Muxing AVI and AC3 with AVIMux...

[BluDChyLD]

Thought i'd give this a go instead of nandub to avoid potential playback problems...

I demuxed the ac3 from the vobs using dvd2avi and it has a -80 interleave value in the filename. In nandub you have to adjust the interleave according to this value, however in doom9's guide to avimux it says to always leave it at default (75). Why is this?

[DJ Bobo]

I never experienced problems with files made in nandub.

DVD2AVI doesn't give you the interleaving value, but THE DELAY.

Interleaving & Preload must be set to 96ms, no matter what kind of ac3 you have.

[BluDChyLD]

oops my mistake! Tried it and everything's ok, it's strange how you don't have to specify the delay value like you do it nandub and it still plays in sync...

[iago]

Well, maybe I am just another lucky guy, but just like DJ Bobo, so far I haven't got any problems either, with muxing AC3 and AVI using 96ms for both "Interleaving" and "Preload" values in Nandub.

best regards,
iago

[Zhnujm]

you have to set the interleave to 96ms because of nandubs buggy ac3 mixing. in avimux you can use almost every value.

and i think you have to use the delay in avimux also. (maybe you have to fix the delay before muxing)
the -80ms delay is maybe to small to be visible.

[BluDChyLD]

I normally use ogg sound, but if I keep the ac3 I just let gknot do the muxing... No problems so far, but I thought i'd start using this tool to be on the safe side. What kind of trouble can ac3 muxing cause, does it only happen when you use a SPDIF output?

[downloada]

hi,

you have to set the delay in avimux, too, but it's a little hidden. just right click on the audio-stream you want to set the delay for and select "set delay". then just input the value in the filename and everything's fine...

cu

[valnar]

Newbie clarification:

So if I want to mux an AC3 file into a newly created DivX video only file, I should, for best compatibility with S/PDIF:

* Not have Gordian Knot do any audio muxing at all
* Take the resulting AVI (DivX 5.02) file and
* mux it to the AC3 file in AVIMux?

Yes??

Thanks,
Robert

[BluDChyLD]

yep, that's the best way :)

Quick note - 1.11 has just been released :cool:

[MaTTeR]

Originally posted by DJ Bobo
I never experienced problems with files made in nandub.

Interleaving & Preload must be set to 96ms, no matter what kind of ac3 you have. Is it safe for me to assume you don't use SPDIF out then? If you do, surely you have seen jerky playback and _excessive_ CD access. Secondly, using 96ms interleave with NanDub's buggy AC3 muxing isn't the silver bullet either with respect to the rest of us who use SPDIF out. Acaila doesn't use SPDIF and he once mentioned he has to use different NanDub interleave values depending on the AC3 bitrate for the smoothest playback. I keep saying this but I really have to get the AC3 FAQ updated with all this new information, lack of time though.

Yes indeed, in general it appears the interleave values aren't so critical unless your going to SPDIF. If you use AVImux then you can use alexnoe's defaults of 500/75 and they work perfect, safest tool to use in regards to AC3 muxing. This tool was an absolute God send IMHO:D

[valnar]

Originally posted by MaTTeR
Yes indeed, in general it appears the interleave values aren't so critical unless your going to SPDIF. If you use AVImux then you can use alexnoe's defaults of 500/75 and they work perfect, safest tool to use in regards to AC3 muxing. This tool was an absolute God send IMHO:D

Sometimes procrastinating is good! I waited this long before doing anything DiVX and now I have all these great tools to do it right! :D
Until a new MM container standard emerges from the fighting, I'll keep the AC3 intact and merge it with a DiVX 5.02 AVI for now.

Of course, I waited too long before jumping on the MP3 bandwagon too... and I only had a couple months to get all the MP3's I could eat with Napster. :(

-Robert

[Ripe73]

Hi all!!!

I start using Avimux and there is a "maximum file size" option...do

you use it for splitting or you just mux and do the splitting with Nandub??...Avimux split correct??

Thanks for any inputs..

[tiki4]

@Ripe73:

Yep, that's right. The 'max file size' is exactly after which AviMux splits and creates a new AVI. It's naming scheme is something like 'name (1).avi', 'name (2).avi' etc.
Take a look at the new AC3 guide on the main doom9 site. You should use AviMux for DivX/AC3 instead of NanDub because NanDub sometimes cutes AC3 frames in the middle when cutting your video. So I'd say AviMux is the safe way to go!

Regards,

tiki4

[alexnoe]

One slight note on the guide: If you uncheck the max file size option, the current version will refuse to work if you try to safe to an FAT32 drive...but I'll change that so that 4000 MB is automatically set when writing to FAt32 ;)

[tiki4]

Never read the guide, never tried to save to FAT32, figured out the rest by myself, but a ReadMe.txt about basic usage would be quite nice. The thing with the audio delay is maybe not too easy to find.

Cheers,

tiki4

[alexnoe]

The link to my homepage is among the doom9 links...there, you also find pre-releases or quick bux fixes

[tiki4]

Thanks, I'll have a look.

tiki4

[Micro]

Just one question:
Does avimux always cutting at keyframe ?

[alexnoe]

It cuts at keyframes only.

One exception: If you manually enter a frame at which you want cut, and this is not a keyframe, then it will display a warning and asks if you really want to cut at a deltaframe.

[valnar]

One more question. Is Gordian Knot or Nandub faulty in any other muxing capacity, or just AC3? When doing DivX, is it best to use AVIMux for MP3 audio as well, or can GKnot handle that fine?

Yes, I know both "work", but I'm always after the better option.

Thanks,
Robert

[alexnoe]

If you use MP3 audio with 44.1 kHz: Use NanDub. AVI-Mux GUI miscalculates the frame lengths and cannot split correctly. The 2nd file and eveything after it would be out of sync if you split. I still don't get what's wrong :mad:

If you have MP3 audio with 48 kHz: Use AVI-Mux GUI. The abovementioned bug is not present, so you will not have the heavy access of the source discs while replay.

[valnar]

Thanks Alex. Do you have a prefered utility (since there are so many) to convert an AC3 to a CBR MP3?

Robert

[alexnoe]

No, I haven't made a new MP3 file for quite some time (DVD-Rs have enough space to store AC3 *g*), so I can't help you with the conversion. The FAQs and guides here on Doom9 should suffice, though.

[Atlantis]

Hi! First thanks for this wonderful software. I just discovered AVIMux. I have a problem with it and don’t know if it’s a bug or my lack of knowledge. I have a video file and 2 audio files which I want to mux into 3 CDs. I cannot join the two ac3 files before because the second audio is out of sync when I mux the video and the two ac3s joined! I want to import the 2 ac3 files into AVIMux and change the delay of the second ac3 there.

The problem is that the second ac3 file doesn’t seem to be muxed into the avi files and there is silence. Also starting from where the second ac3 file is supposed to be, the avi doesn’t split anymore. I get one 690 MB file and one 1500 MB file! I should add that the second ac3 file comes from a second DVD and maybe the timestamp starts from 0 for that too. Is that a problem? What should I do?

[Atlantis]

Some additional thoughts. When there are two audio files and the second file has a positive delay what happens? I mean what will AviMux add at that point? Is it going to encode silence in the specific audio algorithms (like wav/mp3/ac3) or is there practically nothing at that point as the audio stream? I was always wondering that.

[alexnoe]

AVI-Mux GUI will onyl mux *selected* audio streams. If none is selected, it uses all.

You select an audio stream the same way as in any multi-select-listbox: pressing ctrl+clicking onto it.

About your 690+1500-problem: this should indeed not occur. It has been reported a few times before, but I can't reproduce it.

[Atlantis]

I also tried it by MP3 and it gives error at the end of audio1. I think it’s maybe because the 2 audios combined have not exactly the same length as the 1 video length. They never are. They always have fewer frames than video when you encode one big vob.

So concatenating two audios (coming from 2 vobs from 2 different locations) will cause problem. I think you might be able to reproduce it if you take two vobs from 2 different locations and be sure to go right at the end of vob1 vts because if you cut it before, the audio is always going to have the same length as the video.

What I finally did was that I cut my avi into 2 and used avisynth to get a perfect audio sync like this:

video1 = OpenDMLSource("Split_1.avi")
audio1 = WAVSource("Audio_1.wav")
Res1 = AudioDub(video1, audio1)

video2 = OpenDMLSource("Split_2.avi")
audio2 = WAVSource("Audio_2.wav")
Res2 = AudioDub(video2, audio2)

Res1 ++ Res2

I open this file in VirtualDub and saved the wav and encoded that wav. Later I opened the one video and one audio file in avi_mux.

[marcobdivax]

@alexnoe

Just before discovering your tool, I was trying to find a preload/interleave criteria using virtualdubmod to mux avi&ac3.
In the past I was using suggestions from this forum with preload/interleave according to the ac3 bitrate (160/160ms for 384kbps and 128/128ms for 448), honestly with success using different pcs (with spdif, also).
BUT, days ago I buyed a compaq presario where I tried to play the same avis (from cd) with choppy playback during scenes with pan&scans; playing avis from internal hd seems to lower the problem, but not completely.
So I've isolated the scene (1 for 384 and 1 for 448) and then remuxed it (virtualdubmod) with differents preload (different interleave seems to have always a negative effect), discovering that a "ten" factor (and multiples, respect to the interleave value) solve the problem (on my notebook, and no collateral effects on the home pc); but, to be sure, I've shipped a cd with the avis (with problem and not) to 15 friends to test it, with complete positive results (unfortunately, only 2 of them have spdif connection, so this must be better tested).
Then I've seen your tool and I've tested it ('cause I was tired to consider a problem tune interleave/preload), but I've a strange behavior: (same scenario, same cd) playing is smooth but with 1/2 sec stops (usually one, in the last 10 secs, but the scene is 45 secs...) on different positions (I mean, if I play continuosly/randomly the avi), while the vdubmod avi has a correct visualization.
I've used the standard (default) avimux settings.
Please note that I used vdubmod to cut the scene & extract separately video and audio (and then muxed with avimux), so maybe there's a problem in the first/last ac3 frame: do you think this could be the problem? Can I use a larger avi to test?
Thanks for your patience, (I'm sorry for the english).
Marco

[alexnoe]

@marco: Some CD drives show the annoying behaviour of spinning down after a few seconds without access, and then don't send data before having spun up again.
In this case, set a low speed with a tool such as Nero CD Speed, and try an interleave of 50 in AVI-Mux GUI.

One user has also reported a buffer problem with a strange Sigma card: 75 frames of detailed video caused a buffer overflow and jerky replay...in his case, lowering the interleave to 50 also helped.
Maybe I should set 50 as standard in the next release.

Testing with larger AVIs is also a good idea.

I've got an idea: I should add rec list size, not based on frame number, but based on data size...

[marcobdivax]

Thanks a lot, Alex.
I was in doubt, also, about spin down and I set (nero) 10 minutes of before spin down (and tried with 24x/16x/10x speed to check for possible hardware problems).
This evening I'll try with interleave 50, hope to send you a positive feedback.
BTW, could you tell me where to find details on avimux (checkbox values, meaning and so on)? I've seen notes about a guide on this site, but apart from a screen, nothing other...

Thanks again
Marco

[alexnoe]

http://www-user.tu-chemnitz.de/~noe/Video-Zeug/AVIMux%20GUI/

Available in German and English at the moment.

[Wilbert]

I thought you uploaded a new version?

[alexnoe]

Pre-release!
=> http://www-user.tu-chemnitz.de/~noe/Video-Zeug/AVIMux%20GUI/#download

[Wilbert]

Thanks, I will try it!

[alexnoe]

I've just uploaded the modification which allows to make rec lists of almost constant size, instead of constant frames.

Note that you enter the desired size in kBytes.

I've tried 250 kByte, and now I can replay the test file (Predator, Quant. max = 3, 3 MP3 streams) with a CD speed of 4x! This pattern seems to be even better than the frame-based one.

[MaTTeR]

alexnoe,

Perhaps its just my HTPC system but DTS/AVI files seem to have more frequent CD I/O access than an AC3/AVI file. Have you noticed this at all? I've just tried using the defaults of 500/75 up until now. Would using a constant size with your new build might help? I'll try and find some time later this week to test it more. TIA

[alexnoe]

No I haven't, but I have not even tried to replay a DTS AVI from CD...
The constant size will actually increase the access a bit.

The problem with constant frame numbers is: If there is a very detailed scene, you may have a single block of 2 or 3 MBs. But if the drive is set to 4x, it takes veeeeery long to load 2 MBs (over 3 seconds) => movie will hang, because the block to replay is not yet loaded.

With the constand block size, you can ensure that on the one hand, the blocks to load in one piece are not too large, but that on the other hand seeking is still not necessary.

Don't ask why I did not come up with this idea earlier. I don't know it...

[marcobdivax]

@alexnoe
I've tried to mux avis using interleave 50ms and 50-250KB but I've again the same problem playing from cd on my notebook (compaq presario 920ea, 24x cdrom with 10minutes spin-up via nero drive speed): compared to the same avis muxed via virtualdubmod (preload 1600 interleave 160 for 384Kbps and 1280/128 per 448), "your" one seems smoother but with freezed frame (about 1/2 sec.) in constant position (I mean same position replaying more the once the avi) using different players (note that the problem seems absent playing the avi from gd); same cd, vdubmod avis: they are very similar to the hd ones, a little (little,little,little) choppy but no freezed frames.

Any suggestion?

p.s. I've tried avimux with the same interleave/preload as vdubmod, obtaining (unfortunately) much more freezed frames

thanks
marco

[alexnoe]

That's really strange...did you try switching rec lists off, or a preload of 0?

[marcobdivax]

Thanks, Alex, I'll try this evening.

marco

[marcobdivax]

Hi, alex.
I've tried 1) interleave 50ms, preload 0, reclist
2) interleave 50ms, preload 0, no reclist
3) interleave 50,s, preload 500, no reclist

The results are the same, and in one case video freeze at precise intervals (about every 2 secs).
Again, the playing is smoother than vdubmod avi (but it has no freeze).

Hope you have any suggestion...

Thanks
Marco

[alexnoe]

At the moment, I don't :(

[marcobdivax]

@alex
I've forgotten to say that the behaviour is the same on a friend's notebook (hp evo, with combo cd-dvd-cd-rw), with different graphic card/audio card.
Of course, this doesn't state that there are no hardware problems, but...
Hope you can analyze the fact that one combination reclist/preload has those freezed frames with constant delay (maybe linked to something).

:D as jasmin did on another 3d, I'm sure you'll find the problem.

marco

[marcobdivax]

Alex, after a big war I've found that the problem was due to an incorrect setting of the ide controller (on XP): it seems that (notebook) if dma is disabled (PIO mode) the freeze is a constant (but only with avi produced by avimux); after reinstalling XP on the notebooks with the problem ('cause it was impossible to re-enable dma without it), avimux cd avis are smooth regardless the parameters (reclist/preload and so on) I choose.

Now 2 (simple) questions: preload/interleave must be linked to the ac3 frame size (multiple of 32) or 50/500 value is the "final" value? And what about size in KB, have you any suggestion in using it?

Thanks Alex, please excuse me if you waste time thinking about the problem.

marco

[alexnoe]

Ah...so it's no bug of mine :D

In AVI-Mux GUI, interleave/preload is not required to be linked to anything.

I suggest an interleave of 250 kB. Preload does appearently not really affect playback, so 500 should be fine.

[fANMIR]

Hello...

I have been using avimux with great results for some time. But recently I tried to force spliting avi file at exact keyframe. The first file is ok but second has a small delay between audio and video (very small but noticeable). When spliting is automated it works ok.

I was muxing video with 384kbit/s AC3 via avimux 1.11. rec-lists, open-dml were active. Delay for audio was -80ms. The rest of the settings were default. I am wondering is it a common problem, but I didn't find anything similar at the forum.

[alexnoe]

It is not "common", but it has already occured several times. I'm trying to find the reason for it, but as long as I can't intentionally cause this effect, this is not going to be easy :angry:

Note that 1.12 is already out

[fANMIR]

I was specyfing exact spliting point because I had problems with cutting the file into two parts. When I set 698MB as spliting point I got 704 Mb of first file. When I specified something below 698MB I got 3 files (part 3 has size about 1.6MB). The sync was ok in all these situation. Then I tried to specify cutting point by keyframe - and yes I got two files <700MB but the last one was out of sync. I am not a programmer but it looks like avimux didn't see some keyframes as possible cutting points - It was possible to create 2 files by splitting on specified keyframe (with sync problems) or to create first file oversized or 3 files with the third very small when I specified creating volumes of specific size...

[alexnoe]

I'll see if I find the reason for that problem.

Version 1.12 offers the possibility to specify the maximum number of output files.

[alexnoe]

Got it (i think). Was probably the most silly bug ever which I had!