Filter adrawgraph
  Draw a graph using input audio metadata.
    Inputs:
       #0: default (audio)
    Outputs:
       #0: default (video)
adrawgraph AVOptions:
  m1                <string>     ..FV.... set 1st metadata key (default "")
  fg1               <string>     ..FV.... set 1st foreground color expression (default "0xffff0000")
  m2                <string>     ..FV.... set 2nd metadata key (default "")
  fg2               <string>     ..FV.... set 2nd foreground color expression (default "0xff00ff00")
  m3                <string>     ..FV.... set 3rd metadata key (default "")
  fg3               <string>     ..FV.... set 3rd foreground color expression (default "0xffff00ff")
  m4                <string>     ..FV.... set 4th metadata key (default "")
  fg4               <string>     ..FV.... set 4th foreground color expression (default "0xffffff00")
  bg                <color>      ..FV.... set background color (default "white")
  min               <float>      ..FV.... set minimal value (from INT_MIN to INT_MAX) (default -1)
  max               <float>      ..FV.... set maximal value (from INT_MIN to INT_MAX) (default 1)
  mode              <int>        ..FV.... set graph mode (from 0 to 2) (default line)
     bar                          ..FV.... draw bars
     dot                          ..FV.... draw dots
     line                         ..FV.... draw lines
  slide             <int>        ..FV.... set slide mode (from 0 to 4) (default frame)
     frame                        ..FV.... draw new frames
     replace                      ..FV.... replace old columns with new
     scroll                       ..FV.... scroll from right to left
     rscroll                      ..FV.... scroll from left to right
     picture                      ..FV.... display graph in single frame
  size              <image_size> ..FV.... set graph size (default "900x256")
  s                 <image_size> ..FV.... set graph size (default "900x256")


