10bit x264 Encoding

[† L4ugh]

Since this seems to be a popular topic on some of the other forums I thought I'd start one here as well.

I've started doing some limited testing with the new 10bit x264 and it does seem as though the new format offers better compression for the same quality. I've been running small 5min test clips but even with them I'm seeing a difference in size with virtually no difference in quality.

Is anyone here testing this new 10bit format? If you are, what are your first impressions of it? Do you think you will be using it for all your future encoding?

I haven't really made up my mind on what I think yet, so I'm probably going to hold off on using it until it's supported more then it is now.

For those interested I'm going to post some info about the two most recent test I've done so far. I used a pretty high crf value so the quality really isn't that great. I'm going to run some more test tonight at a lower crf. I'll share the results of those test hopefully sometime tomorrow. The spoiler below contains the command line strings I used. The top one is the 10bit and the bottom one is the 8bit.

x264_10 --profile high10 --preset slower --tune animation --crf 26.0 --deblock 2:1 --qcomp 0.7 --trellis 1 --no-fast-pskip --output "D:\Encodes\Test[Hi10].mp4" "D:\Encodes\Scripts\Z.O.E. Idolo [Mini-Encode].avs"

x264_8 --profile high --preset slower --tune animation --crf 26.0 --deblock 2:1 --qcomp 0.7 --trellis 1 --no-fast-pskip --output "D:\Encodes\Test[Hi8].mp4" "D:\Encodes\Scripts\Z.O.E. Idolo [Mini-Encode].avs"

Below is a screen grab of the output from the strings above. I'm also uploading the test encodes to MF and some screen grabs encase anyone wants to check them out. It should also be noted that the tests are just video so there is no audio to the files offered below.

10bit Test Download

8bit Test Download

[zolockit]

What was your source? 10-bit is kind of meant for sources that are HD.

[† L4ugh]

I was going to add more test encodes today but since this topic really doesn't seem to be of any interest to anyone I'll save the upload time for something more productive.

What was your source? 10-bit is kind of meant for sources that are HD.

So far my sources are DVD. I really haven't read anywhere that the 10bit format couldn't be used for SD sources. Only thing I have read is that it is suppose to be more accurate at compressing the video then 8bit, and as long as that's the case I'll use it on any source I feel could use it.

Everything I've read so far seems to point to the purpose of 10bit as cutting down on banding while saving file size for same quality or offering greater quality for same file size. The only real difference I'm seeing from what is being mentioned on other forums like Doom9 is with the idea that it's suppose work best on anime content. The test I ran last night seem to point to a greater savings of file size coming from live action content rather then animated. The four clips I encoded last night (2 anime and 2 live action) showed more then twice as much savings in file size for live action between the 8bit and 10bit versions at a constant quality of 17. The clips were 4min each except for Vandread which somehow ended up being 3min 58sec.

Live Action CQ@17

Moon 8bit = 41.0mb

Moon 10bit = 35.8mb

Skyline 8bit = 56.7mb

Skyline 10bit = 50.9mb

Anime CQ@17

Vandread 8bit = 26.9mb

Vandread 10bit = 24.7mb

Z.O.E. Idolo 8bit = 44.4mb

Z.O.E. Idolo 10bit = 42.3mb

While 4 test is hardly enough to come to a conclusion. It does offer reason to do further testing. The 10bit format even seemed to help prevent artifacts in the dark and shadow regions of the live action videos. The anime content pretty much lived up to what is being mentioned on Doom9, less banding and smaller file size.

And yes, I'm also aware that encoding Skyline to 10bit isn't going to make the movie any more entertaining. XD

[ZeroPenguins]

But just a question, how long does it take you to encode them. I heard some people say it takes 4 hours for a 24 minutes 720p encode on an AMD quad core.

[† L4ugh]

Well, I don't have a quad core so I'm not really sure what the encoding time would be on one. I don't have any HD sources either, so I've been testing 10bit on my DVD rips. I'm not even sure what the encode times are for my sources because I usually run them at night while I'm asleep. I have watched them run long enough to gauge when they would be completed, and the 10bit usually has an eta about twice as long as the 8bit. All I can really tell you is that 10bit will take longer to encode then 8bit.

The problem I'm having now is XBMC doesn't support 10bit and won't support it in the next release either. I like the idea of being able to lower the size of my encodes while limiting the banding, but if I have to watch them with mpc-hc or vlc then it really defeats the purpose of archiving them. I also don't want to dig into the guts of XBMC just to set up an external player for 10bit content. Apparently 10bit will be added when the devs update to the newer ffmpeg that supports 10bit, but their's no eta on when that will happen.

[ZeroPenguins]

Well, I don't have a quad core so I'm not really sure what the encoding time would be on one. I don't have any HD sources either, so I've been testing 10bit on my DVD rips. I'm not even sure what the encode times are for my sources because I usually run them at night while I'm asleep. I have watched them run long enough to gauge when they would be completed, and the 10bit usually has an eta about twice as long as the 8bit. All I can really tell you is that 10bit will take longer to encode then 8bit.

The problem I'm having now is XBMC doesn't support 10bit and won't support it in the next release either. I like the idea of being able to lower the size of my encodes while limiting the banding, but if I have to watch them with mpc-hc or vlc then it really defeats the purpose of archiving them. I also don't want to dig into the guts of XBMC just to set up an external player for 10bit content. Apparently 10bit will be added when the devs update to the newer ffmpeg that supports 10bit, but their's no eta on when that will happen.

Oh ok, I suppose you're correct, I bet 10bit won't work on most media centres.

[Royce_666]

Well AMD is much slower as compared to intel thats why...

AMD quad core is as good as Intel Core 2 duo thats bcoz AMD doesnot release its products or upgrades it like Intel does....

try using Intel core i5 or i7 & see the difference...

I was also a AMD user untill i bought my core i5 processor..........

AMD is good for gaming ...

[ZeroPenguins]

Meh I prefer Intel myself, but AMD is also fine if I want to save some cash. Currently using an i7 920 and no issues yet.

[zolockit]

I'll just randomly reply to some of the stuff said all around.

Okay, yes you can use the profile on whatever sources, with whatever resolution, that you please, sure. But it takes up more decoding power on a pc that is limited to playing only SD resolution video to being with. It's why ideally people shouldn't bother. Someone like BN probably can't play hi10p@480p so where is the benefit? Encode sizes? Less banding?

Less banding does occur, but you're not showing examples of this. Also this decrease of banding sometimes comes at the cost of dot crawl like crap appearing iirc. Meh.

Use screenshot comparison to take shots of visible differences with using the 8-bit profile and the 10-bit profile. It's not really noticeable if you put them on separate images like that.

I asked about your source since your bright as hell command prompt had a [mini-encode] tag. I see you used crf 26, that's kind of low. Fast scenes will have horribad macroblocking low. If you want to be fair and give this a good trial comparison, use a lower value like 17-18.

>But just a question, how long does it take you to encode them. I heard some people say it takes 4 hours for a 24 minutes 720p encode on an AMD quad core.

It depends on how many filters you use with avs/x264 triggers/cpu power. Too abstract of a question. But 10-bit encoding apparently increases it by at least 10% of what it would normally be.

Which is why I want a sandy :<

[† An IP BreAKDoWN]

Personally, I won't start encoding in 10 bit until more media centers support it heh.

[ameanberg]

So, 10-bit for archiving or not? Or stick with 8-bit?

[† L4ugh]

Kind of depends on your preference. I don't think the filters are ready for 10bit encoding, and avisynth doesn't really support it either. You'll have to use the dither package and avs2yuv. Atleast if you intend to use the 16bit mod and output 16bit video to x264. Once you have it converted to 16bit you'll be very limited on which filters you can utilize because most are 8bit only. This might not be a problem if you have a really good source, but I've been noticing some haloing with my ripped dvd test. The format itself does seem to live up to what everyone else is saying, but I may end up waiting a while longer before I start encoding with 10bit x264. I would like there to be a few more 16bit filters to use with the dither package before I decide to go full 10bit. A version of avisynth that fully supports 10 or 16 bit video would be even better, but I'm not expecting that anytime soon. The amount of filters that would need updating is huge, and some are not only closed source but no longer maintained as well. They will most likely never make it to an updated version.

If you're wanting to know if you should be using it. I would recommend doing some 5-10min test encodes. If you're not finding anything wrong with the video, like haloing or other artifacts. Then it would probably be fine to use it for encoding, but you will need to make sure that the player you intend to use supports 10bit video. You can still run any 8bit filters you want at the start of the script. Then you can just add the 16bit conversion at the end, but if it causes haloing or other artifacts there isn't much you can do about it.

I'm still pretty new at all of this myself, so there is no guarantee that I'm even doing it right. The 10bit encodes I see coming out of some of the major encoder groups look pretty good. It could be that I'm still be missing something. I imagine the HD sources they're using are a pretty big part of it. I'm afraid that I won't have HD sources to test until I finally update my PC with a bluray drive.

[Koby]

The 10-bit encodes I'm seeing from other encoders have been extremely nice. The image is sharper, banding issues are near non-existent, and even less pixelation. As far as filters being unavailable, I haven't heard anything about that, but the encoders I get releases from seem to be doing fine with using all sorts of filters popping out test encodes and screencap comparisons.

If you want to archive, 10-bit is certainly going to allow better quality at the same size, but if you plan to play it on anything except your computer at this time then you'd better stick to 8-bit. Also people who's PC was barely able to keep up with 720p 8-bit will be unable to to keep up with 720p 10-bit since it uses more CPU to play.