/x264_tests

Primary LanguageShell

X264 Tests

Scripts to develop different tests in the X264 codec, using:

  • ffmpeg: Encoding software
  • vmaf: Objective quality video measurements

Here follows interesting experiments using a sample video input and some of the scripts avaiable in this repo.

x264 Presets: Encoding time, size and quality

Config:

  • CRF: 21
  • Profile: High (default)
  • Video length: 10s
Preset time size quality
ultrafast 1,458s 9,2M 96.68
superfast 2,230s 7,1M 95.68
veryfast 2,874s 3,9M 93.39
faster 4,220s 4,6M 95.61
fast 5,464s 5,1M 96.00
medium 6,420s 4,7M 96.30
slow 8,912s 4,5M 96.38
slower 17,096s 4,4M 96.83
veryslow 34,280s 4,1M 96.74

NOTE: Quality measured as output given by vmaf

x264 CRF: Size and quality

Config:

  • Preset: slow
  • Profile: High (default)
  • Video length: 10s
CRF size quality
17 6,9M 98.00
18 6,2M 97.68
19 5,6M 97.29
20 5,0M 96.87
21 4,5M 96.38
22 4,0M 95.68
23 3,5M 94.84
24 3,1M 93.90
25 2,7M 92.84
26 2,3M 91.63
27 2,0M 90.30
28 1,8M 88.88

NOTE: Quality measured as output given by vmaf