i 0001_0250.avi

# comment
s street1.mov {
  a 2 2
  a 1 1
  x x1.mov
  x x2.mov
  v 0.8
}

s street2.mov {
  x x1.mov
  x x2.mov
  v 1.2
}

s street3.mov {
  x x1.mov
  x x2.mov
  v 0.9
}

s street4.mov {
  x x1.mov
  x x2.mov
  v 3.0
}

s street5.mov {
  x x1.mov
  x x2.mov
  v 2.9
}

s street6.mov {
  x x1.mov
  x x2.mov
  v 2.8
}

# x1.mov and x2.mov are actually simlinks to
# 0001_0250.avi [extension doesn't matter, type
# is detected by content]
x x1.mov { 
  a 50  1
  a 100 3
# exit: e center_x1 framenum1 center_x2 framenum2
  e street1.mov 800 60 600 89
  e street2.mov 1200 150 1440 179
  e street3.mov 1020 220 1020 250
}

x x2.mov { 
  e street4.mov 800 60 600 89
  e street5.mov 1200 150 1440 179
  e street6.mov 1020 220 1020 250
}