Filter curves
  Adjust components curves.
    slice threading supported
    Inputs:
       #0: default (video)
    Outputs:
       #0: default (video)
curves AVOptions:
  preset            <int>        ..FV..... select a color curves preset (from 0 to 10) (default none)
     none                         ..FV.....
     color_negative               ..FV.....
     cross_process                ..FV.....
     darker                       ..FV.....
     increase_contrast              ..FV.....
     lighter                      ..FV.....
     linear_contrast              ..FV.....
     medium_contrast              ..FV.....
     negative                     ..FV.....
     strong_contrast              ..FV.....
     vintage                      ..FV.....
  master            <string>     ..FV..... set master points coordinates
  m                 <string>     ..FV..... set master points coordinates
  red               <string>     ..FV..... set red points coordinates
  r                 <string>     ..FV..... set red points coordinates
  green             <string>     ..FV..... set green points coordinates
  g                 <string>     ..FV..... set green points coordinates
  blue              <string>     ..FV..... set blue points coordinates
  b                 <string>     ..FV..... set blue points coordinates
  all               <string>     ..FV..... set points coordinates for all components
  psfile            <string>     ..FV..... set Photoshop curves file name
  plot              <string>     ..FV..... save Gnuplot script of the curves in specified file

This filter has support for timeline through the 'enable' option.

