XviD Quantizer Numbers

[SadaraX]

I am using Avidemux to encode my XviD in single pass quantizer mode. I was wondering if it is possible to set the rate to 1? This is not a direct Avidemux questions, more of a question relating to whether or not 1 is a valid number for a rate in the quantizer feature in XviD.

Thanks in advance. BTW, I already asked at the avidemux forums, they are not sure.

[Sharktooth]

q1 is valid but it will produce a huge file with similar quality to q2.
q1 is almost useless unless used with special designed custom quantization matrices.

[SadaraX]

q1 is valid but it will produce a huge file with similar quality to q2.
q1 is almost useless unless used with special designed custom quantization matrices.

I appreciate the information. I have been wondering about this for a while, because the avidemux developers were wondering whether or not they should allow people to use 1. Currently they have the range limited to 2-31.

[Teegedeck]

In the VfW XviD defaults, quant=1 is allowed. The only reason for that is the encredible and annoying amount of complaints about 'undersizing' that we used to get on the forum. Some folks don't understand the concept of a 'saturation point'.

If it weren't for that, limiting quantizers from 2 to 31 would be the only sane thing to do. Quant=1 is only there to eat up bitrate; higher quality usually comes with lower-coefficient custom quantization matrices, not with using quant=1 with the standard matrices.

As limiting quantizers in Avidemux appareantly doesn't cause another flood of 'undersizing-complaints' here, I'd say, they should keep it 2-31.

[SadaraX]

As limiting quantizers in Avidemux appareantly doesn't cause another flood of 'undersizing-complaints' here, I'd say, they should keep it 2-31.

I will be certain to tell the developers that, because learning this is pretty the whole reason that I asked.

[Teegedeck]

I'm especially happy to hear from XviD's Linux userbase here. Glad to help. :)

Can we expect Avidemux to expose all XviD options in a new release? I've never really used Avidemux because it cannot load custom quantization matrices.

Edit: You know, I'll be missing something like a full-blown Linux MeGUI/VirtualDub equivalent by the time we get AviSynth 3 on Linux. This will be the point when I'm gonna get the craving to do everything (editing, encoding to XviD and x264) on the Linux machine. So please excuse me when I'm (trying) to get a bit pushy here. ;)

[SadaraX]

I'm especially happy to hear from XviD's Linux userbase here. Glad to help. :)

Can we expect Avidemux to expose all XviD options in a new release? I've never really used Avidemux because it cannot load custom quantization matrices.

The custom matrices have not been addressed actually (this is the first time I have heard about it). Beyond those, I am fairly certain Avidemux can do all the other encoding options. (Correct me if I am wrong. If you like, I will post screen shots of the available options).

The plans for avidemux in the future are thus: 1) finish the implementation of the mp4 format. 2) Modernize the XviD codec configure interface (I suppose we could add the matrices there). 3) Add the rest of the options for x264/h264. I should note that items 2 and 3 really don't have a set priority and may be done in reverse order or side by side.

Edit: You know, I'll be missing something like a full-blown Linux MeGUI/VirtualDub equivalent by the time we get AviSynth 3 on Linux. This will be the point when I'm gonna get the craving to do everything (editing, encoding to XviD and x264) on the Linux machine. So please excuse me when I'm (trying) to get a bit pushy here. ;)

Speaking of the avisynth 3, I know that there are plans to fully integrate that into Avidemux, when it becomes available. If I remember correctly, version 3 will be free of all Microsoft Windows specific code. Also it looks like it will be easier to add the Avisynth v3.0 code/libraries into Avidemux. Mean himself has expressed plans to do this eventually and he sounded hopeful that it would not be too difficult.

I find Avidemux to be close to Virtualdub in its use. I used VDub a ton back my windows days, and now I use linux. On a side note concerning features I am trying to see added to Avidemux, I am hoping to get:

1) Soft-subtitles
2) MKV format
3) eventually I would like to see a better multi-audio track system
4) Allows for VBR audio (if only external file input)
5) Codec configuration option pre-set saving
6) Better job list/queue system (simple GUI and feature improvements, nothing major)

There are also some bugs in the LPCM and AC3 type audio codec/formats we have to fix as well, though they are minor. I really don't write much code right now (meaning I written VERY little), but I am hoping to do more in the future.

The main programmer of Avidemux (Mean) is currently in the process of moving into his new home/apartment right now, so he does not have constant internet yet. Thus there has not been many updates to the SVN files for a week or more, but he's been working on quite a bit at home and I except when he returns there will be many updates. I am hoping he will finish the mp4 code soon, he sounds like he will be.

[Sharktooth]

what's the official web of avidemux? i found 4 or 5 different websites on google...

EDIT: ok, nevermind... those are all mirrors :)

[Teegedeck]

The more I read about it, the more I like it. :) I see that TDeint has already been integrated. So there's one important function that I'd need already implemented. Nice, nice. Keep up the good work!

Edit: MKV output would be great alright (though I can always use mkvmerge, of course) and, yeah, audio encoding is what I feel could really use improvement.

[Teegedeck]

Important things to add to the XviD4 config in Avidemux:

b-frame settings (offset, ratio, sensitivity)
zones settings
first pass settings; some behaviour could simply be changed in your automated 2-pass (the first pass can be done much faster with little quality difference), but some would always need manual handling, I think (the first pass should ideally be encoded at a constant quantizer that is near the average quantizer of the 2nd pass)

[SadaraX]

Edit: MKV output would be great alright (though I can always use mkvmerge, of course) and, yeah, audio encoding is what I feel could really use improvement.

Do you use windows or linux Teegedeck? I just discovered a really nice mkv GUI program for linux (though it may have been there for a long time). Previously I was doing everything on the command line.

Important things to add to the XviD4 config in Avidemux:

b-frame settings (offset, ratio, sensitivity)
zones settings
first pass settings; some behaviour could simply be changed in your automated 2-pass (the first pass can be done much faster with little quality difference), but some would always need manual handling, I think (the first pass should ideally be encoded at a constant quantizer that is near the average quantizer of the 2nd pass)


When the XviD config update comes along, I will be sure to try to get these address, though I admit I do not really understand your part about the first/second pass improvements.

[Teegedeck]

Do you use windows or linux Teegedeck?Windows for encoding, Linux (SUSE) for the rest. But I'm a dumb GUI-user, couldn't compile my own shorts.
I just discovered a really nice mkv GUI program for linux (though it may have been there for a long time). Previously I was doing everything on the command line. Any chance it comes as an rpm?
When the XviD config update comes along, I will be sure to try to get these address, though I admit I do not really understand your part about the first/second pass improvements.Thanks again. :) Mainly I was about the 1st pass in Avidemux currently using the same settings as the 2nd pass (or so it seems to me); that's very good in a way and known as the 'full quality first pass' option in XviD's VfW config. But for people who use quite high-quality settings that results in a very slow first pass. It's really not necessary for the 1st pass to use VHQ=4 for example. Someone who uses all the HQ options can get a speedup of about 80 percent for the first pass if that one runs without GMC, QPel and chroma ME, perhaps engages the 'turbo' switch even (using faster algos), lowers ME precision to '5' and, most importantly, never sets VHQ mode higher than '1' (mode decision). The filesize discrepancy should still not be that big. Quantizer distribution in 2nd pass will still be good, and very good (almost constant quantizer if you don't use curve compression) if you've used a constant quantizer in first pass that is quite close to what you could expect for average quant in second pass. Have a look at Didée's posts in this thread (http://forum.doom9.org/showthread.php?t=83061) for an explanation.

[SadaraX]

Windows for encoding, Linux (SUSE) for the rest. But I'm a dumb GUI-user, couldn't compile my own shorts. Any chance it comes as an rpm?

What, Avidemux? Probably. In fact, I'm sure about it. www.avidemux.org, pick a mirror and download what you want. If not, we can probably help you compile. I compile from the SVN archives fresh almost daily.

Thanks again. :) Mainly I was about the 1st pass in Avidemux currently using the same settings as the 2nd pass (or so it seems to me); that's very good in a way and known as the 'full quality first pass' option in XviD's VfW config. But for people who use quite high-quality settings that results in a very slow first pass. It's really not necessary for the 1st pass to use VHQ=4 for example. Someone who uses all the HQ options can get a speedup of about 80 percent for the first pass if that one runs without GMC, QPel and chroma ME, perhaps engages the 'turbo' switch even (using faster algos), lowers ME precision to '5' and, most importantly, never sets VHQ mode higher than '1' (mode decision). The filesize discrepancy should still not be that big. Quantizer distribution in 2nd pass will still be good, and very good (almost constant quantizer if you don't use curve compression) if you've used a constant quantizer in first pass that is quite close to what you could expect for average quant in second pass. Have a look at Didée's posts in this thread (http://forum.doom9.org/showthread.php?t=83061) for an explanation.

I will have a look at that, since I think I understand a little better, but not fully. If it is something so important, hopefully it can be addressed in the XviD and h264 update that will be coming soon.

[Sharktooth]

The speedup for the first pass can be "massive"... so, yes, it's quite important :)

[SadaraX]

The speedup for the first pass can be "massive"... so, yes, it's quite important :)

Then I will definately look into this further and hopefully when the time comes I will be able to pester Mean to make the necessary adjustments.

[sysKin]

Then I will definately look into this further and hopefully when the time comes I will be able to pester Mean to make the necessary adjustments.

Fast First Pass should happen automatically, unless there's something to prevent it. If you just activate 2pass1 plugin and start encoding, you should get a fast 1st pass.

VfW's "full quality 1st pass" works by pretending that entire movie is a quant2 zone. It's a trick.

[Teegedeck]

Call me a fool because I am! I must have forgot to activate QPel and GMC on the sample I encoded with Avidemux or something because I'm testing again now, and everything seems to be as it should be; second pass noticeably slower!?! Yes, I tested only once before, and sloppily. Is a different arrangement of switches in Avidemux' GUI enough to confuse me to the point that I forget to activate some switches or did I press cancel instead of OK after modifying settings? Anyway, bloody stupid of me. Forget it and paint whiskers on me while I sleep.

I'm very sorry indeed for the unnecesary call for improvements there.
:o
:stupid:

P.S. SadaraX, I meant an RPM for the all-in-one-MKV-application you mentioned.

[SadaraX]

Call me a fool because I am! I must have forgot to activate QPel and GMC

I really don't care for QPel, do you feel it makes a real difference for your video quality?

on the sample I encoded with Avidemux or something because I'm testing again now, and everything seems to be as it should be; second pass noticeably slower!?! Yes, I tested only once before, and sloppily. Is a different arrangement of switches in Avidemux' GUI enough to confuse me to the point that I forget to activate some switches or did I press cancel instead of OK after modifying settings? Anyway, bloody stupid of me. Forget it and paint whiskers on me while I sleep.

I'm very sorry indeed for the unnecesary call for improvements there.

Oh, well, that's alright. Its better that there is no need for improvement than otherwise. Sorry to make you speak about it again, but just to clarify, I do not need to talk to Mean about speeding up the 1st/2nd pass on XviD (on anything we mentioned in this thread)?

P.S. SadaraX, I meant an RPM for the all-in-one-MKV-application you mentioned.

The program is called "MKV Tool *nix" (mkvtoolnix)
http://www.bunkus.org/videotools/mkvtoolnix/downloads.html

After you get that installed, run the command 'mmg' for the mkv-tool GUI.

You said you're not much into Linux, do you know how to use the apt system? If you are using redhat, you may want to use their apt-rpm system to automatically install the program, though you may have to add their download repository to your apt-package list.