x264 2-pass?

zurgel · Postby **zurgel** » 09 Mar 2007 23:38

Hi!

I don't know if this is the right channel.

My question is: When transcoding a video to H.264 (which is done by x264, right?) in GUI mode, how can I use 2-pass encoding?

Or do I have to do that on the commandline?

Postby **Jean-Baptiste Kempf** » 10 Mar 2007 01:24

This is very experimental. You can't do it yet with the GUI sorry.

zurgel · Postby **zurgel** » 10 Mar 2007 23:32

Ok, but is x264 (commandline) able to do 2-pass at all?

By the way, which lossless codec may I use for screen capture? Huffyuv does not seem to be supported - VLC always crashes when loading the files.

Postby **CloudStalker** » 11 Mar 2007 00:27

By the way, which lossless codec may I use for screen capture?

Hmm…isn’t PNG lossless? And I know for a fact that this is supported.

zurgel · Postby **zurgel** » 11 Mar 2007 02:07

Hmm…isn’t PNG lossless?

Yes it is. And both, VLC and Quicktime (which I often need), support PNG.

The problem is: I have to record in Windows. Would it be on my Mac everything would be a two click thing (SnapzX) but in Windows it's not: In Windows I use Camtasia and that relies on the Windows codecs.

For the recording I need a codec that's fast (CPU: AMD Sempron 3100+) and lossless. I don't know if PNG is fast. As far as I can tell from photo editing it's not but that may be due to my setting "maximum compression". But the other problem is: Where do I get it as a windows codec?

The Techsmith codec isn't lossless enough (which is paradox - not lossless enough... LOL) and it's not fast enough. Too many frame drops. Huffyuv provides good results but cannot be read in either Quicktime or VLC. eRightsoft's Super converts Huffyuv. But Super's x264 results quality is far behind Quicktime's H.264. I blame Super for that because I have the suspicion that the implemented x264 only does a 1-pass. Anyway, the quality of x264 through Super leaves a lot to be desired. And as far as I know the x264 commandline utility needs raw material, right? If I have to convert a lossless codec movie file into a raw movie first prior to encoding - well, then I would use Quicktime for that. I'm currently doing that but a video over half an hour produces too much raw data.

I have installed a lot of codecs and those which might be lossless are: PicVideo MJPEG (is it lossless??), PicVideo lossless jpeg, huffyuv of course and in ffdshow MJPEG (?), lossless JPEG and H.264 lossless (is that really lossless?!?! please tell me!). I will still have to try them out. I hope that any of those can be read by VLC, x264 and/or Quicktime and is fast enough to avoid frame drops.

The result of the screen recording should be H.264 in a mp4 or mov container.

By the way, until now I cannot confirm x264s superior quality which was praised so much in Doom9s Codec Shootout. Until now, Quicktime H.264 seems to be way better. I really hope that it is only due to x264 not doing a 2-pass or other Super issues but I don't know. I emailed erightsoft to get info about their x264 implementation.

Another question: Does anyone have some better ideas about programs, codecs, etc. and wants to share them with me?

Postby **CloudStalker** » 11 Mar 2007 03:12

Ha! I read all the way through this post and got lost at “CloudStalker wrote:” – huh, even before my own quote.

Seriously though, I’m still trying to learn more about how the different audio/video codecs work, hence, I’m joining the doom9 forums as-well. Sorry I coudn't help.

Another question: Does anyone have some better ideas about programs, codecs, etc. and wants to share them with me?

What type of programs are you looking for? I might actually be able to help out there.

zurgel · Postby **zurgel** » 11 Mar 2007 05:01

What type of programs are you looking for?

Well, the term "another question" might be a bit misleading. I just wonder which codec I should use for lossless compression that other encoding applications (or Quicktime) understand, which lossless codecs are known to be fast and efficient, which program might be more suitable for encoding, "how do I get x264 working in 2-pass with a GUI", etc. Basically, I'd just like to know what you think about all the stuff I wrote and maybe you can help me to get everything working together in a better way.

Postby **CloudStalker** » 11 Mar 2007 05:31

The term “I might actually be able to help out there.” Also might be misleading considering that I can’t actually help out in this situation, sorry. I’m not sure what program you can use, and I know little about lossless video codecs (more about lossless audio codecs though). So I’ll be doing my research on video codecs and hopefully be able to help out then. Until then, probably someone else will be able to help you out. Sorry again if I appeared to know what I was talking about, because I don’t, but I’m getting there.

zurgel · Postby **zurgel** » 11 Mar 2007 12:01

Sorry again if I appeared to know what I was talking about

No problem, I take the good will for the deed.

Postby **Jean-Baptiste Kempf** » 11 Mar 2007 18:43

Ok, but is x264 (commandline) able to do 2-pass at all?

Yes. VLC is able since a few days to do x264 2-pass encoding in the dev version.

zurgel · Postby **zurgel** » 11 Mar 2007 19:16

[...]since a few days[...]

Um... alright, then please tell me how come that doom9 codec shootout 2005 concludes that x264 is a better codec than Quicktime H.264 when 2-pass and other quality options were not available for x264 at that time. I'm a little confused and I guess you can understand why.

Postby DJ » 11 Mar 2007 19:33

Second pass encoding has been available in the x264 svn for a very long time. It just hasn't been available in VLC. Mainly because of the normal usage of VLC.

zurgel · Postby **zurgel** » 11 Mar 2007 21:02

I'm sorry. I overread the "VLC now can"... Seems as if I was too focused on the word "x264"...

By the way, what do you think: are the tests and results of the codec shootout on Doom9 really appropriate?

Postby DJ » 11 Mar 2007 22:26

are the tests and results of the codec shootout on Doom9 really appropriate?

I guess anyone has the right to conduct a shootout and express their opinion.

I use x264 because I believe it to be the most compatible h.264 encoder and gives me the ability to do enhancements with my editor and realize this in the end product. But I seldom use VLC for encoding h.264.

zurgel · Postby **zurgel** » 11 Mar 2007 23:19

I guess anyone has the right to conduct a shootout and express their opinion.

No doubt about that! What I meant was: Do you think that the tests deliver results that cannot be doubted or could somebody else maybe have different results? In short, do you think the test methods really reveal which codec performs best? I'd like to know how somebody who knows more about the matter than me evaluates that.

By the way, I got an answer in the SUPER(C) forum and 2-pass is not supported in the program, because - as they say -

it requires 43% more encoding time to provide 2~4% of file size reduction

Postby DJ » 12 Mar 2007 00:24

The shootouts are done once a year and the conditions for the process are well spelled out. I guess if you change the conditions under which anything is tested you can change the results. But if the premise is to find the best encoder and not promote one, then I would expect unbiased conditions.

zurgel · Postby **zurgel** » 12 Mar 2007 10:41

Ok. My goal of all the questions and recherche was to find out which codec really is best and which one I should use. Nothing more than that.

So, if I should use x264, how can I get the most out of it? Should I wait for VLC to officially get 2-pass support and more options or can you recommend another encoding program? x264 commandline has some restrictions concerning the input format... What about Mencoder?

By the way, can you also tell me which codec is best for lossless screen capture? MJPEG, lossless JPEG or H.264 lossless or another? Again, AMD Sempron 3100+ is my CPU on Windows, so the codec has to be fast while capturing.

I'm sorry if the thread deals with more subjects than I first thought (x264, 2-pass, best codec, encoder programs, lossless codecs, ...). I hope that's ok.

Postby DJ » 12 Mar 2007 20:10

h.264 is one of the newest codecs around. It was ratified as the codec of choice for the Blue Ray disks and players. It supports all of the new progressive standards as well as the interlaced standards. However it is a work in progress and not all vendors are compatible with each other nor do they have the same place in their progression of the format. This includes VLC.

I have chosen x264 because it offers me versatility and compatibility with the widest variety of decoders. However it takes time to learn how to use it to gain the desired results. If you are a person that likes to jump to the end and doesn't like to learn the middle this codec is NOT for you.

The Doom 9 forums is one of the best places to get started with h.264.

zurgel · Postby **zurgel** » 20 Mar 2007 21:10

Yes. VLC is able since a few days to do x264 2-pass encoding in the dev version.

Which one of the nightlies is that?

zurgel · Postby **zurgel** » 20 Mar 2007 21:12

If you are a person that likes to jump to the end and doesn't like to learn the middle this codec is NOT for you.

Well, actually I learnt most of the middle now...

zurgel · Postby **zurgel** » 21 Mar 2007 14:22

Sorry if I ask again but I'd like to know...

Yes. VLC is able since a few days to do x264 2-pass encoding in the dev version.

Which one of the nightlies is that? Or isn't it a SVN?

Postby **Jean-Baptiste Kempf** » 21 Mar 2007 16:28

all. latest.

The VideoLAN Forums

x264 2-pass?

x264 2-pass?

Who is online