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             0            ..FV...... draw bars
     dot             1            ..FV...... draw dots
     line            2            ..FV...... draw lines
  slide             <int>        ..FV...... set slide mode (from 0 to 4) (default frame)
     frame           0            ..FV...... draw new frames
     replace         1            ..FV...... replace old columns with new
     scroll          2            ..FV...... scroll from right to left
     rscroll         3            ..FV...... scroll from left to right
     picture         4            ..FV...... display graph in single frame
  size              <image_size> ..FV...... set graph size (default "900x256")
  s                 <image_size> ..FV...... set graph size (default "900x256")
  rate              <video_rate> ..FV...... set video rate (default "25")
  r                 <video_rate> ..FV...... set video rate (default "25")


