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            0            ..FV.......
     color_negative  1            ..FV.......
     cross_process   2            ..FV.......
     darker          3            ..FV.......
     increase_contrast 4            ..FV.......
     lighter         5            ..FV.......
     linear_contrast 6            ..FV.......
     medium_contrast 7            ..FV.......
     negative        8            ..FV.......
     strong_contrast 9            ..FV.......
     vintage         10           ..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.

