{
    "classes": [
        "plane",
        "baseball-diamond",
        "bridge",
        "ground-track-field",
        "small-vehicle",
        "large-vehicle",
        "ship",
        "tennis-court",
        "basketball-court",
        "storage-tank",
        "soccer-ball-field",
        "roundabout",
        "harbor",
        "swimming-pool",
        "helicopter"
  ]
}