anything different, let us know.

[golinux]

After playing with this for a while, I can confirm that putting the native audio into the background track does indeed solve the syncing problem - I just successfully burned an ISO of three ~24 minute segments using this method.

Here's a summary of the process:

1. Edit the video (in this case a 24 minute show) and render to an mpg at best quality. The audio may or may not be in sync at this point but that can be fixed (see #4). Note: any video editing done after this point will screw up the sync with the background track.

2. Save the proxy_xxx.mpg.wav file and name it whatever. This will be used as the background track.

3. Put the .wav into the background track and spot check to see if it is in line with the video. Of the three segments I just processed (all slightly differently) one was in sync and two weren't. Mute the native audio.

4. To fix the ones that were out of sync, I worked in Audacity and increased the speed to 0.040. Editing the audio track separately also allowed for tweaks not possible within VideoWave.

5. One surprise benefit from doing it this way iwas the burn time. DVDBuilder has always taken about 1.75 hours to render a similar ISO. The one I did today using this workaround, rendered in about 15 minutes. The edits/cuts were also smoother.

I'll report back if I find further improvements.

This post has been edited by sisterscape: 08 February 2007 - 06:35 PM

[golinux]

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.

[grandpabruce]

sisterscape, on Feb 12 2007, 10:13 AM, said:

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.

[Merv]

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.

This post has been edited by Merv: 12 February 2007 - 10:49 AM

[james_hardin]

grandpabruce, on Feb 12 2007, 11:27 AM, said:

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.

[ml]

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.

[golinux]

I WOULD JUST LIKE TO CONFIRM THAT THIS LATEST FIX IS WORKING FLAWLESSLY.

Now that I have a system going, I am moving quite quickly through the entire series (I have almost 60!). Ahhhh . . . the pursuit of perfection . . .

The problem with splitting to resync is that the audio sometimes would drop for a frame or two and the video might jiggle a little. This way, the audio is seamless and in sync and the video is very smooth.

James . . . even with defragging etc. things were ALWAYS out of sync.

FWIW, I am editing mpg and outputting to mpg which might be why this happens.

And BTW, I don't ever do chapters - there's no need. Just one episode per project.

Thanks for the feedback, guys.

[james_hardin]

sisterscape, on Feb 12 2007, 05:13 PM, said:

I WOULD JUST LIKE TO CONFIRM THAT THIS LATEST FIX IS WORKING FLAWLESSLY.

Now that I have a system going, I am moving quite quickly through the entire series (I have almost 60!). Ahhhh . . . the pursuit of perfection . . .

The problem with splitting to resync is that the audio sometimes would drop for a frame or two and the video might jiggle a little. This way, the audio is seamless and in sync and the video is very smooth.

James . . . even with defragging etc. things were ALWAYS out of sync.

FWIW, I am editing mpg and outputting to mpg which might be why this happens.

And BTW, I don't ever do chapters - there's no need. Just one episode per project.

Thanks for the feedback, guys.

You may feel like you were alone here, but a glance indicates 175 folks have read this Topic!

I did not mean to sound like I didn't think you were having sync issues, you wouldn't be doing this if you weren't!

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.

[golinux]

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



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.

[Jjjj]

sisterscape, on Feb 12 2007, 08:13 AM, said:

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 captured our Christmas program, an avi file. If I do not cut it about every 5 min it is off sync after I render. Then after rendering small glitches are in my final production. I cannot live with the off sync and need to find a way to not get the glitches.

I think you are describing my problem. I found that cutting up my video which is an hour long did solve the sync problem. Then when I looked at the preview of my ISO file I heard these hiccups. Oh, no. I do not understand how to fix my video file from DVD builder by putting it into an audio editing program – is this in Roxio?

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.

I really hope that I can understand your answer because I am working on a project that covers 20 years of excellence of someone who is retiring and I am making the DVDs.

Your help will be much more than just appreciated.

Jjjj

[golinux]

Hi Jjjj,

If you removed the 'voids' and it synced up, it sounds like you're doing things right. That's GREAT!! I have been suffering with this since I started editing video and it's taken a long time to figure out how to fix it.

You might not need to split the video as often (or at all) using this fix. I edit once to create the final audio track, then I edit to remove any bad frames or other visual warts, and finally output a final silent version to which I add the edited BG track and use for final burning to ISO.

I don't know if there is an audio editing program in Roxio other then the audio trimmer in VideoWave. Someone please enlighten me. I am used to working with Audacity for audio editing - it's freeware and quite good - so that's what I use.

Hope your project will be glitch-free!!

[grandpabruce]

sisterscape, on Feb 15 2007, 11:01 PM, said:

Hi Jjjj,

If you removed the 'voids' and it synced up, it sounds like you're doing things right. That's GREAT!! I have been suffering with this since I started editing video and it's taken a long time to figure out how to fix it.

You might not need to split the video as often (or at all) using this fix. I edit once to create the final audio track, then I edit to remove any bad frames or other visual warts, and finally output a final silent version to which I add the edited BG track and use for final burning to ISO.

I don't know if there is an audio editing program in Roxio other then the audio trimmer in VideoWave. Someone please enlighten me. I am used to working with Audacity for audio editing - it's freeware and quite good - so that's what I use.

Hope your project will be glitch-free!!

Sound Editor is the audio editing program in the Roxio EMC suites.

[Jjjj]

Here is my dilemma:

While editing my sound is smooth. While previewing prior to burn my sound is smooth.

My glitches are in my ISO file so I have no control by then. I have actually played with marking the time for a glitch and cutting it out duringn editting but then a word in the song is missing. I have defragmenter, closed background programs, etc. dedicating my computer to the video for rendering and nothing seems to help. I even tried burning at a GOOD quality instead of BEST. No help here.

You are so right about the in sync success. That was a biggy and I am thankful for it.

If you have any more ideas, please share.

Thanks.

Jjjj

[golinux]

Jjjj, on Feb 16 2007, 10:23 AM, said:

Here is my dilemma:

While editing my sound is smooth. While previewing prior to burn my sound is smooth.

My glitches are in my ISO file so I have no control by then. I have actually played with marking the time for a glitch and cutting it out duringn editting but then a word in the song is missing. I have defragmenter, closed background programs, etc. dedicating my computer to the video for rendering and nothing seems to help. I even tried burning at a GOOD quality instead of BEST. No help here.

You are so right about the in sync success. That was a biggy and I am thankful for it.

If you have any more ideas, please share.

Thanks.

Jjjj

FWIW, my sound is also smooth while editing or previewing prior to burn. To solve the ISO hiccups you need to separate the sound from the video and edit the audio track separately.

Try this. Output a "basic" edit to mpg (or maybe avi in your case) just for the purpose of creating your final audio track. Do not make any edits but to the scene order and length etc. that you want in the final version. Do not try to correct any audio hiccups or small (single frame) video blemishes here.

Start a new production using this output. Then go to your audio proxy file and copy the audio track somewhere to work on repairing the glitches. I always rename the audio file and put it in my working folder.

Then mute the native audio and put this reworked, renamed audio file into the background track of the final version of your video. The tracks MUST be separated when burning to ISO. If you rejoin them prior to burning, the glitches will reappear.

Sorry if I am repeating myself but the process to fix this is a bit complicated . . .

grandpabruce, on Feb 16 2007, 08:11 AM, said:

Sound Editor is the audio editing program in the Roxio EMC suites.

Ah, I see it now under tools. Thanks. I'll probably still use Audacity though because I'm used to it.

This post has been edited by sisterscape: 16 February 2007 - 09:01 AM

[Jjjj]

sisterscape, on Feb 16 2007, 09:00 AM, said:

FWIW, my sound is also smooth while editing or previewing prior to burn. To solve the ISO hiccups you need to separate the sound from the video and edit the audio track separately.

Try this. Output a "basic" edit to mpg (or maybe avi in your case) just for the purpose of creating your final audio track. Do not make any edits but to the scene order and length etc. that you want in the final version. Do not try to correct any audio hiccups or small (single frame) video blemishes here.

Start a new production using this output. Then go to your audio proxy file and copy the audio track somewhere to work on repairing the glitches. I always rename the audio file and put it in my working folder.

Then mute the native audio and put this reworked, renamed audio file into the background track of the final version of your video. The tracks MUST be separated when burning to ISO. If you rejoin them prior to burning, the glitches will reappear.

Sorry if I am repeating myself but the process to fix this is a bit complicated . . .
Ah, I see it now under tools. Thanks. I'll probably still use Audacity though because I'm used to it.

There are no flaws in my sound before burning. Are you saying to take a flawless audio file and some how burn it to an ISO file, mute the original native audio in the original production and put the audio.ISO file with this ISO file. Wow I do not have a clue how this could be done. Can you combine two ISO files? How?
Jjjj

[golinux]

Jjjj, on Feb 17 2007, 06:41 PM, said:

There are no flaws in my sound before burning. Are you saying to take a flawless audio file and some how burn it to an ISO file, mute the original native audio in the original production and put the audio.ISO file with this ISO file. Wow I do not have a clue how this could be done. Can you combine two ISO files? How?
Jjjj

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.