audio delay correction in meGui ?

[Hobojobo]

How can I tell meGui to take the audio delay value from the audio file name automatically to correct the delay?
I am quite sure it worked before.

:stupid:

[Sharktooth]

it already does it.

[Hobojobo]

I see.

I thought, I would see the corrected delay in the Audio Config window. When I load an audio file, let's say "VTS_01_1 T01 2_0ch 192Kbps DELAY -8ms.ac3", I do not see the option "Delay Correction" ticked with the right value filled in (-8ms).
But it is greyed out.

Does that mean the correction will be done anyway?

[Sharktooth]

yes... it will be done automatically.

[JarrettH]

ok thanks this answers my question too

btw....when i create my aac files they come out almost 2 minutes shorter if you could look at my thread :scared:

http://forum.doom9.org/showthread.php?t=119577

[Hobojobo]

Which software do you use for play back your aac audio files?

MPC does not get it right:
For example:
duration in MPC: 2h 22min 15sec
duration in Winamp: 144min 30sec = 2h 24min 30sec

When I play the movie in MPC the duration is 2h 24min 30sec.

[Shandra]

Good old search function ;)

Aside from Sharktooths answer I am still a bit confused.
Does the delay (if present in filename) will be processed regardless of selected options, or are there some exceptions (avisynth y/n, source-target format, etc.)? What if the filename incorporates a delay and out of confusion one still ticks the add delay and enters the number (MeGUI 0.2.4.1026)? Does this mean the delay will be added twice, or is the tick to delay an override to autodetect?

And another topic I stumbled across (but also for Belight, etc.) - If the App takes care of the Delay and generates the output filename, wouldn't it be a good idea to either cut the former mentioned delay or to set it to 0 (Still no problem in naming the file myself, but was something that always tickled my backbrain)?

[graysky]

Was wondering this myself since there is an option in the audio section>config>delay correction. Default is unchecked. As well, there's another check box to the right with a minus sign in front of it. I'm assuming you check that if there's a neg. delay.

I don't see how this occurs automatically if the box is unchecked by default and the default is 0 ms.

Anyone?

[bananacreamandpeca]

I also have a audio-delay question wich relates to Megui.

When I use the MKV-muxer and manualy put a delay say -194 and mux.
The log says this:

-o "C:\HE-MAN I\chapter 3\three+audio.mkv" -A -S "C:\HE-MAN I\chapter 3\three.mkv" --language 0:eng -a 0 -D -S "C:\HE-MAN I\chapter 3\VTS_01_PGC_01_1 T01 2_0ch 192Kbps.mp3" --no-clusters-in-meta-seek
successfully started encoding
Processing ended at 5:13:15

So can you tell from the log, if Megui used that delay when
muxing or not?

I ask this because I was confused when playing back the
muxed output.
Any mistakes were too short to notice, but still.

And yeah yeah, I know the input doesnt have a "DELAY -nnn"
in the filename.
But that's because I stripped it before using BeLight.

[Shandra]

Mh... can't say for sure :( I am always using MKVtoolnix for muxing of AV encoded in mp4 to mkv. And the commandline there incorporates a --sync streamID:delay flag if I enter a delay correction (and as mmg does this on automatic if the filename includes the info I hope again that the GUIs for encoding audiotracks would correct the original demuxed filename if they applied a correction - would safe time and confusion ;) )

[Shandra]

Just to answer my semi-questions some posts above (just in case someone does a search and gets confused).
As I was testing MeGUI and Aspect Ratio Calculation on a short clip yesterday I also went for this delay confusion ;)
So I created a small 5 seconds of white noise stereo wav in audacity, named that file with various delays (DELAY 0ms, 1000ms, 2000ms and -2000ms) and let those be processed by MeGUI. Then I checked the Result in Foobar - and I got 3sec, 5sec, 6sec and 7sec playtime. Then I also checked again on one file with ticking the delay box and entering a value by hand, this worked as an override and not in addition (as I feared it may) ;)
So, if one wants to keep the delay and enter it when muxing the delay box shoulda be checked with a 0ms delay, or the filename could be altered temporarily for the encode.

[Hobojobo]

I am still a bit confused.
For example:
I have got a video file, and 2 ac3 audio files.

video.mp4
audio1 DELAY -500ms.ac3
audio2 DELAY -500ms.ac3

I want to transcode the 2nd audio file to aac.
megui does it for me via NeroAacEncoder.

The result file is named audio2 DELAY -500ms.mp4

Then megui muxes the video, the ac3 file, the aac file into a container.

Where does the audio delay correction take place?
During audio transcoding or during muxing?

Would it be during audio transcoding the resulting audio file should be named differently, shouldn't it? Like audio2 DELAY 0ms.mp4

[Shandra]

Would it be during audio transcoding the resulting audio file should be named differently, shouldn't it? Like audio2 DELAY 0ms.mp4

Thats what I meant with "If the App takes care of the Delay and generates the output filename" ... If the Filename incorporates a DELAY it is taken into account whence encoding with MeGUI, or with BeSweetLight (if not overridden), or whatsoever... but those Apps are not changing the "Automatic" derived Filename in complience with their "Fix" to the Offset...

So if you put a DELAY +-X File to MeGUI encoding - what you will get is a +-0ms File, but with a Filename that stays true to the original name... Tick the delay box, enter 0ms delay and you will get a file that stays true to the filename.
IMHO that is a problem, because if you MUX yourself audio and video with - lets say MKVToolnix - that GUI will add the delay refered to in the Filename, and therefore be wrongly offset by the name. As I am always muxing manualy I do not know what will happen for automuxing, or muxing in general with MeGUI. I simply stick to "mmg" - and there I know now to either strip the DELAY from the filename, or to deactivate the automatically detected Offset.

I do not know what happens for MeGUI and muxing therein...

[Hobojobo]

There is another problem.
Like in my example:
I want to take 2 audio streams. And I want to transcode one stream to whatever.
The stream which is transcodes, has got a corrected delay and still the original delay in its name.

How can megui distinguish the delays of the both audio files. One of them is definitely wrong.
Perhaps megui takes that into account without telling us.
:-)

[Shandra]

The stream which is transcodes, has got a corrected delay and still the original delay in its name.

How can megui distinguish the delays of the both audio files. One of them is definitely wrong.
Perhaps megui takes that into account without telling us.
:-)

Good queston... but from first instinct I would say... Filename incorporates Delay, and if you tanscode with MeGUI that is taken care of, you would end up with the inversed delay of the filename...

Maybe now it is time that one of the gurus here in the forum may set things streight in providing us with a "chain of command" diagram ?

[v_o_r_t_e_x]

Unfortunaltey, I have no more information regarding this.
But it would be really interesting to know how it really works in meGUI.

BTW: Does anyone know a tool that tells me the sync "time"?
If I have a VOB or M2V and a AC3 stream, how can I find out
the correct sync?

[Doom9]

What an old thread you managed to dig up here.
Has nobody ever looked at the audio configuration dialog after loading an audio source? Did nobody notice that if the filename contains a delay, that the delay checkbox automatically gets checked and the value field has the value from the filename?
This is done independently for every audio track you load.

And have you ever seen an audio software that corrects delays but changes the output filename? The software I have used before all just change the extension to the desired one - none adjusts the filename (e.g. by removing any delay string) even if delay correction is being done.

And by demuxing, you lose the greatest source of information about delays. Some AC3 encoders might add some delay information, but your best shot is the VOB file and after all MeGUI uses DGIndex which provides that information upon demuxing free of charge and it makes very little sense to use something else and make your live harder.

[v_o_r_t_e_x]

It's a little bit off topic. But I'm using DGIndex and have the problem, that it reports 0ms delay, but once everything has ben processed by meGUI, the output file (an MP4) has a delay of about 1500ms. I have a VOB file, but how to get the real delay out of it?

You find the details here: http://forum.doom9.org/showthread.php?t=128369

[buzzqw]

try this (suggestion by Neuron2):

open wth dgindex your vobs, just click 1 or 2 time or > arrow , then save the project, and use this d2v for feeding megui

why ?
on bad rip, or heavy protected dvd, there are some wrong gop at start, and these wrong gop have incorrect timecode and so dgindex reported wrong delay, BUT trimming some gop usually fix this incorrect delay

BHH

[Jerethi]

How exactly would one correct a video-audio sync problem if the filename for the audio indicates that there is NO delay? Any thoughts on what might cause this?

[v_o_r_t_e_x]

The solution for my file was, to load it into MPC (video and audio stream separatly) and find out the sync delay manually (you can enter a delay in MPC and then play the files.
After that I muxed it using meGUI and there I had to enter the sync delay manually. In MPC the delay was about 1500ms, and in meGUI I had to enter -1500ms.

[v_o_r_t_e_x]

Has nobody ever looked at the audio configuration dialog after loading an audio source? Did nobody notice that if the filename contains a delay, that the delay checkbox automatically gets checked and the value field has the value from the filename?
This is done independently for every audio track you load.


I just tested this with meGUI 0.2.5.1007.
And it did NOT set the delay values automatically!
I had to do it manually.

[Shandra]

Haven't we mentioned somewhere on page 1 (at least I for one of my "tests" (Edit: Post #11)) that even if the box is not checked and no value is entered manually the encode actually does incorporate the delay of the filename... ticking the box and entering a value simply overrides any detected offset within the filename, but it ain't needed if the filename has a delay set.

Just create a simple short wav, set various delays for the filename and look at the result - the delay will be added or cut from the original playtime.

[v_o_r_t_e_x]

Seems my brain needs some holidays... thanks Shandra :)

Is there a way to see if meGUI applied the delay? I suppose
I should see it in the XML files used in the queue.

[foxyshadis]

You should find the information in the logs, as well. I can't remember, since I always correct it in the avisynth.