VirtualDubMod, BeSweet and Bitrate Questions

[Qyot27]

Should I now reduce the "Max consecutive BVOP's" to 1? I did my tests with 2 and it was fine, but if I don't reduce it to 1, what will happen exactly? Compatibility/sync issues for people who don't have XviD?

I would say yes, reduce it to 1, but be aware that this will hurt your compressibility somewhat.

However, that page is a few years old by now, and the newer versions of the DivX decoder may not have this problem anymore. I would suggest installing a copy of the DivX codec (version 5 or later), encoding the video with FourCC DX50 (DivX should then be the first choice to decode this instead of XviD, assuming you don't have ffdshow or have its DX50 support disabled), and playing it back to see if there are any problems.

I use ffdshow (if that's not selected it defaults back to DivX 5.2 and XviD 1.1.3), and I certainly don't see a sync problem even when 2 are selected, regardless of which one is doing the decoding or whether Packed Bitstream is selected also or not. As this was the source of the problem then a sure-fire way to bypass the issue, as I'd suggested testing earlier, is using MP4 or MKV and allowing the video stream to be Native MPEG-4 rather than specially hacked to fit inside of AVI. The problems experienced here deal explicitly with the issue of AVI not supporting B-frames and thus to have them, they need to be hacked in.

The hacks simply come with a price (that is, potential audio desync), but because of how ingrained DivX/XviD-encoded AVIs are, putting them into a container that properly supports the B-frames, even if it is the one defined in the MPEG-4 standard, will make for people complaining at you because they can't play it back or have something against other containers (probably based on bad experiences or a preconceived notion that MP4 or MKV equals H.264 rather than MPEG-4 Visual - DivX or XviD - and therefore processor choke because on average, H.264 requires more powerful hardware).

[Kero777]

Unfortunately, I was wrong about what I posted yesterday. I was dumb and previewed a part that didn't really have as much "timing" to it as other. It's still... off...

I would say yes, reduce it to 1, but be aware that this will hurt your compressibility somewhat.

I may still stick with this method, but I hope it doesn't hurt it too much because I have trouble with some videos' compression.

However, that page is a few years old by now, and the newer versions of the DivX decoder may not have this problem anymore. I would suggest installing a copy of the DivX codec (version 5 or later), encoding the video with FourCC DX50 (DivX should then be the first choice to decode this instead of XviD, assuming you don't have ffdshow or have its DX50 support disabled), and playing it back to see if there are any problems.

Ah, yes. This is what I have been doing: Been choosing XviD and then DX50 for the FourCC to make it more compatible. It's just not many people seem to have this problem at all besides my friend and I and a couple of other people on this website.

I use ffdshow (if that's not selected it defaults back to DivX 5.2 and XviD 1.1.3), and I certainly don't see a sync problem even when 2 are selected, regardless of which one is doing the decoding or whether Packed Bitstream is selected also or not.

For the FourCC? I chose not to install ffdshow with the AMVapp because I was told it conflicted with some other codecs. I had a lot of trouble with codecs on my old computer.

As this was the source of the problem then a sure-fire way to bypass the issue, as I'd suggested testing earlier, is using MP4 or MKV and allowing the video stream to be Native MPEG-4 rather than specially hacked to fit inside of AVI. The problems experienced here deal explicitly with the issue of AVI not supporting B-frames and thus to have them, they need to be hacked in.

I tried using MKV with the compression of MP4 (did I understand you correctly? Not actually using AVI at all?) and the quality was horrid for some reason. It does seem to play smooth though. For some reason I do not have the other options. Maybe missing codecs?

The hacks simply come with a price (that is, potential audio desync), but because of how ingrained DivX/XviD-encoded AVIs are, putting them into a container that properly supports the B-frames, even if it is the one defined in the MPEG-4 standard, will make for people complaining at you because they can't play it back or have something against other containers (probably based on bad experiences or a preconceived notion that MP4 or MKV equals H.264 rather than MPEG-4 Visual - DivX or XviD - and therefore processor choke because on average, H.264 requires more powerful hardware).

That stinks... so it's either not-as-good sync or compatibility issues and people won't be able to watch it. I'm really stuck. I still feel like I am doing something wrong with the DivX compatible XviD file conversion described in the guides. I'm going to go re-read the last sections again. Is there a guide for the MKV conversion? Maybe I am doing that wrong too. I hate to keep bothering everyone with so many questions. Thanks so much for your time. It's appreciated tons *Feels very stupid right now*

[Qyot27]

For the FourCC? I chose not to install ffdshow with the AMVapp because I was told it conflicted with some other codecs. I had a lot of trouble with codecs on my old computer.

For the FourCC it doesn't seem to matter if it's XVID or DX50. I use DX50 for my own encodes (well, the ones that I encode using XviD, anyway). Old, decrepit versions of ffdshow are known to pop up in codec packs and conflict with the rest of the codecs the same packs install, but I certainly haven't experienced problems arising from using ffdshow. In it's configuration you can tell it which ones to handle, and if it seems to cause a problem with a particular format, you can just tell it not to decode that one.

The version of ffdshow I use is from the ffdshow-tryouts project, located here:
http://sourceforge.net/project/showfile ... _id=173941

I've stopped keeping track of which version is in the AMVapp, since the page there is guaranteed to have the very latest builds (which on average, occur at least once a week). I'm sure the new AMVapp beta uses one of the tryouts builds, but I don't know which one.

I tried using MKV with the compression of MP4 (did I understand you correctly? Not actually using AVI at all?) and the quality was horrid for some reason. It does seem to play smooth though. For some reason I do not have the other options. Maybe missing codecs?

I meant, use the MP4 container or the MKV container. DivX and XviD are implementations of MPEG-4 Part 2, specifically Advanced Simple Profile (ASP). The MP4 container is another part of the MPEG-4 standard. H.264 (which is causing the MP4 container to gain popularity around here, but it's also used for AAC audio like the purchases from the iTunes store) is MPEG-4 Part 10. Both ASP and H.264 can be stored inside MP4. Think of it like MPEG-1 or MPEG-2 and their respective Program or Transport streams.

Is there a guide for the MKV conversion? Maybe I am doing that wrong too.

For MKV, all you *need* to do is take your already-encoded XviD AVI file, load up MKVMerge GUI, click the add button on the main screen, select your video and audio (or just the video if it has the audio already attached), go to the Muxing menu, click 'Add command line options', select --engage native_mpeg4 from the drop-down menu, click Add, then go back to the main screen and mux as usual.

The part for MP4 is mostly setting up the program.

For MP4, you'll need YAMB. I use 1.6.0, which you can find at that link (which is the developer's personal site; newer versions can be found on the official website, but these instructions are for the older version - if you want to use the newer ones then this will probably act as a good guideline, at any rate). If it tells you it needs libmmd.dll, it's also at that link where 1.6.0 is. Go to the Options tab, and select Enable Import Settings (you might also have to tell YAMB where MP4Box is, use the arrow next to General on the same Settings tab and choose MP4Box - you'll see the place where you can tell it where the executable is, which should be in YAMB's Program Files folder - typically C:\Program Files\YAMB\ or wherever it was that you chose to install the program to during setup).

Go back to the Mux tab, click Add and select your already-encoded XviD AVI file. The Import Settings dialog will show up. Make sure that Remove N-VOPs and Import only Video Track is selected. It can automatically detect the framerate from AVI files so you more than likely won't need to use the Force framerate option. Click OK and it'll go back to the main screen. Now to add your audio, click Add again and choose your audio, the dialog will pop up again; you won't even be able to access the N-VOPs or framerate options so don't worry about them, make sure the Import only Audio Track is selected and press OK. Now just click Mux and it'll do it's thing. That's it.

[Kero777]

I apologize for taking ages to reply! I've been caught up in some things.

For the FourCC it doesn't seem to matter if it's XVID or DX50. I use DX50 for my own encodes (well, the ones that I encode using XviD, anyway). Old, decrepit versions of ffdshow are known to pop up in codec packs and conflict with the rest of the codecs the same packs install, but I certainly haven't experienced problems arising from using ffdshow. In it's configuration you can tell it which ones to handle, and if it seems to cause a problem with a particular format, you can just tell it not to decode that one.

The version of ffdshow I use is from the ffdshow-tryouts project, located here:
http://sourceforge.net/project/showfile ... _id=173941

Yes, I installed a codec pack before and even after uninstalling I had the same problems. Thank you for the link. I might try that.

For MP4, you'll need YAMB. I use 1.6.0, which you can find at that link (which is the developer's personal site; newer versions can be found on the official website, but these instructions are for the older version - if you want to use the newer ones then this will probably act as a good guideline, at any rate). If it tells you it needs libmmd.dll, it's also at that link where 1.6.0 is. Go to the Options tab, and select Enable Import Settings (you might also have to tell YAMB where MP4Box is, use the arrow next to General on the same Settings tab and choose MP4Box - you'll see the place where you can tell it where the executable is, which should be in YAMB's Program Files folder - typically C:\Program Files\YAMB\ or wherever it was that you chose to install the program to during setup).

Go back to the Mux tab, click Add and select your already-encoded XviD AVI file. The Import Settings dialog will show up. Make sure that Remove N-VOPs and Import only Video Track is selected. It can automatically detect the framerate from AVI files so you more than likely won't need to use the Force framerate option. Click OK and it'll go back to the main screen. Now to add your audio, click Add again and choose your audio, the dialog will pop up again; you won't even be able to access the N-VOPs or framerate options so don't worry about them, make sure the Import only Audio Track is selected and press OK. Now just click Mux and it'll do it's thing. That's it.

I downloaded the YAMB program above. I appreciated your very long and precise directions, but unfortunately I get an error when trying to use the program. "Error importing ___" and "Mux Failed" I only tried it with one file, and didn't restart my computer after installation which is probably the cause so I will try it again as soon as I get a chance.

I tried to use another program for converting to MP4 with the guide here: http://www.animemusicvideos.org/guides/ ... 64gui.html. That put my sync off even more than XviD. *Sigh* I don't think AAC audio has anything to do with it. It's supposed to be "more efficient than MP3."

I have yet to try the MKV program you suggested. I am confused though: It's required to convert the files to XviD with V-DubMod before using the programs you suggested, but if I am trying to get them to sync up better when XviD throws off the sync and converting to them to XviD before I put convert them to MP4 or MKV, it couldn't really fix the sync, could it?

Again, sorry for the late reply!

[Qyot27]

I am confused though: It's required to convert the files to XviD with V-DubMod before using the programs you suggested, but if I am trying to get them to sync up better when XviD throws off the sync and converting to them to XviD before I put convert them to MP4 or MKV, it couldn't really fix the sync, could it?

Well, I'm working off the assumption that it isn't XviD itself that's causing the problems, but rather the hacks needed to store XviD (more specifically, when used with B-frames) in AVI that are the source of the desync. The options for YAMB and MKVMerge that I outlined are meant to store the video stream the way it's supposed to be, which means no hacks, and hence there shouldn't be desync unless something else is wrong. It involves specifically analyzing the video and placing the frames correctly rather than trying to pack them together or do other wonky things with them.

I guess a simpler way of testing this would be to just disable B-frames entirely when you encode to AVI and see if that fixes it. If it does, you know the desync is the fault of the hacks needed to store B-frames in AVI. You'll take an efficiency hit, but if it's just that causing the problem, using MP4 or MKV should take care of it.

With zarx264gui, that's not even XviD you're dealing with - it's H.264. And no, AAC shouldn't cause more or less desync problems than MP3. As H.264 is more hardware-intensive, though, maybe that was simply a result of your computer's processor not keeping up with how fast it needs to go to decode the content smoothly.

[Kero777]

Thanks for your response.

Well, I'm working off the assumption that it isn't XviD itself that's causing the problems, but rather the hacks needed to store XviD (more specifically, when used with B-frames) in AVI that are the source of the desync.

I guess a simpler way of testing this would be to just disable B-frames entirely when you encode to AVI and see if that fixes it. If it does, you know the desync is the fault of the hacks needed to store B-frames in AVI. You'll take an efficiency hit, but if it's just that causing the problem, using MP4 or MKV should take care of it.

Nope: didn't seem to fix it. Maybe I have something checked off that's not supposed to be checked or something...?

The options for YAMB and MKVMerge that I outlined are meant to store the video stream the way it's supposed to be, which means no hacks, and hence there shouldn't be desync unless something else is wrong. It involves specifically analyzing the video and placing the frames correctly rather than trying to pack them together or do other wonky things with them.

I see. I'm still not quite sure how I'd convert the video before putting it through YAMB or MKVMerge. Every way I do it seems to make it off-sync.

With zarx264gui, that's not even XviD you're dealing with - it's H.264. And no, AAC shouldn't cause more or less desync problems than MP3. As H.264 is more hardware-intensive, though, maybe that was simply a result of your computer's processor not keeping up with how fast it needs to go to decode the content smoothly.

I do not think that is the case. I just bought a brand new computer and besides this problem, it seems to run very fast and smooth. *Sigh* I can't really disregard any possibilities though, because at this rate it could be any tiny little thing.

I also do not think it's my export from Vegas like Post-it suggested (like an error in a transition) because every video I export, transitions or not are off-sync after converting. Also, the lagarith and huffyuv exports play back 100% in-sync, but I can't be distributing those huge files.

*Sighs again* I'm going to try YAMB again in a few minutes. I bet it's going to be the tiniest little thing that I'm forgetting to do, someone will suggest it and I will feel like a complete idiot.