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[post:500#4880]
Stretch

01/13/2011 11:31 AM

Reviews: 1918
Posts: 1313

Would you advise me to download VirtualDubMod? Is it a program that must be used instead of VirtualDub when converting from MKV to AVI, or can part of the job (fixing timing problems) be done there and the rest be done with VirtualDub?

[post:500#4881]
Devil Doll

01/14/2011 01:21 PM

Reviews: 365
Posts: 1574

Download VirtualDubMod from Sourceforge. It's a ZIP archive so it has to be extracted (with WinRAR in your case) to a directory of your choice, just like you did with VirtualDub.

Both of the above ideas are feasible. VirtualDubMod can do everything that VirtualDub can and some more. If it weren't out of maintenance since 2006 I would have suggested using it instead of VirtualDub in the first place. I suggest you just try doing the whole conversion with VirtualDubMod once (the menu names are slightly different, most notably for the batch queue) and then decide which one you like better.

You can also open the conversion result from VirtualDub (i. e. the AVI file with the out-of-sync audio stream) with VirtualDubMod, select "Video / Direct Stream Copy" (in order to use the already existing video stream without modification), and just try setting a different offset with "Streams" / "Stream List" / right mouseclick on the audio stream / "Interleaving" (this is what VirtualDubMod can do but VirtualDub can't). In this dialog, set the value for "Delay Audio Track by" to an estimated appropriate value, and then "File" / "Save AVI" (which should take about 5-10 seconds as the file is basically just copied). Post-processing the compression result for the audio fine-tuning is much faster than repeating the whole video compression.

Leave VirtualDubMod activated so that you can just set different delay values until the result suits you. I usually guess the required offset, and then vary it by an amount that I cut into half for each subsequent attempt, such as: Audio plays too early; try +200 (now Audio plays too late), +100 (Audio plays a bit too early), +150 (Audio plays a little bit too late), +125 (okay) or something like this; usually 3-5 attempts will do, an offset variation below ca. 20 ms will probably make no more audible difference.

There might be a better way with less effort if it were possible to read the offset from the original container (i. e. the MKV file the conversion started with). But I don't have a file at hand that I know to have a non-zero offset so I can't check whether MediaInfo would show you the exact value of this offset.

[post:500#4882]
Devil Doll

01/14/2011 01:21 PM

Reviews: 365
Posts: 1574

This is the second time I unintentionally added a posting twice. Could this be a side effect of the "fixed" posting feature?

Edited on 01/14/2011 01:27 PM.

[post:500#4883]
Stretch

01/15/2011 11:17 AM

Reviews: 1918
Posts: 1313

I 'extracted' VirtualDubMod.exe and .vdi, opened the folder which had automatically been created for them, but when I try to open .exe itself I get this:

'This application has failed to start because corona.dll was not found. Re-installing the application may fix this problem'.

Corona.dll? What's that?

Back in the extraction step I got a warning that WinRaR was just an 'evaluation copy', but it didn't say anything about it having possibly expired.

[post:500#4885]
Devil Doll

01/15/2011 07:04 PM

Reviews: 365
Posts: 1574

My archived version of VirtualDubMod 1.5.10.2 is a file of 1.663.748 bytes (CRC32 = "933848f0"). It contains 28 files, amongst these a corona.dll of 125.440 bytes.

I surfed around on the SourceForge page, and the subdirectory http://sourceforge.net/projects/virtualdubmod/files/VirtualDubMod/VirtualDubMod%201.5.10.2/ has a larger ZIP file (1.7 MB, with "all inclusive" in the filename) that has almost the same content as my archived version (the difference being just one redundant "read me" file). Sorry to have pointed you to an incomplete file (that apparently only holds the "core" of VirtualDubMod), I didn't expect that either.

About WinRAR being ↗Nagware I posted in the previous thread already.

[post:500#4887]
Stretch

01/16/2011 10:47 AM

Reviews: 1918
Posts: 1313

Oh yeah, the ones which continually warn that they will expire, but actually just want me to buy a fancy version instead of using a free, simple version. I remember. I will uninstall the incomplete VirtualDubMod and start over.

[post:500#4888]
Devil Doll

01/17/2011 12:34 AM

Reviews: 365
Posts: 1574

You can just extract the archive into the same directory, it's a superset of these two files.

[post:500#4889]
Stretch

01/17/2011 03:33 PM

Reviews: 1918
Posts: 1313

At SourceForge I get 'Your VirtualDubMod download will begin shortly...' but that's as far as it goes--somehow it gets hung up at this point. It remains like that literally for hours without changing. I tried a 'direct link' and another 'mirror', but they don't make any difference.

[post:500#4890]
Devil Doll

01/17/2011 11:07 PM

Reviews: 365
Posts: 1574

For me the download begins immediately.

VirtualDubMod is available on many sites in the web. Do a search for "VirtualDubMod download" and you'll get 8,66 million hits, one of them being http://www.free-codecs.com/virtualdubmod_download.htm. The version I've been using for years (and is listed in Wikipedia) is 1.5.10.2 so I suggest you use this one; the version 1.5.10.3 from 2009 apparently comes from http://www.virtualdub-fr.org/ of which I have no idea who these people are.

[post:500#4896]
Stretch

01/26/2011 05:32 PM

Reviews: 1918
Posts: 1313

Sorry it took me so long (I had a dental root canal performed Monday), but I have finally downloaded and extracted VirtualDubMod 1.5.10.2 (even though 1.5.10.3 was also available) from the website you suggested above. A folder much like that of VirtualDub was created, which is encouraging. It was easy to find the right commands which you had listed in your instructions. But I didn't have much luck with my first attempt. No matter what value I set there didn't seem to be any recognizable difference to the audio/video timing. I wonder if the problem might have been that the timing of this episode seemed normal at first but went out of sync at some point afterwards. I was going to report that I couldn't make this system work, but I tried a different episode and on the very first try the timing seemed to become perfect. So, I have had mixed results so far.

[post:500#4897]
Devil Doll

01/26/2011 06:43 PM

Reviews: 365
Posts: 1574

Can you name a file where you have problems? Looking at this file's video attributes might give us a clue what's going on there (variable video frame rate?). If the file is in sync at first but out of sync later this looks like the speed between video and audio is different, and if that wasn't the case for the original file then the video frame rate might have changed during the video recoding process - that's where I would look for the cause of the issue.

[post:500#4898]
Stretch

01/27/2011 01:30 PM

Reviews: 1918
Posts: 1313

Well, I thought I had fixed an episode of Level E, but today all of the copies I have are similarly out of sync and I can't re-fix them. A certain line is spoken at 9:16 and the character's lips don't move until 9:20. But no matter how many times I run the flawed episode through VirtualDubMod (at +400), the problem remains unchanged--a four second mismatch of audio and video. I wonder if I'm doing something wrong which causes the +400 value to be dropped and the episode to basically be recopied in an identical form. One difference between your instructions and what I do is that there is no exact match to "Save AVI" (F7) within File, instead I use "Save As" which uses AVI by default; but I doubt if that would matter. This must have been either the CrunchySubs or HorribleSubs version of Episode one. The fansubs I get from those two outfits wind up out of sync after being run through VirtualDub so often that I have made a point of avoiding them recently. One other thing: what I often run into in episodes which start off OK but become out of sync later doesn't seem to be a steady, gradual loss of synchronization, rather it runs perfectly well for a good while, perhaps even to the station break, then afterwards the sync is immediately very much messed up. It makes me wonder if the fansubbers have somehow broken the episode up into pieces while working on it, and my software can't deal with whatever changes they have made...if that makes any sense to you.

Edited on 01/27/2011 01:43 PM.

[post:500#4900]
Devil Doll

01/28/2011 12:04 AM

Reviews: 365
Posts: 1574

The offset unit is miliseconds, i. e. a thousandth of a second, so a 4 seconds delay would be +4000, not +400. Its obvious that you can't see that much of a difference when the track is still 3600 ms off.

But both the HorribleSubs and CrunchySubs releases for Level E are MKV containers using ↗Variable frame rate for the H.264 video streams; your idea of the episode being broken up in parts is a bull's eye. (And once again, these two rippers left you with a format incompatible to what most fansubbers release...)
Now why would someone use such a strange format? The "showy" OP/ED sections of anime are sometimes produced with a higher video frame rate than the rest of the episode (in order to make the excessive movement in these sections appear more fluid), the main parts of the episode with less movement don't require the same amount of video frames; 29,97fps for OP/ED and 23,976fps for the main episode part are quite common values. So the original videos would then in fact contain several parts with different frame rates in these cases; simply playing these videos with one constant frame rate (which is what our simplistic AviSynth script is doing during the conversion process) would change the video speed and thus get the video out of sync with the audio, just what you are observing. The MKV container format supports variable frame rates, i. e. one MKV container may contain several video parts with different frame rates; AVI only supports one frame rate per file. Houston, we have a problem.

So in order to get such a video into an AVI container the fansubbers would have to specify one common frame rate for all parts and convert some of the parts to this frame rate, resulting in either quality loss of the OP/ED (if you ever observed jerky movement of scrolling credits during the ED section of an anime movie you now know the reason for it) or unnecessarily inflating the main part of the episode by "useless" additional frames (plus making the main part's movement jerky as well, only that it won't be as noticeable if there isn't that much movement).
An alternative would be to recode the whole video stream to a common multiple of the frame rate (for 23,976fps and 29,97fps this would be 119,88fps), i. e. effectively using 4-5 times as many frames as the original video; there are in fact anime files out there that went this way (mostly raws, i. e. unsubbed anime, in AVI or even WMV containers) but the success of the MKV container made this makeshift obsolete many years ago. Besides, your stand-alone player probably won't play videos with 119,88 frames per second.

Given all of the above, you might have to switch to a fixed frame rate release. The WhyNot group does an edit of the Crunchyroll subs in a MKV container with 23,976 frames per second so this release should work fine for our conversion procedure, and they have released episode 3 already (RedFaction also does a 23,976fps release but apparently dropped the series after the first episode).
Check the MediaInfo report of these files; does it show "VFR" for the frame rate of the video? This is how you might identify these files before starting the conversion process.

Just as an aside: You could do the conversion of these videos yourself but it's tricky. Within the AviSynth script you are currently reading the whole video file at once; you could determine the frame numbers for the end of the OP resp. the beginning of the ED section, then read only subranges of frames, i. e. create separate streams for OP, ED and main video part, convert each of these to the common target frame rate (by decimating the frames from OP/ED), and finally concatenate all parts to one "master stream" for the subbing process (AviSynth is a powerful script language after all). That's probably what the WhyNot guys are doing (plus some editing of the CrunchyRoll subtitles).

Edited on 01/28/2011 03:56 AM.

[post:500#4902]
Stretch

01/28/2011 09:56 AM

Reviews: 1918
Posts: 1313

OK, this makes sense. Actually I have already found non-Crunchy or Horrible sub versions of each of the series which I'm currently watching (I watched the RedFaction sub of episode one of Level E, and have been getting the episodes from Baka subs since then). I just hope someone who isn't using variable frame rate keeps producing fansubs until the series ends. If all else fails and a show which I really, really want to watch is only available with VFR, perhaps I will try to convert it myself--or maybe I'll give it a try just because I'm curious. Thanks again for your help!

Edited on 01/28/2011 09:58 AM.

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