problems with audio /video synch with megui

[larénion]

Hi, excuse me for my english but I’m french
I have problems with audio /video synch with megui
Here is my procedure :

Dvd decrypter (2.70a)
- Rip the dvd with dvd decrypter and i get some vob files (I use the file mode and choose the vob manually because in IFO mode there are not one big pgc but several small pgc !)
Megui (0.3.1.1017)
- create d2v file and ac3 file with d2v creator
- the ac3 file have 0ms delay mentionned
- Open the d2v file in Avisynth creator
o No change in input DAR
o Auto crop
o Resize (suggest resize)
o Mpeg2 deblocking
o Colour correction
o I check Anime (because it is)
o I check analyse button and let him choose the good filter to deinterlace
o Resize filter « Lanczos »
o I save
- The d2v and ac3 files is charged in megui automatically
- I use unrestricted 2 pass anime toons HQ for the video
- I use NDAAC HE 64kbps for the audio
- I use auto encode and select a file size and a mp4 box and queue
- I start jobs in Queue

The audio and video synch is OK at the beginning of the film but the decalage is progressive along the film. The audio is then before the video at the end of the film.

Please help !

[Sharktooth]

first of all things, let megui auto-update to the latest version (get ALL the updates) and also use a newer ripping program, like DVDFab HD Decrypter.
also ensure the video FPS are correct before encoding.

[larénion]

Hi,
Thanks for your response.
it's OK for MeGui's update
I will try DVD fab today.
But how can I check if the fps is good or not?

[Sharktooth]

there are several ways.
the easier one is to play the avs file in MPC(HC), dub the audio and check if it is in synch.

[larénion]

Hi,
I don't understand "dub the audio"

I use dvd fab (full disk mode because of the several small pgc)
I create D2V file and the avs script.
I play avs script file in MPC HC and the audio/video is not synch (OK at the beginning and not synch at the end), exactly like the mp4 files I have done before.

What can I do?

Thanks

[b66pak]

post your .avs...
_

[larénion]

Hi,

Here is the .avs
--
DGDecode_mpeg2source("C:\Users\Bertrand\Documents\Films\VOB\Tchoupi musicien\dvd fab\FullDisc\TCHOUPY_MUSICIEN_SCN\VIDEO_TS\VTS_01_1.d2v", cpu=4, info=3)
ColorMatrix(hints=true, interlaced=true, threads=0)
Load_Stdcall_Plugin("C:\Program Files\megui\tools\yadif\yadif.dll")
Yadif(order=1)
crop( 0, 2, 0, -2)

LanczosResize(720,528) # Lanczos (Sharp)
#denoise
--

[larénion]

Hi,

I think the progressive audio/video decalage is perhaps due to the type of dvd. My son has several dvd wich contains severals cartoons. Every cartoons lenght is 5min, so we have on the dvd several pgc of 5min and not a big pgc which include all the cartoons.

I try an other cartoons which have one big pgc 50min lenght and i didn't have the progressive audio/video decalage.Just a very small constant decalage.

Thanks you for help.

[Inspector.Gadget]

DGIndex can be used on a VOB that represents only a single 5 minute cartoon and (barring silent leading cells) calculate the audio delay correctly. Try the following AVS Script in MPC (remember to allow ffdshow to decode YV12):

vid = DGDecode_mpeg2source("C:\Users\Bertrand\Documents\Films\VOB\Tchoupi musicien\dvd fab\FullDisc\TCHOUPY_MUSICIEN_SCN\VIDEO_TS\VTS_01_1.d2v", cpu=4, info=3).ColorMatrix(hints=true, interlaced=true, threads=0)
aud = DirectShowSource("C:\Users\Bertrand\Documents\Films\VOB\Tchoupi musicien\dvd fab\FullDisc\TCHOUPY_MUSICIEN_SCN\VIDEO_TS\youraudiofile.ac3", video=false).DelayAudio($)
AudioDub(vid, aud)

Where "$" is your audio delay. Example: If your audio delay is -13 milliseconds, you would use the value -.013 in DelayAudio().

If you still have trouble with progressive desync, there's a problem with your video framerate somewhere; do you perhaps use DGIndex with "Ignore Pulldown Flags" or "Force Film" enabled?

[b66pak]

if its only 5 min .vob then post it...use mediafire or megaupload...
_

[larénion]

Hi,

I will try to understand the response of Inspector.Gadget. Thanks

On ONE dvd there are 13 cartoons 5min lenght (13 pgc when I decrypt) and my vobs files include all the cartoons and are 65min lenght.

I'll come back with results.

[larénion]

Hi,

I try the AVS script in MPC and the decalage is always progressive exactly like before.(I don't touch anything about the YV12)

Please could you clarify: "do you perhaps use DGIndex with "Ignore Pulldown Flags" or "Force Film" enabled?"

Thanks

[larénion]

Hi,

Could somebody tell me how to use "Force film" or "Ignore Pulldown Flags" in DGDecode syntax?

Thanks

[poisondeathray]

Originally Posted by larénion

Hi,

Could somebody tell me how to use "Force film" or "Ignore Pulldown Flags" in DGDecode syntax?

Thanks

I don't think you can with the the built in tool in megui

You can do it manually with DGIndex (not through megui) (video=>field operation)

[larénion]

Hi,
I try with DGindex and use "Force film" or "Ignore Pulldown Flags" but the results was the same. I also had an audio delay at the beginning of the film. What can i do to correct the lenght of video or audio?

On the other hand, I encode other cartoons with have one large pgc when i decrypt. With this kind of dvd, I haven't a progressive but a constant decalage of audio (the audio was late).
I managed to correct it before encode (thanks to Sharktooth): I preview the avs script in MPC and I use the Audio options (audio time shift) to find the correct delay to use in Megui muxer.
For example, in "Robin des bois" cartoon, I use -500ms to have a correct synch!!.

I have some questions:
- Does the problem of synch is due to "deinterlacing method"?
- are there some tools which give the exact length of video and audio which could prevent us with progressive decalage before encode?


Thanks for help.

[poisondeathray]

1) No the deinterlacing method should not cause A/V sync issues
2) You can use mediainfo to determine stream lengths. Gspot or avinaptic may also give you some information

For the delay issue, when you demux the audio, it will have the delay value written in the name. You either implement it into the script with DelayAudio() - See Inspector.Gadget's post above, or directly enter that audio into the megui audio (you will see the delay value change in the box). I would construct a script as above, then test it in a media player for A/V sync. If you are not re-encoding the audio, just enter that value as the delay when muxing.

You might try another source input filter e.g. DirectShowSource()

[larénion]

I understand what i can do if there is constant V/A sync problems.
But if the V/A décalage is progressive. What can I do?
Perhaps modify the video fps? how?
is there a syntax in AVS script creator?

For my cartoons dvd I'll try to find why there is a desync all the same...

Can somebody help me with the decrypt options in DVD decrypter or DVDFab (to perhaps prevent from bad frame...)

[b66pak]

Originally Posted by b66pak

if its only 5 min .vob then post it...use mediafire or megaupload...
_

again...
_

[larénion]

Hi,

I manage to send the vob file to mediafire.

I decrypt just one cartoon (5 min) on the dvd and I compare the vob file and the .avs file create by avs creator in megui. I use VirtualDub. Here is the results:

FICHIER VOB: durée: 0:05:01:280
IMAGE 0: black
image 1: beginning of the cartoon(0:00:00:040)
...
image (last-1): end of cartoons
image (last): black

7532 FRAMES

FICHIER avs: durée: 5:01:280
IMAGE 0: black
image 1: black
image 2: beginning of the cartoon(0:00:00:080)
...
image (last-1): end of cartoons
image (last): black

7532 FRAMES

We can see that in the avs script, the cartoon begin at the image 2 whereas in the vob file it's at the image 1 and the delay beetwen the two image is 40ms I think.

What do you think about that?

[Sharktooth]

... where's the link?