How To Fix Gradual Sync Problems

[Phat J]

sorry i havent checked this forum in a loonnngg time, but anyway ppl are saying sound forge is too expensive, u can do this with other possibly cheaper audio programs like cool edit or gold wave, but i find sound forge is the best because it can load the mp2 file (step 4 in my guide) directly without decoding it to wav first.

Daagar:
sometimes soundforge messes up the time like that, i really dont know why it does this, all i do when this happens is adjust the time u need to stretch it, like for ur example:
u need it to be 1:13:06.459 but it comes out as 1:13:06.119
so it was off by 0.340, try increasing the time u stretch it by 0.340
that usually works for me, and yes it can be a pain in the ass

parkan:
thats odd that ur DivX would go off sync by as much as 2 mins and become in sync again, it would be a huge pain in the ass to fix with my guide, it would involve splitting the video and audio streams in to parts and fix them part by part, and if this happens with every movie u convert to DivX, damn
what happens if u seperate the mp2 file from the MPEG-2 video, and encode it to mp3 directly? u may have to decode the mp2 to wav then to mp3. then encode ur MPEG-2 video (without the audio) to DivX video like u were doing before. now with ur mp3 file, get a copy of Virtualdub MP3 and load the DivX video, go to Audio on the top and pick "MP3 audio..." and load ur mp3 file u just made out of the mp2 file. choose direct stream copy under video and audio menus, and save the AVI.
what u are doing is encoding the audio and video streams seperate then muxing the DivX video with the MP3 audio.

[chewychewytoo]

I am having this same problem when ripping from DVD using Smartripper, then I take the audio out of the vob files using DVD2Avi, this is to then use TMPGENC to convert to a DVD ready Mpeg for DVD-R burning to make a back up of the ripped DVD, anyway it does not always end up out of sync, one will work then the next one will not, they are using the same settings except for bitrate maybe when the encoded file will not fit on a DVD-R at higher bitrate so one maybe 4000 the other 4500 bitrate, anyway is this an issue with the DVD2AVI program making the audio incorrect? I am in the process of trying to correct the gradual sync problem but I am not sure if I understand the why, is there a better program to use that will help me prevent this from occurring? Anyway, any more info on why this happens would be great, I am currently trying to fix Kate and Leopold I had this problem with that DVD rip and this was the only one out of 5 or 6 others I recently backed up using the same software and process.
Cliff

[Phat J]

i never ripped a dvd before in my life haha, so i cant help u there sorry

[chewychewytoo]

Well after some trial and error I thought I had the DVD rip properly synced, when I previewed the resulting mpg on the PC is seems fine, but when I play the resulting back up copy on the standalone player it is now out of sync at the beginning of the video... Unless, I fast forward or rewind it during playback, then the audio syncs up, so for now, I am living with it since its not something that happens on all DVD's, but I am wondering if anyone has any ideas on how to fix this, its a pain in the ...

[trekkermaster]

Well, i use quite a similar approach to yours, although, i use the Sonic Vegas software to resynch my sound.

I like it because you can compare your sound stream directly against the video stream. I load both video and sound side by side and drag the sound stream left or right until i reach synch while playing in the preview window, then save to WAV, encode to mp2 and mux... it generally takes about 10 min in most cases to resync gradual drifts (encoding will add about another 10 min)

Anyone have follow the same path, any comment on better solutions?

[pacoreguenga]

Hi fellows!
I've been around this forums for a while. After more than a decade on the TV/Film/Animation/Visual Effects Bussiness and 2 years of research, I decided to start a Pro DVD Authoring Bussiness. I considered budgets (pockets) in Mexico are not as high as in the US, so I thought I could as well compete with major studios. And the fact is, 6 months later, I cannot handle the workload I'm having. First I began capturing at best quality and compressing via software from my uncompressed or DV avi's. Then I had to switch to Realtime encoding for my lower-budget clients.
After considering many cards (I have owned a lot of cards, BTW), I ended with a cheap card named AverTVStudio which works great! (besides my other cards, of course) and Cyberlink's PowerVCR2 Pro.
It works very good, but for DVD authoring, as all of us know, you have to demultiplex a/v streams, and when you do, Audio no longer stays in sync with video.
After many experiments, I came with a solution that does not really satisfy me, but It works.
Searching for another, faster (and easier) solution, I came to this guide...
Surprisingly enough, It's exactly the same procedure Phat describes, except for the fact that my Soundforge version is too old and can't handel mp2 streams, so I go through an additional step: converting mp2 to wav with CDex (shareware).
The only difference is I measure the whole video duration and stretch my audio to match it.
As someone said, soundforge is tricky to stretch to an exact frame, but it works.
This story has to be told because I noticed the DVD rippers out there critized this procedure and found it useless. Well guys, some of us do author LEGAL AND ORIGINAL MATERIAL, which is trickier than just ripping another people's work.
By the way, I learned authoring by ripping commercial DVD's.
Pro Authoring courses cost as much as $5000 dollars here, and I've never ever really needed a course for anything.
I began my career as a pro 3D animator more than a decade ago. I've mastered the ways of Lightwave, Softimage (Irix and NT versions), Maya, Discreet Logic's Paint, Effect, Flint, Flame, Inferno and Smoke, Avid MCX and XpressDV, Digidesign's Protools, Berkeley's Animo, Eyeon's Digital Fusion, and all the Adobe Line of products.
Enough said, I think Phat wrote a really good guide here and we all should appreciate it. (sound forge is cheap in Mexico. It retails in stores for as little as $50 bucks)
(Until someone develops an easier way to convert non-drop frame mpeg audio to drop-frame, at least)

[roguetr]

That's an impressive resume .... anyway

*Note* There may be a solution amongst this drivell

I've been having the audio sync problem for some time ... I haven't used this guide yet but I think it's going to solve the sync problem in all me brak episodes :) ... I'd love to know how to encode reliable divx with tmpgenc ...

I record from TV using powervcr and I generally specify a compliant mpeg type. The mpeg will play perfectly through windows media player, but as soon as any editing is done through tmpgenc, it's all out. Using the bundled editing software with powervcr is next to useless ... yeah the sound is synced but it's jumpy and horrible.

I tried almost everything until I read that tmpgenc doesn't work reliably with mpegs encoded externally. I now hate powervcr for churning out bad mpegs but I figured if windows media player works, then re-encoding to mpeg with direct show through tmpgenc should work ... and it did.

It's increasing my conversion times but what can you do? I can now cut ads out with tmpgenc and from what _I_ can tell, audio sync is fine. Until someone decides to address the incompatibility between the two programs, makes a converter or whatever, using directshow is all I can think of. I've never researched mpegs, I used to think a vcd pal compliant mpeg was a vcd pal compliant mpeg, the incompatibilty could be minor.

To anyone who can't afford the audio software ... I think you're a couple of steps ahead of yourself ... you're looking for the box network ;) or start saving.

[aaronm32]

Question..
How did you open your .mpg file in virtualdub? Mine won't open .mpg's and gives a "Pack Syncronization" error.

[roguetr]

if it's a vcd mpeg ... or is a renamed dat file, run it through something vcdgear mpeg->mpeg or dat->mpeg ... then try ... or re-encode it first using tmpgenc. I've had no problems opening any type of file under vdub. If neither of those work or you can't be bothered re-encoding, try using dvd2avi ... to frame serve the mpeg. That got me through some faulty mpegs in the past.

[Nelson37]

Good Guide.

Some info for the ATI users, I have been trying for almost 2 years to cut ATI mpgs and maintain audio synch, I've tried everything except Womble and nothing works. From what I can determine, its a combination of ATI's non-standard file format and VBR encoding. Using CBR seems to help, especially if you demux and remux the file. But CBR doesn't give a decent file size, so you gain nothing for real-time encoding.

The only reliable way I have found is to demux the file, re-encode audio and video after frameserving and editing, then remux.

The "Pack Synchonization Error" in Vdub means it is an MPG-2 file, MPG-1 files open fine, I think MPEG2DEC.dll will fix this

[roguetr]

This makes sense to me:

- if the video time is larger then the audio time, then u will
stretch (make longer) the audio by the difference

- if the video time is shorter then the audio time, then u will
compress (make shorter) the audio by the difference

-------------------------------------------------------------------------
But isn't this a contradiction?

2. take the initial time and:
- add the difference to the initial time if the
video comes before the audio. (make audio longer when already longer?)

- subtract the difference from the initial time if the audio comes before the video. take this number and enter it as the Final Time (make audio shorter when already shorter?)

Sorry but this is the first time I've used this method ... and although logic helps ... it's not always reliable. I'm assuming the guide is incorrect ... but I am probably wrong.

[VCDman525]

Do not ask for warez!

-TGPO

[Acidagent]

Please see my how to. I do believe i've sorted it all now.

[NeoMorph]

As I didnt know this fix I found a way to do it on my own... it's pretty similar to this but actually is simpler...

1. De-multiplex the sound out of the file... (I used mpeg-vcr from Womble.com)

2. Convert the mpa file produced into a wav file (I used Winamp)

3. Using Dr DivX select the original mpg file as the video source.

4. When it asks whether to use the audio track in the mpg say no and click external audio file... point it to the wav you extracted.

5. Make your Dr DivX encoding solutions (dont seem to affect the sync from now on - I used slow encodes all the way though) and start your encode.

The result is a perfectly in sync avi file...

Way I found this fix was to setup a load of alternate encodes options on the same input file and ran them overnight and then checked which test runs produced a decent sync... and it was using the external wav that produced the only decent output file.

I still dont see how it could fix it but it does... Does anyone know WHY it fixes it because I'd love to know

[bendy]

Hey all, Newbie authorer here looking for some help.
I'm authoring my first DVD on DVD Maestro and I'm having this gradual out of sync problem. The probelem stems from the fact that when I import the assets into Maestro the timecodes that register for the audio and video files are off. For some reason it is calculating the timcode at 30 FPS even though the file is 29.97 and lists as 29.97. In DVD lab there is an option to check the bitrate which fixed it there, but sdaly not in DVD Maestro. I'd really appreciate any help, Thanks!

[reboot]

I use this method. Goldwave, instead of Sony
http://club.cdfreaks.com/showthread.php?s=&threadid=59487