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 > VP9 and AV1

Reply
 
Thread Tools Search this Thread Display Modes
Old 15th October 2021, 15:21   #2421  |  Link
hajj_3
Registered User
 
Join Date: Mar 2004
Posts: 1,031
Libaom v3.2.0

This release includes compression efficiency and perceptual quality improvements, speedup and memory optimizations, as well as some new features.
- New Features
* Introduced speeds 7, 8, and 9 for all intra mode.
* Introduced speed 10 for real time mode.
* Introduced an API that allows external partition decisions.
* SVC: added support for compound prediction.
* SVC: added support for fixed SVC modes.
- Compression Efficiency Improvements
* Intra-mode search improvement.
* Improved real time (RT) mode BDrate savings by ~5% (RT speed 5)
and ~12% (RT speed 6). The improvement was measured on the video
conference set.
* Improved real time mode for nonrd path (speed 7, 8, 9): BDrate
gains of ~3-5%.
* Rate control and RD adjustments based on ML research in VP9.
Gains of ~0.5-1.0% for HD.
- Perceptual Quality Improvements
* Added a new mode --deltaq-mode=3 to improve perceptual quality
based on a differential contrast model for still images.
* Added a new mode –deltaq-mode=4 to improve perceptual quality
based on user rated cq_level data set for still images.
* Weighting of some intra mode and partition size choices to better
manage and retain texture.
- Speedup and Memory Optimizations
* Further improved 2-pass good quality encoder speed:
o Speed 2 speedup: 18%
o Speed 3 speedup: 22%
o Speed 4 speedup: 37%
o Speed 5 speedup: 30%
o Speed 6 speedup: 20%
* Optimized the real time encoder (measured on the video conference
set):
o RT speed 5 speedup: 110%
o RT speed 6 speedup: 77%
- Bug Fixes
* Issue 3069: Fix one-pass mode keyframe placement off-by-one error.
* Issue 3156: Fix a bug in av1_quantize_lp AVX2 optimization.
hajj_3 is offline   Reply With Quote
Old 20th October 2021, 19:11   #2422  |  Link
benwaggoner
Moderator
 
Join Date: Jan 2006
Location: Portland, OR
Posts: 3,954
Looks like a good point release, particularly for real-time encoding.

I do get nervous about deltaq modes based on still image research, though, as still-image algorithms generally need some tweaking for use with moving images.
__________________
Ben Waggoner
Principal Video Specialist, Amazon Prime Video

My Compression Book
benwaggoner is offline   Reply With Quote
Old 20th October 2021, 20:03   #2423  |  Link
nhw_pulsar
Registered User
 
Join Date: Apr 2017
Posts: 76
Quote:
Originally Posted by benwaggoner View Post
Looks like a good point release, particularly for real-time encoding.

I do get nervous about deltaq modes based on still image research, though, as still-image algorithms generally need some tweaking for use with moving images.
You do get nervous maybe also because inter-frame/motion prediction residuals absolutely don't look like a natural still image.

Still image research is not done for motion prediction residuals, for example my wavelet codec (NHW) puts forward neatness of (natural) images, but I don't know if it'll work as-is with inter-frame residuals which have completely different properties.-It would be challenging (for me) to know if wavelet image codecs could be effectively tuned to work well with a motion prediction scheme and its residuals-... Btw, I'm also waiting eagerly to evaluate this new version of AV1 in AVIF.

Cheers,
Raphael
nhw_pulsar is offline   Reply With Quote
Old 20th October 2021, 20:49   #2424  |  Link
rwill
Registered User
 
Join Date: Dec 2013
Posts: 90
Quote:
Originally Posted by benwaggoner View Post
Looks like a good point release, particularly for real-time encoding.

I do get nervous about deltaq modes based on still image research, though, as still-image algorithms generally need some tweaking for use with moving images.
I am getting nervous when there are quite a couple of deltaq modes to choose from and the encoder developers didn't eliminate all but the 'best overall' for me.
rwill is offline   Reply With Quote
Old 22nd October 2021, 04:24   #2425  |  Link
benwaggoner
Moderator
 
Join Date: Jan 2006
Location: Portland, OR
Posts: 3,954
Quote:
Originally Posted by rwill View Post
I am getting nervous when there are quite a couple of deltaq modes to choose from and the encoder developers didn't eliminate all but the 'best overall' for me.
Well, different modes can be better for different sorts of content. Grainy versus clean film/video versus cel animation/anime versus text/graphics, for example.

The dream is to have those auto-adapt to the content instead of having to pick the least-wrong one for an entire title.
__________________
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 11:23.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.