{
  "inside_mask_mean_absolute_rgb_difference": 0.07722670547231927,
  "outside_mask_mean_absolute_rgb_difference": 0.027705603220801157,
  "pixel_scale": "RGB 0..1; mean over channels then pixels; raw output, no compositing",
  "scope": "pixel change only, not semantic success or quality",
  "follow_up_object_mask": {
    "inside_mask_mean_absolute_rgb_difference": 0.21022012354760378,
    "outside_mask_mean_absolute_rgb_difference": 0.02900618026924703,
    "scope": "Same metric, different mask; not a quality improvement score"
  }
}