Welcome to Doom9's Forum, THE in-place to be for everyone interested in DVD conversion. Before you start posting please read the forum rules. By posting to this forum you agree to abide by the rules. |
25th May 2012, 10:30 | #1 | Link |
Registered User
Join Date: Dec 2008
Posts: 233
|
To 10bit or not to 10bit!
Hey all,
Just wanted to check opinion on whether 10bit x264 is now the way to go, bearing in mind that the decoder i'll be using (ffmpeg/XBMC) now supports 10bit. My main goal is to reduce file size compared to 8bit. Is there any reason why i shouldn't crack on and start using 10bit for my encodes from now on? Encode times are a bit longer, however not too fussed about that. Cheers |
25th May 2012, 10:52 | #2 | Link |
RipBot264 author
Join Date: May 2006
Location: Poland
Posts: 7,815
|
http://x264.nl/x264/10bit_02-ateme-w..._bandwidth.pdf
You must remember that 10bit won't play on any other device (TV / Media Players / PS3 ...) also DXVA won't work either. 10 bit will work only on HTPC (software decoding)
__________________
Windows 7 Image Updater - SkyLake\KabyLake\CoffeLake\Ryzen Threadripper |
26th May 2012, 23:25 | #5 | Link |
Derek Prestegard IRL
Join Date: Nov 2003
Location: Los Angeles
Posts: 5,989
|
I completely agree. AVC Intra / Ultra are the only places we'll see 10 bit H.264 in any sort of widespread use.
__________________
These are all my personal statements, not those of my employer :) |
31st May 2012, 04:07 | #8 | Link |
Registered User
Join Date: Nov 2003
Posts: 1,281
|
Some of us don't like conforming to how apple thinks we should do things
__________________
http://www.7-zip.org/ |
1st June 2012, 06:12 | #10 | Link |
interlace this!
Join Date: Jun 2003
Location: i'm in ur transfers, addin noise
Posts: 4,555
|
you'll need mainstream display devices that can reliably show the difference for a start.
10-bit is good as a mezzanine format, and for some odd corner-cases of the encoding world (anime is but a genre, fansubbers aren't the authority, though they're an interesting case. they also seem to believe that anime is the hardest thing to encode well, though this hasn't been true since the introduction of h.264. banding is only an issue if you insist on scrubbing out not only the noise, but most of the detail as well). i would LOOOVE it if i could buy a $400 TV that is accurate to 10 bits in all the channels. until then, 10-bit distribution is just one of those OCD settings, like --me tesa, well in the realm of diminishing returns.
__________________
sucking the life out of your videos since 2004 |
1st June 2012, 11:41 | #11 | Link |
Registered User
Join Date: Apr 2012
Posts: 38
|
You'd be surprised at the amount of compression with certain sources. With film, I've personally noticed a 5-10% reduction in file size, so it's probably not worth it, but with anime, I hear it's more -- maybe 20-30% -- which is quite significant.
|
1st June 2012, 17:19 | #12 | Link |
Moderator
Join Date: Jan 2006
Location: Portland, OR
Posts: 4,770
|
Relatd question: What video tools support decoding 10-bit from 10-bit H.264 bitstreams? Alas, most encoding tools don't even have 10-bit pipelines, so I fear those that can decode 10-bit H.264 might wind up truncating to 8-bit and going from there.
But yes, it would be a GREAT mezzanine alternative to the industry standard MPEG-2 (inefficient, generally less than pristine quality) and ProRes (HUGE!). |
1st June 2012, 17:22 | #13 | Link |
Moderator
Join Date: Jan 2006
Location: Portland, OR
Posts: 4,770
|
Also, has x264 or other H.264 encoders looked at retaining all 10 bits of 10-bit sources to the quantization stage, even when doing an 8-bit encode? It seems that having more precise data would enable the encoder to better determine when to dither and when not to, gaining some of the value of 10-bit encoding.
Essentially, a perceptually optimized in-loop dither. Now that the 10-bit source piepline exists for x264... |
1st June 2012, 19:12 | #14 | Link |
Skittle
Join Date: Mar 2008
Posts: 539
|
x264 is 16bit internally.
http://forum.doom9.org/showpost.php?...0&postcount=24 |
1st June 2012, 19:23 | #15 | Link | |
Moderator
Join Date: Jan 2006
Location: Portland, OR
Posts: 4,770
|
Quote:
But, by default, are 10-bit sources input at 10-bit into the 16-bit mode? If input is YV12, it's still only 8-bit. |
|
1st June 2012, 19:38 | #16 | Link | |
Registered User
Join Date: Jan 2007
Posts: 729
|
Quote:
Similarly, with 12bit bitdepth, IIRC some operations would even require moving to 32-bit integers, because 16bit ones wouldn't have enough headroom. As you can read there though, the values need to actually be clipped to stay within the bitdepth. So saying that x264 is "internally working in 16bit" is incorrect. Last edited by mandarinka; 1st June 2012 at 19:40. |
|
1st June 2012, 20:35 | #17 | Link |
Registered User
Join Date: Jul 2007
Posts: 552
|
x264's filter chain works at 8 or 16-bit depth depending from input and filters. Before sending it to libx264 (actual encoding) it is converted to 8 or 10-bit according to build version (downsampling is made with dithering). So no, actual dithering is made before encoding, not in-loop.
|
3rd June 2012, 03:48 | #20 | Link | |
Registered User
Join Date: May 2008
Posts: 40
|
Quote:
Sometimes there is banding even in the master itself (madoka, confirmed by mp3dom). That means fansubbers have to deband even if they would prefer not to (already grainy BD source), and 10bit helps a lot in preserving the gradients without going insane with debanding/addgrain. It's not that anime are difficult to encode, the problems lies in the fact that they are produced by incompetent people. And that's why the good ones started using 10bit, the vast majority of clueless rippers/encoders just followed because 10bit was the next cool thing. |
|
|
|