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 19th April 2017, 18:01   #1  |  Link
x265_Project
Registered User
 
Join Date: Jul 2013
Posts: 596
Study comparing HEVC HM, HHI HEVC, x265, H.264 JM and AOM AV1

A very interesting study...
http://iphome.hhi.de/marpe/download/...VC-PCS2016.pdf
x265_Project is offline   Reply With Quote
Old 19th April 2017, 23:25   #2  |  Link
benwaggoner
Moderator
 
Join Date: Jan 2006
Location: Portland, OR
Posts: 3,256
Quote:
Originally Posted by x265_Project View Post
Ah, nothing like the good old mean of PSNR values as our presumed high-accuracy proxy for perceptual quality! Plus turning off all psychovisual optimization, because they don't matter in the real world

It is surprising than AV1 does so badly on this, however, as the VPx series development was highly focused on PSNR for years.
__________________
Ben Waggoner
Principal Video Specialist, Amazon Prime Video

My Compression Book
benwaggoner is offline   Reply With Quote
Old 20th April 2017, 06:46   #3  |  Link
Blue_MiSfit
Derek Prestegard IRL
 
Blue_MiSfit's Avatar
 
Join Date: Nov 2003
Location: Los Angeles
Posts: 5,696
Yeah... yawn.

I get the academic value of this comparison but it's so far divorced from the real world (VP9 losing to x264... wut) that I can't place much value in it, personally.

x265 is bloody impressive - no doubt
Blue_MiSfit is offline   Reply With Quote
Old 20th April 2017, 09:50   #4  |  Link
easyfab
Registered User
 
Join Date: Jan 2002
Posts: 327
Quote:
Originally Posted by x265_Project View Post
Not exactly the same conclusion as what you can see here :
https://bitmovin.com/bitmovin-suppor...ce-open-media/

But i'm ok to say that at this moment x265 is really really good if you take the speed/quality ratio.

AV1 speed is too slow for the moment ( no optimizations )
And VP9 with the new MT option is now better than in the past, cpu usage from ~40% to 80% and x2 speed~for me , but quality/speed is not as good as x265 yet.

Last edited by easyfab; 20th April 2017 at 09:59.
easyfab is offline   Reply With Quote
Old 20th April 2017, 17:36   #5  |  Link
CSMR
Registered User
 
Join Date: Jun 2008
Posts: 11
Quote:
Originally Posted by easyfab View Post
Not exactly the same conclusion as what you can see here :
https://bitmovin.com/bitmovin-suppor...ce-open-media/

But i'm ok to say that at this moment x265 is really really good if you take the speed/quality ratio.
In this study HEVC codecs do well compared with AV1. But among HEVC codecs, the HHI solution is way ahead: "HHI HEVC encoder provides coding gain of 12.7%, while the encoding is more than 10 times faster compared to x265". Another study included the Intel Media SDK and that was way ahead.

Overall HEVC does well against other formats for free use (e.g. with the x265 codec), but blows everything away for commercial use (with HHI or Intel Media SDK).

Of course it will be great if x265 can significantly narrow the gap with the commercial encoders, or alternatively if the commercial encoders release free versions for non-commercial use.
CSMR is offline   Reply With Quote
Old 21st April 2017, 02:08   #6  |  Link
benwaggoner
Moderator
 
Join Date: Jan 2006
Location: Portland, OR
Posts: 3,256
Quote:
Originally Posted by CSMR View Post
In this study HEVC codecs do well compared with AV1. But among HEVC codecs, the HHI solution is way ahead: "HHI HEVC encoder provides coding gain of 12.7%, while the encoding is more than 10 times faster compared to x265". Another study included the Intel Media SDK and that was way ahead.

Overall HEVC does well against other formats for free use (e.g. with the x265 codec), but blows everything away for commercial use (with HHI or Intel Media SDK).

Of course it will be great if x265 can significantly narrow the gap with the commercial encoders, or alternatively if the commercial encoders release free versions for non-commercial use.
I am pretty cautious when trying to extrapolate from this kind of study. The test was only done in a particular config that isn't close to a real-world tuning. Fixed QP, no rate control! It seems like every block of every frame is identical, so no psychovisual tuning, no adaptive quant, no cu-tree, 1 sec fixed GOP, etcetera. So not particularly close to a real-world scenario. And there wasn't any subjective testing done.

Plus if you wanted to do a real placebo full test of x265, you'd include --tskip --cu-lossless --bframes 16 --subme 7. And (if --tune psnr doesn't turn them off) --psy-rd 0 --psy-rdoq 0 --aq-mode 0.

And comparing encoder speed in this whacked-out scenario is pretty meaningless. Placebo is slow by design, and not intended for any reasonable price/performance tradeoff. And turning off all threading makes it even less real-world relevant.

Moreover, PSNR in itself is the objective metric with the least correlation with subjective quality.

This is really more of an Excel comparison of a highly artificial scenario than actionable info. I'm not going to care much about a suggested video quality difference without seeing some video in a relevant scenario.

But such is the way of academic codec research. They do it this way because they've always done it this way.
__________________
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 06:06.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.