Page 1 of 1

Very slow HEVC encoding on I7700K

Posted: Thu Jul 19, 2018 8:43 am
by omeckron
Hey,

I've tried encoding numerous BR 10Bit files (MKVs) using the following:
H265 10 Bit
Avg Bitrate 15500KB (Single pass) VBR
Encoder tune - none
Encoder Profile - High
Encoder lvl - 4.1
Audio - pass-through
No Filters

I keep on getting very poor results 0 starts off somewhere @ 12FPS but averages very quickly to 4FPS~ (roughly the same i got from my very old 2012 Macbook Pro)
This led me to believe there's an issue.

Tried installing MB drivers/chipset/GPU
Tried disabling Intel speed step in the bios (thought maybe there's an issue between the scheduler and the CPU reporting the wrong frequency).
Reinstalling Handbrake.
Also tried installing codec packs etc. though I think (correct me if I'm wrong) Handbrake uses it's own codec pack.

Nothing works.

Looking at benchmarks online I should be getting somewhere around 22FPS.

Any ideas?

Thanks!

Re: Very slow HEVC encoding on I7700K

Posted: Thu Jul 19, 2018 9:33 am
by rollin_eng
Could you please post your HB logs, instructions can be found here:

https://handbrake.fr/docs/en/latest/hel ... y-log.html

Re: Very slow HEVC encoding on I7700K

Posted: Thu Jul 19, 2018 2:59 pm
by omeckron
Sure, sorry about that, here's one instance:
https://expirebox.com/download/08209939 ... d1c84.html

Re: Very slow HEVC encoding on I7700K

Posted: Thu Jul 19, 2018 3:11 pm
by mduell
Do note HB has a 8 bit video pipeline, so your 10 bit input is being downsampled to 8 bits before encoding at 10 bits. Nothing can recover those bits.

Re: Very slow HEVC encoding on I7700K

Posted: Thu Jul 19, 2018 4:29 pm
by omeckron
So why have the 10bit output in the first place?

Also, forgot to mention, I tried using 8bit output and I still get the same fps.

Thanks for your time and help! Appreciate it.

Re: Very slow HEVC encoding on I7700K

Posted: Thu Jul 19, 2018 4:38 pm
by mduell
omeckron wrote: Thu Jul 19, 2018 4:29 pmSo why have the 10bit output in the first place?
epeen mostly, it seems.

Re: Very slow HEVC encoding on I7700K

Posted: Sat Jul 21, 2018 12:32 am
by BradleyS
John is working on a pipeline overhaul to support higher bit depth internally. Encoder support is just one step toward a full solution, and happened to be the easiest to accomplish at the time.