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Old 24th September 2019, 20:37   #50  |  Link
benwaggoner
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Join Date: Jan 2006
Location: Portland, OR
Posts: 4,750
Quote:
Originally Posted by redbtn View Post
I don't wanna start new topic for small question, so I decided ask for help here.
I'm encoding 4k HDR > 1080p HDR with preset Slower, CRF 12-13 with output bitrate 16-17mbps. And my question is how much --merange and --ctu affects to quality?

For example:

--ctu 64 --merange 57 (2.5fps)
--ctu 32 --merange 26 (2.83fps) +13% speed
I'd get nervous about having a small merange when working at 4K resolution, but that would be content dependent. Visual comparison is probably required here.

And most 4K content can wind up using 64x64 CTUs. It's probably a bigger deal at lower bitrates.
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