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Old 8th February 2021, 23:01   #6  |  Link
benwaggoner
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Join Date: Jan 2006
Location: Portland, OR
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[QUOTE=YaBoyShredderson;1935598]So its worth using slower over slow? Not worth going much slower than that?/QUOTE]
veryslow and placebo will give some small incremental gains at the cost of a lot of encoding time. Slower is where most of the good stuff kicks in, so quality tuning between slower-veryslow-placebo is pretty similar.

Quote:
I heard that x265 was LESS parralelizable than x264?/QUOTE]
Not in my experience, but it may vary depending on preset and other parameters. Wavefront Parallel Processing (wpp) is one useful feature for parallelism not in H.264. And x265 has features like --pmode which offer other paths to increase parallelism.

QUOTE]Would it not still make sense to use only 12 threads out 24 anyway? I can play games while encoding, and when im not playing, i can run a second encode. Does fewer threads not mean higher compression efficiency like with x264? If only marginal?/QUOTE]
Sure, if you want to do other things, sure. Fewer threads can impact quality slightly because a variety of parameters auto-adjust based on the number of available threads, but you can get the same results by manually setting those parameters. On my dual-socket workstation, I almost always pin encoding to one or the other physical CPU for this reason. It's only with 8K encoding that more than 36 logical threads wind up being more important that the NUMA overhead.

QUOTE]Yes thats what i thought, high is just another set of restraints. It wont impact quality unless i max out the main teir of whatever level im on. At first i thought it was like x264, where high is actually more efficient than main.
You're talking about High Profile in x264. The equivalent in x265 would be using Main10 or something. The key tool of High Profile in H.264 is allowing for 8x8 blocks. HEVC's Main allows for up to 32x32 blocks.

Tier is something orthgonal.

Quote:
So leaving level unrestricted is best?
Letting x265 pick for you is generally fine, unless you're doing something unusual and specific. Unrestricted is bad because you can't predict decoder compatibility. I've only ever had an unrestricted level when doing lossless encoding, since there is no way to control VBV anyway.
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