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.

 

Go Back   Doom9's Forum > Video Encoding > MPEG-4 AVC / H.264

Reply
 
Thread Tools Search this Thread Display Modes
Old 31st August 2011, 18:42   #1  |  Link
W3ird_N3rd
Registered User
 
W3ird_N3rd's Avatar
 
Join Date: Feb 2006
Posts: 45
How to keep compatibility with hardware players?

I encode some h.264 movies from time to time, it would be nice if I could keep them compatible with hardware players. Like videocard-hardware decoding, mediaplayers in/for TVs, maybe even phones. You never know what I want to play the file on in the future.

Obviously I don't want to sacrifice too much quality, but leaving out some obscure options that don't improve the quality much anyway is ok.

I mostly use mencoder or avidemux. What options should I use, or stay far from? And is there any way to check if my file is compatible, without actually buying hardware decoders?

Or is this all obsolete today? In the old days, you just made sure you didn't use Qpel and GMC on your XviD and you'd be fine. With h.264, things are obviously different, but I'm not sure in what way.

It would also be nice to know what settings the "scene" uses, as their files generally seem to play on anything.

(I did search but could not quite find what I was looking for)
W3ird_N3rd is offline   Reply With Quote
Old 31st August 2011, 19:05   #2  |  Link
nurbs
Registered User
 
Join Date: Dec 2005
Posts: 1,460
You should stick to a level, apart from some exotic things that you could never turn on without using obscure options that's the only thing that matters for compatibility. Level 4.1 works on most non-mobile hardware and some newer cell phones. The AppleTV is a notable exception there. Level 3.1 works on even more including AppleTV, iPhone (3GS upward IIRC) and more other phones. You'll be restricted to 720p using that. You can read about the level restrictions on Wikipedia. The restrictions are largely on resolution, framerate and number of reference frames. It also restricts bitrate, but that won't be a real limitation in most backup scenarios. Just make sure you set VBV maxrate and bufsize accordingly to be on the safe side.

The scene rules are somewhat decent these days, but there is no reason to stick to them if your main goal is hardware compatibility, plus they are bordering on Rule 6 territory around here. The other stuff in there is just about encoding settings and filesizes. For the former you have the inbuilt x264 presets and tunings and I don't see why anyone would stick to the scene sizes unless they were targeting CD or DVD size anyway. If you don't do that you should just find a combination of --preset, --tune and --crf you are confortable with and not worry about sizes.

A sample command line for x264 itself that works on many devices with 720p video would be:
x264 --preset slow --tune film --crf 21 --vbv-maxrate 17500 --vbv-bufsize 17500 --level 3.1 -o output.mkv input.avs

You'll have to find a way to adapt that for mencoder.

Last edited by nurbs; 31st August 2011 at 19:16.
nurbs is offline   Reply With Quote
Old 31st August 2011, 22:04   #3  |  Link
CarlEdman
Registered User
 
Join Date: Jan 2008
Posts: 185
I agree generally, with @nurbs, except I've had a fair amount of trouble with profile 3.1 with Apple Devices (including the current iPhone and iPad), but not with profile 3.0. As that matters a great deal to my family, I've gone back to encoding my standard-def content to level 3.0.
CarlEdman is offline   Reply With Quote
Old 31st August 2011, 22:38   #4  |  Link
nurbs
Registered User
 
Join Date: Dec 2005
Posts: 1,460
I don't actually own any Apple devices, I just mentioned them because they are pretty popular. Level 3.1 is what Handbrake uses for the newer ones, maybe with some stricter VBV restrictions and possibly turning off weightp, I haven't checked. Anyway, since Handbrake is popular I'm sure their presets work so it's probably a good idea to if that's your target.
Personally I use 3.0 for my SD stuff and 3.1 for Blu Rays that I downscale to 720p.
nurbs is offline   Reply With Quote
Old 1st September 2011, 01:53   #5  |  Link
W3ird_N3rd
Registered User
 
W3ird_N3rd's Avatar
 
Join Date: Feb 2006
Posts: 45
Thanks nurbs and CarlEdman!

I didn't mean to break rule 6, this is not about illegal content, I just wondered if the settings from the "scene" (who most probably have been spending quite some time finding good and compatible settings) might be useful for me.

So as long as I get something from x264 like:

x264 [info]: profile High, level 3.0

Up to 4.1 (or 3.1 for Apple) I should be good, right? I've now made some encoding lines for SD at 3.0, 720p on 3.1 and 1080p at 4.1. Although I likely won't be using 1080p as that'll take forever on my X2 5600+ 2.9Ghz.

CarlEdman, thanks for pointing out problems with Apple and 3.1. I'm not really planning on buying Apple, but it would be nice to stay compatible, just in case. Looking at the handbrake profiles, many (especially slightly older) Apple devices don't even support CABAC. Well I'm not going to turn that off.

The iPhone4/iPad profile does not have any special options. In fact, it passes no extra options whatsoever to x264. Only reference frames and B-frames are both set to 3, that could be either because that's the highest found in any Handbrake profile, or because iPad/iPhone4 supports no more.

I'll keep the SD-stuff to 3.0, that's what I'll be encoding mostly for the forseeable future.

I've made a 3.1 sample, this should play on an iPhone4/iPad/AppleTV2: http://www.mediafire.com/?rrmp66hicfnznc3 (don't worry, it's Creative Commons!)

Mencoder lines used for this:
Code:
mencoder "input" -o "output" -ovc x264 -x264encopts bitrate=3500:pass=1:subme=3:frameref=1:bframes=3:threads=auto:mixed_refs:b_adapt=2:direct=auto -nosound

mencoder "input" -o "output" -ovc x264 -x264encopts bitrate=3500:pass=2:subme=6:frameref=3:bframes=3:threads=auto:mixed_refs:no-fast-pskip:8x8dct:direct=auto:trellis=1:vbv-maxrate=16500:vbv-bufsize=17000 -nosound
If it doesn't play I'm going to be confused.
W3ird_N3rd is offline   Reply With Quote
Old 1st September 2011, 07:32   #6  |  Link
nurbs
Registered User
 
Join Date: Dec 2005
Posts: 1,460
Quote:
Originally Posted by W3ird_N3rd View Post
I didn't mean to break rule 6, this is not about illegal content, I just wondered if the settings from the "scene" (who most probably have been spending quite some time finding good and compatible settings) might be useful for me.
If you are interested the scene wants level 4.1, settings not faster than --preset slow and some really stupid rules on what CRF you can use, that's it.
nurbs is offline   Reply With Quote
Old 1st September 2011, 11:41   #7  |  Link
nm
Registered User
 
Join Date: Mar 2005
Location: Finland
Posts: 2,641
Quote:
Originally Posted by W3ird_N3rd View Post
Mencoder lines used for this:
Code:
mencoder "input" -o "output" -ovc x264 -x264encopts bitrate=3500:pass=1:subme=3:frameref=1:bframes=3:threads=auto:mixed_refs:b_adapt=2:direct=auto -nosound

mencoder "input" -o "output" -ovc x264 -x264encopts bitrate=3500:pass=2:subme=6:frameref=3:bframes=3:threads=auto:mixed_refs:no-fast-pskip:8x8dct:direct=auto:trellis=1:vbv-maxrate=16500:vbv-bufsize=17000 -nosound
MEncoder supports x264 presets and tunings these days, and it does fast first pass by default.
nm is offline   Reply With Quote
Old 1st September 2011, 19:10   #8  |  Link
W3ird_N3rd
Registered User
 
W3ird_N3rd's Avatar
 
Join Date: Feb 2006
Posts: 45
But how fast? If I lower subme to 1 on the first pass I see a big degradation in picture quality.

I'm also reading 8x8dct would already be standard.

Still, I used to have many more options that were no longer needed.
W3ird_N3rd is offline   Reply With Quote
Old 1st September 2011, 19:38   #9  |  Link
nm
Registered User
 
Join Date: Mar 2005
Location: Finland
Posts: 2,641
Quote:
Originally Posted by W3ird_N3rd View Post
But how fast? If I lower subme to 1 on the first pass I see a big degradation in picture quality.
It gets lowered to 2, not 1.

Quote:
I'm also reading 8x8dct would already be standard.
Yes, x264 encodes in high profile by default.
nm is offline   Reply With Quote
Old 2nd September 2011, 02:12   #10  |  Link
W3ird_N3rd
Registered User
 
W3ird_N3rd's Avatar
 
Join Date: Feb 2006
Posts: 45
Quote:
Originally Posted by nm View Post
It gets lowered to 2, not 1.
I ran a test with subme=2 on the first pass, but it's still slighty blockier than subme=3 on the first pass.

I'm going to stick with subme=3.
W3ird_N3rd is offline   Reply With Quote
Old 2nd September 2011, 08:20   #11  |  Link
nm
Registered User
 
Join Date: Mar 2005
Location: Finland
Posts: 2,641
Quote:
Originally Posted by W3ird_N3rd View Post
I ran a test with subme=2 on the first pass, but it's still slighty blockier than subme=3 on the first pass.
Did you try using the same parameters (except pass=N) for both passes and let x264 lower the settings for you (with older MEncoder versions, you also need turbo=1, but I'd recommend updating instead)?

If you already happen to use current MEncoder, subme will get lowered to 2 by default when you have pass=1 in the command line. You need to use parameter slow_firstpass to avoid that.

Last edited by nm; 2nd September 2011 at 08:31.
nm is offline   Reply With Quote
Old 3rd September 2011, 14:36   #12  |  Link
W3ird_N3rd
Registered User
 
W3ird_N3rd's Avatar
 
Join Date: Feb 2006
Posts: 45
Quote:
Originally Posted by nm View Post
Did you try using the same parameters (except pass=N) for both passes and let x264 lower the settings for you (with older MEncoder versions, you also need turbo=1, but I'd recommend updating instead)? If you already happen to use current MEncoder, subme will get lowered to 2 by default when you have pass=1 in the command line. You need to use parameter slow_firstpass to avoid that.
Damn, you're right. So where did the extra compression artefacts come from? Maybe from opening the player twice.

I'm really confused. I think I'm going crazy. But that's impossible of course. I already was.
W3ird_N3rd is offline   Reply With Quote
Reply

Tags
compatibility, h264, options, x264

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 11:49.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.