#5854: H.264 encoding - veryfast preset produces smaller file than faster preset
-------------------------------------+-------------------------------------
             Reporter:  mimac        |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:               |                  Version:
  undetermined                       |  unspecified
             Keywords:  H.264        |               Blocked By:
  preset                             |  Reproduced by developer:  0
             Blocking:               |
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 '''Summary of the bug:'''
 According to [https://trac.ffmpeg.org/wiki/Encode/H.264], for constant
 quality encoding, faster preset should be slower and produce smaller file
 than veryfast preset. However, by my testing, faster preset produced
 always bigger file than veryfast preset.

 '''How to reproduce:'''
 {{{
 ffmpeg version N-81696-gd38dff8e-static http://johnvansickle.com/ffmpeg/
 Copyright (c) 2000-2016 the FFmpeg developers
   built with gcc 5.4.1 (Debian 5.4.1-2) 20160904
   configuration: --enable-gpl --enable-version3 --enable-static --disable-
 debug --enable-libmp3lame --enable-libx264 --enable-libx265 --enable-
 libwebp --enable-libspeex --enable-libvorbis --enable-libvpx --enable-
 libfreetype --enable-fontconfig --enable-libxvid --enable-libopencore-
 amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvo-
 amrwbenc --enable-gray --enable-libopenjpeg --enable-libopus --enable-
 libass --enable-gnutls --enable-libvidstab --enable-libsoxr --enable-
 frei0r --enable-libfribidi --disable-indev=sndio --disable-outdev=sndio
 --enable-librtmp --enable-libmfx --enable-libzimg --cc=gcc-5
   libavutil      55. 29.100 / 55. 29.100
   libavcodec     57. 57.100 / 57. 57.100
   libavformat    57. 49.100 / 57. 49.100
   libavdevice    57.  0.102 / 57.  0.102
   libavfilter     6. 62.100 /  6. 62.100
   libswscale      4.  1.100 /  4.  1.100
   libswresample   2.  1.100 /  2.  1.100
   libpostproc    54.  0.100 / 54.  0.100


 % ffmpeg  -i newmobcal1920_12mbps.ts  -c:v libx264 -profile:v high -level
 4.0 -preset faster result-faster.mkv
 % ffmpeg  -i newmobcal1920_12mbps.ts  -c:v libx264 -profile:v high -level
 4.0 -preset veryfast result-veryfast.mkv
 % ll *.mkv
 -rw-rw-r-- 1 user user 84785654 Sep 19 21:28 result-faster.mkv
 -rw-rw-r-- 1 user user 77822551 Sep 19 21:15 result-veryfast.mkv
 }}}
 Input video is from [http://www.w6rz.net]
 ([http://www.w6rz.net/newmobcal1920_12mbps.ts]). Reports are attached.

 I was able to reproduce this behavior on Ubuntu as well as Windows, with
 three different input files (H.264, MPEG2, MJPEG), also with CFR values
 18, 23 and 28. Veryfast preset always produced smaller file than faster
 and fast preset, in most cases also smaller than medium preset.

--
Ticket URL: <https://trac.ffmpeg.org/ticket/5854>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker
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