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 > High Efficiency Video Coding (HEVC)

Reply
 
Thread Tools Search this Thread Display Modes
Old 15th January 2019, 10:10   #6641  |  Link
asarian
Registered User
 
Join Date: May 2005
Posts: 1,372
Quote:
Originally Posted by sneaker_ger View Post
Oh, I'm sure the difference will be noticable to consumers. Simply because authors will make it so, not because it's superior. Just like in the past authors used different mixes for AC3 and DTS tracks on the same DVD. It's all about marketing.
Having an HD Amp myself, trust me, you can hear de difference! Try listening to Blade Runner, the Final Cut, with full HD audio, or the same movie, just with DD5.1, and I guarantee you that everything below HD audio will sound crap from there on in.
__________________
Gorgeous, delicious, deculture!
asarian is offline   Reply With Quote
Old 15th January 2019, 10:53   #6642  |  Link
jd17
Registered User
 
Join Date: Jun 2017
Posts: 89
Quote:
Originally Posted by asarian View Post
Having an HD Amp myself, trust me, you can hear de difference! Try listening to Blade Runner, the Final Cut, with full HD audio, or the same movie, just with DD5.1, and I guarantee you that everything below HD audio will sound crap from there on in.
That is not a very good argument against what sneaker said.

How do you know both mixes are based on the same mastering?
How do you know the DD-mix is not willingly different/worse than the HD mix?
Are you comparing identical speaker layouts (both just 5.1)?
Are you sure there is no dynamic compression in the DD-mix?
Are the volume levels identical?
Is the DD-mix limited in bitrate (384/448) or does it use the full 640kbit/s potential?

If you want a comparison of codec audio quality only, try encoding your own DD-mix from the HD-audio stream, considering all the factors above.
Even then, you cannot be sure in case of AC-3, because people claim that the original, commercial encoder is superior to those available freely...
jd17 is offline   Reply With Quote
Old 15th January 2019, 11:01   #6643  |  Link
asarian
Registered User
 
Join Date: May 2005
Posts: 1,372
Quote:
Originally Posted by jd17 View Post
That is not a very good argument against what sneaker said.

How do you know both mixes are based on the same mastering?
How do you know the DD-mix is not willingly different/worse than the HD mix?
Are you comparing identical speaker layouts (both just 5.1)?
Are you sure there is no dynamic compression in the DD-mix?
Are the volume levels identical?
Is the DD-mix limited in bitrate (384/448) or does it use the full 640kbit/s potential?

If you want a comparison of codec audio quality only, try encoding your own DD-mix from the HD-audio stream, considering all the factors above.
Even then, you cannot be sure in case of AC-3, because people claim that the original, commercial encoder is superior to those available freely...
Blade Runner is just one example. Let's not derail this thread too much, but I can assure you, that once you go HD audio, you'll never want to go back, ever. And why should that surprise anyone?! A typical DTS-MA/TrueHD track is often larger in size than an entire DVD! With bitrates around 10x higher as regular DTS, the superiority of HD audio is a no-brainer, far as I'm concerned.
__________________
Gorgeous, delicious, deculture!
asarian is offline   Reply With Quote
Old 15th January 2019, 12:12   #6644  |  Link
excellentswordfight
Lost my old account :(
 
Join Date: Jul 2017
Posts: 115
Quote:
Originally Posted by asarian View Post
And why should that surprise anyone?!
Cause 48Khz 16bit audio is very much sufficient for human hearing, and if you have enough experience of audio compression you know that there is several codecs that can achive very close to transperent audio with say 64kbps per channel (and most formats are above that!). I've encoded several surround tracks form lossless to multiple formats, you be surprised how little it affects hearable fidelity.

With that said, I'm sure that the HD-track sounds better for you, but most of that doesnt come from the higher specs (sample rate, bit depth and losslessness)

Last edited by excellentswordfight; 15th January 2019 at 12:17.
excellentswordfight is offline   Reply With Quote
Old 15th January 2019, 14:37   #6645  |  Link
jd17
Registered User
 
Join Date: Jun 2017
Posts: 89
Quote:
Originally Posted by asarian View Post
With bitrates around 10x higher as regular DTS, the superiority of HD audio is a no-brainer, far as I'm concerned.
Nobody questions that lossless - in theory, or better measurably - is always better.
However, this is a forum that pretty much evolves around compression efficiency, i.e. saving bits where we don't see or hear it.

This is why I (and plenty others here too) take these lossless audio streams and compress them to 200-600kbit/s AAC or opus.

And while these codecs are obviously far superior to the ancient AC-3, you'd be surprised how good 640kbit/s Dolby Digital really is.
Accordingly, if the same master (and volume) is used, you would most likely fail in telling TrueHD apart from Dolby Digital, if you don't know which is playing.
jd17 is offline   Reply With Quote
Old 15th January 2019, 15:31   #6646  |  Link
asarian
Registered User
 
Join Date: May 2005
Posts: 1,372
Quote:
Originally Posted by jd17 View Post
Nobody questions that lossless - in theory, or better measurably - is always better.
However, this is a forum that pretty much evolves around compression efficiency, i.e. saving bits where we don't see or hear it.

This is why I (and plenty others here too) take these lossless audio streams and compress them to 200-600kbit/s AAC or opus.

And while these codecs are obviously far superior to the ancient AC-3, you'd be surprised how good 640kbit/s Dolby Digital really is.
Accordingly, if the same master (and volume) is used, you would most likely fail in telling TrueHD apart from Dolby Digital, if you don't know which is playing.
'CD Quality' is 44.1 KHz/16 bit audio, generally considered 'very good' for music. Movies are a different thing, though. AC3 (aka DD 5.1) yields reasonable results at (almost always) 640kbps. But the difference between DTS-MA/TrueHD vs. AC3 is, well, unimaginably high. Believe me, I was in the same camp as you, one day, thinking you wouldn't be able to tell the difference... until I got an actual HD Amp. The fullness of the track when you switch to HD audio is staggering -- to the point where I can barely bear to listen to AC3 any more. In fact, for every Blu-ray I order (unless it's some sort of vintage deal), I first check to see whether it comes with HD Audio. If not, I simply don't buy it.

I'm not familiar with compressing audio 'to 200-600kbit/s AAC or opus' myself, so I'll take your word on those codecs.
__________________
Gorgeous, delicious, deculture!
asarian is offline   Reply With Quote
Old 15th January 2019, 15:46   #6647  |  Link
nevcairiel
Registered Developer
 
Join Date: Mar 2010
Location: Hamburg/Germany
Posts: 9,818
Quote:
Originally Posted by asarian View Post
But the difference between DTS-MA/TrueHD vs. AC3 is, well, unimaginably high.
Except on a technical level it really is not.

At least DTS has a "core" you can use for a direct comparison, since it has to be from the same master. If you were to decode both the core and the full HD stream to PCM and send that PCM to your "HD Amp", I'm positive that in most cases you wouldn't even be able to tell the difference. What these devices do is cheat you by playing with volume and EQ settings that play towards how people perceive audio. Just a slight bit more volume for HD, and most people already perceive it as "better", and there is more such tricks.

Or take a HD track and re-encode it as AC3, just to ensure its the same master, and then decode both back to PCM and send that to the Amp so the Amp does not know what the original format was.

There is a lot of trickery to try to sell you on "HD" stuff, because they had to sell you something, and in fact the audio quality difference have been minimal for years. If one really goes deep into it on a technical level, you'll eventually find that out. If you just blindly trust the Amp, then sure, HD probably sounds better to you, but not because its HD audio, but because the Amp cheats you.
__________________
LAV Filters - open source ffmpeg based media splitter and decoders

Last edited by nevcairiel; 15th January 2019 at 15:51.
nevcairiel is offline   Reply With Quote
Old 15th January 2019, 16:28   #6648  |  Link
Atak_Snajpera
RipBot264 author
 
Atak_Snajpera's Avatar
 
Join Date: May 2006
Location: Poland
Posts: 7,165
Quote:
Originally Posted by nevcairiel View Post
Except on a technical level it really is not.

At least DTS has a "core" you can use for a direct comparison, since it has to be from the same master. If you were to decode both the core and the full HD stream to PCM and send that PCM to your "HD Amp", I'm positive that in most cases you wouldn't even be able to tell the difference. What these devices do is cheat you by playing with volume and EQ settings that play towards how people perceive audio. Just a slight bit more volume for HD, and most people already perceive it as "better", and there is more such tricks.

Or take a HD track and re-encode it as AC3, just to ensure its the same master, and then decode both back to PCM and send that to the Amp so the Amp does not know what the original format was.

There is a lot of trickery to try to sell you on "HD" stuff, because they had to sell you something, and in fact the audio quality difference have been minimal for years. If one really goes deep into it on a technical level, you'll eventually find that out. If you just blindly trust the Amp, then sure, HD probably sounds better to you, but not because its HD audio, but because the Amp cheats you.
That whole TrueHD/Lossless audio topic reminds of 192KHz 24bit bullshit promoted by some well known companies. (Super Audio-CD , DVD-Audio and others). Facts are simple. 48Khz 16bit is more than enough for humans. Adults have hearing range up to ~18KHz ,so it still below 24Khz. The same story with bit depth.
TrueHD can sounds better than AC3 640kbps only if was encoded from better source or your amp is doing some tricks boosting artificially volume for some frequencies. (bass/trebles). If 128kbps OPUS/AAC is transparent for 2.0 then I see no reason why 320kbps wouldn't be enough for 5.1.

Last edited by Atak_Snajpera; 15th January 2019 at 16:31.
Atak_Snajpera is online now   Reply With Quote
Old 15th January 2019, 17:10   #6649  |  Link
jd17
Registered User
 
Join Date: Jun 2017
Posts: 89
Quote:
Originally Posted by asarian View Post
Believe me, I was in the same camp as you, one day, thinking you wouldn't be able to tell the difference... until I got an actual HD Amp. The fullness of the track when you switch to HD audio is staggering -- to the point where I can barely bear to listen to AC3 any more.
I get the feeling that you do not really understand where we are coming from...
We don't doubt you hear a difference!
But that difference is not based on codec superiority, but mastering, volume, dynamic compression and so forth.

However, we are turning in circles here, it's all been said already. You either do some legwork yourself and compare apples with apples, or you keep believing.

BTW, lossless-capable AVRs have been around for at least 10 years... Do you really think you are the only person here who owns one?


Sorry for the off-topic loop, let's get back to x265.
jd17 is offline   Reply With Quote
Old 15th January 2019, 22:57   #6650  |  Link
benwaggoner
Moderator
 
Join Date: Jan 2006
Location: Portland, OR
Posts: 2,966
Quote:
Originally Posted by LigH View Post
No. I believe because GPU features would not speed x265 up. At least not without risking a loss of quality or losing the independence from hardware and software platforms (portability).

GPU features are not magical general speed-ups for every case of use, sometimes they just don't match the requirements.
I could see a 20-25% speedup for high quality encoding using GPU and fixed-function encoder features with the new, deeper Intel encoder/decoder APIs for preanalysis and such. Not because it would natively produce high quality output, but because it could help determine some optimal encoding parameters.
__________________
Ben Waggoner
Principal Video Specialist, Amazon Prime Video

My Compression Book
benwaggoner is offline   Reply With Quote
Old 15th January 2019, 23:07   #6651  |  Link
benwaggoner
Moderator
 
Join Date: Jan 2006
Location: Portland, OR
Posts: 2,966
Quote:
Originally Posted by jd17 View Post
Nobody questions that lossless - in theory, or better measurably - is always better.
I'll exactly argue against that. Information is a difference that makes a difference. A difference people can't discriminate in a proper double-blind test isn't a difference that matters.

Lossless or near lossless for sources makes sense, to the degree the extra information can eventually result in a detectable difference in derived content. Lossless, if used at all, is only used for archiving deep in studios.
__________________
Ben Waggoner
Principal Video Specialist, Amazon Prime Video

My Compression Book
benwaggoner is offline   Reply With Quote
Old 15th January 2019, 23:21   #6652  |  Link
jd17
Registered User
 
Join Date: Jun 2017
Posts: 89
I agree with you. That's why I inserted "in theory".
jd17 is offline   Reply With Quote
Old 17th January 2019, 16:37   #6653  |  Link
Selur
Registered User
 
Selur's Avatar
 
Join Date: Oct 2001
Location: Germany
Posts: 5,882
Question regarding:
Code:
--qp-adaptation-range
is this a suboption of '-aq-mode 1+', '--hevc-aq', both, or is it independent of both?

Cu Selur
__________________
Hybrid here in the forum, homepage

Last edited by Selur; 17th January 2019 at 16:44.
Selur is offline   Reply With Quote
Old 17th January 2019, 19:46   #6654  |  Link
benwaggoner
Moderator
 
Join Date: Jan 2006
Location: Portland, OR
Posts: 2,966
Quote:
Originally Posted by Selur View Post
Question regarding:
Code:
--qp-adaptation-range
is this a suboption of '-aq-mode 1+', '--hevc-aq', both, or is it independent of both?
I believe it only applies to --hevc-aq.
__________________
Ben Waggoner
Principal Video Specialist, Amazon Prime Video

My Compression Book
benwaggoner is offline   Reply With Quote
Old 22nd January 2019, 18:27   #6655  |  Link
kosta1000
Registered User
 
Join Date: Jan 2019
Posts: 1
hi guys. Where can I find changelog for x265 3.0 ???

on official site, changelog exists only for version 2.9

another question : When Ryzen 2 get out around this June, would this processor have much better performance in x265 encoding, while AMD put 256-bit AVX2 now, along with many other notable improvments.
kosta1000 is offline   Reply With Quote
Old 22nd January 2019, 19:30   #6656  |  Link
Selur
Registered User
 
Selur's Avatar
 
Join Date: Oct 2001
Location: Germany
Posts: 5,882
Quote:
hi guys. Where can I find changelog for x265 3.0 ???
Probably hasn't been written yet,... iirc there hasn't been a 3.0 final/stable flag last tag was '3.0_RC'.
__________________
Hybrid here in the forum, homepage
Selur is offline   Reply With Quote
Old 22nd January 2019, 19:49   #6657  |  Link
benwaggoner
Moderator
 
Join Date: Jan 2006
Location: Portland, OR
Posts: 2,966
Quote:
Originally Posted by Selur View Post
Probably hasn't been written yet,... iirc there hasn't been a 3.0 final/stable flag last tag was '3.0_RC'.
The best bet for the moment is to read the documentation that got added to —fullhelp in the checking.

https://bitbucket.org/multicoreware/.../branch/stable
__________________
Ben Waggoner
Principal Video Specialist, Amazon Prime Video

My Compression Book
benwaggoner is offline   Reply With Quote
Old 23rd January 2019, 17:13   #6658  |  Link
agressiv
Registered Loser
 
agressiv's Avatar
 
Join Date: Dec 2004
Posts: 110
x265 3.0 Release is out!

Looks like 3.0 is finally released! Congrats to the team! Here are the release notes:

Quote:
New features
-------------
1. option:: '--dolby-vision-profile <integer|float>' generates bitstreams confirming to the specified Dolby Vision profile. Currently profile 5, profile 8.1 and profile 8.2 enabled, Default 0 (disabled)

2. option:: '--dolby-vision-rpu' File containing Dolby Vision RPU metadata. If given, x265's Dolby Vision metadata parser will fill the RPU field of input pictures with the metadata
read from the file. The library will interleave access units with RPUs in the bitstream. Default NULL (disabled).

3. option:: '--zonefile <filename>' specifies a text file which contains the boundaries of the zones where each of zones are configurable.

4. option:: '--qp-adaptation-range' Delta-QP range by QP adaptation based on a psycho-visual model. Default 1.0.

5. option:: '--refine-ctu-distortion <0/1>' store/normalize ctu distortion in analysis-save/load. Default 0.

6. Experimental feature option:: '--hevc-aq' enables adaptive quantization
It scales the quantization step size according to the spatial activity of one coding unit relative to frame average spatial activity. This AQ method utilizes
the minimum variance of sub-unit in each coding unit to represent the coding unit’s spatial complexity.

Encoder enhancements
--------------------
1. Preset: change param defaults for veryslow and slower preset. Replace slower preset with defaults used in veryslow preset and change param defaults in veryslow preset as per experimental results.
2. AQ: change default AQ mode to auto-variance
3. Cutree offset reuse: restricted to analysis reuse-level 10 for analysis-save -> analysis-load
4. Tune: introduce --tune animation option which improves encode quality for animated content
5. Reuse CU depth for B frame and allow I, P frame to follow x265 depth decision

Bug fixes
---------
1. RC: fix rowStat computation in const-vbv
2. Dynamic-refine: fix memory reset size.
3. Fix Issue #442: linking issue on non x86 platform
4. Encoder: Do not include CLL SEI message if empty
5. Fix issue #441 build error in VMAF lib
agressiv is offline   Reply With Quote
Old 23rd January 2019, 17:35   #6659  |  Link
Selur
Registered User
 
Selur's Avatar
 
Join Date: Oct 2001
Location: Germany
Posts: 5,882
Quote:
4. option:: '--qp-adaptation-range' Delta-QP range by QP adaptation based on a psycho-visual model. Default 1.0.
6. Experimental feature option:: '--hevc-aq' enables adaptive quantization
Sadly still unkown how they are related to the normal aq-modes,..
__________________
Hybrid here in the forum, homepage
Selur is offline   Reply With Quote
Old 23rd January 2019, 21:21   #6660  |  Link
benwaggoner
Moderator
 
Join Date: Jan 2006
Location: Portland, OR
Posts: 2,966
Quote:
Originally Posted by Selur View Post
Sadly still unkown how they are related to the normal aq-modes,..
--hevc-aq overrides whatever --aq-mode is set to. I suspect that --aq-strength may get overridden itself, with --aq-adaption-range being the equivalent. Or both parameters could be used together, ala the interaction of CRF with maxrate/bufsize.
__________________
Ben Waggoner
Principal Video Specialist, Amazon Prime Video

My Compression Book
benwaggoner is offline   Reply With Quote
Reply

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 23:00.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.