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Ischemia24 · 31st July 2019, 17:54

So I have made a few changes to my baseline settings and I feel as though the quality retained at the restrained bitrates I'm using has really leveled up! Thank you Excellentswordfight for the suggestion of using no-sao and deblock -1:-1.

I came across a post claiming that H.264 changes to these settings when tuning for Film (which is what I need most of the time)

deblock=-1:-1
psy-rd=1.0:0.15

So now my default settings look like this.
rc-lookahead=120:bframes=12:ref=6:subme=7:deblock=-1:-1: psy-rd=1.0:0.15:no-sao

I should do some additional testing to find out how I feel about the subjective quality of CRF at values that result in similar bitrates to what I am specifying. I recently had a problematic 480p encode that ended up looking great just changing to CRF 22 (the video bitrate went up ~40% though).

I looked into VMAF and while I appreciate that it exists I decided I would rather subjectively evaluate my encodes.

Are there any other settings I should consider applying to improve the quality to file size ratio? I understand that some settings could be adjusted for better encoding performance in different situations with no noticeable quality loss, and feel free to chime in about that if you'd like, but I would like to get the highest quality to size ratio possible within the scope of the H.265 settings.

How would you approach dealing with a particularly grainy source?

Any thoughts on the usage of the frame-threads setting? A higher number seems like it would increase CPU utilization, but my understanding is that it would go against my goals (and that if I want to be even more ridiculous, I should use frame-threads=1), so I decided I should leave it at the default.

31st July 2019, 17:54	#18 \| Link
Ischemia24 Registered User Join Date: Nov 2016 Posts: 11	So I have made a few changes to my baseline settings and I feel as though the quality retained at the restrained bitrates I'm using has really leveled up! Thank you Excellentswordfight for the suggestion of using no-sao and deblock -1:-1. I came across a post claiming that H.264 changes to these settings when tuning for Film (which is what I need most of the time) deblock=-1:-1 psy-rd=1.0:0.15 So now my default settings look like this. rc-lookahead=120:bframes=12:ref=6:subme=7:deblock=-1:-1: psy-rd=1.0:0.15:no-sao I should do some additional testing to find out how I feel about the subjective quality of CRF at values that result in similar bitrates to what I am specifying. I recently had a problematic 480p encode that ended up looking great just changing to CRF 22 (the video bitrate went up ~40% though). I looked into VMAF and while I appreciate that it exists I decided I would rather subjectively evaluate my encodes. Are there any other settings I should consider applying to improve the quality to file size ratio? I understand that some settings could be adjusted for better encoding performance in different situations with no noticeable quality loss, and feel free to chime in about that if you'd like, but I would like to get the highest quality to size ratio possible within the scope of the H.265 settings. How would you approach dealing with a particularly grainy source? Any thoughts on the usage of the frame-threads setting? A higher number seems like it would increase CPU utilization, but my understanding is that it would go against my goals (and that if I want to be even more ridiculous, I should use frame-threads=1), so I decided I should leave it at the default.