This comprehensive FFmpeg encoding comparison includes H.264 and H.265 HEVC from the fastest preset ultrafast through to veryslow with CRF values from 20 to 30.

The posts will be split up with a finale putting the fasts and slows presets from both H.264 with HEVC together.

H.265 preset crf comparison graphs

This post is part 2 of the H265 (HEVC) encoding. part 1, 2, 3 and 4 For H.264 can be found at the links. Part 1 for H265 here.

The server

Intel Xeon E-2246G CPU with 6 cores, 12 threads at 3.60GHz boosted to 4.80GHz with 32GB of ram and SSD disk running Ubuntu 18.04 64 bit.

CPU model            : Intel(R) Xeon(R) E-2246G CPU @ 3.60GHz
Number of cores      : 12
CPU frequency        : 4200.984 MHz
Total size of Disk   : 877.5 GB (25.1 GB Used)
Total amount of Mem  : 32068 MB (365 MB Used)
Total amount of Swap : 1951 MB (0 MB Used)
System uptime        : 1 days, 4 hour 47 min
Load average         : 0.00, 0.00, 1.19
OS                   : Ubuntu 18.04.3 LTS
Arch                 : x86_64 (64 Bit)
Kernel               : 4.15.0-72-generic
----------------------------------------------------------------------
I/O speed(1st run)   : 438 MB/s
I/O speed(2nd run)   : 440 MB/s
I/O speed(3rd run)   : 440 MB/s
Average I/O speed    : 439.3 MB/s

The Xeon E-2246G is a very recently released CPU (Q2 2019). FFmpeg version 3.4.6.

The source media

Thanks to jell.yfish.us the source media file for the H.265 testing is this file here. At 4k resolution (3840×2160) 29.97 fps, 30 seconds long, 400Mbps bitrate, 10 bit and a file size of 1.4GB this video file is rich in its data.

Results

Here graphs for all the presets and crf’s for H265 with encoding FPS, time taken to finish encoding, bitrate and end file size in kilobytes.

Each crf value from 20 to 30 with all the presets:

Encode time taken

End file size

Bitrate