PASS: channel planes, axis meanings, selection, alpha endpoints, scalar compositing oracle, color transfer and invalid contracts
PASS: filtering worked example; replicated borders; signed step and ramp gradients; independent scalar correlation oracle; OpenCV agreement; invalid contracts
PASS: connected-component counts, area selection, centroids and boxes; 40 independent SciPy partition checks; empty/full masks and invalid contracts
{
  "environment": {
    "python": "3.12.13",
    "numpy": "2.5.2",
    "opencv": "4.13.0",
    "scipy": "1.18.1"
  },
  "cases": {
    "exact": {
      "iou": 1.0,
      "dice": 1.0,
      "hd": 0.0,
      "hd95": 0.0
    },
    "shifted": {
      "iou": 0.7142857142857143,
      "dice": 0.8333333333333334,
      "hd": 1.0,
      "hd95": 1.0
    },
    "outlier": {
      "iou": 0.972972972972973,
      "dice": 0.9863013698630136,
      "hd": 4.242640687119285,
      "hd95": 0.0
    },
    "disjoint": {
      "iou": 0.0,
      "dice": 0.0,
      "hd": 9.899494936611665,
      "hd95": 9.253541981258827
    },
    "both-empty": {
      "iou": 1.0,
      "dice": 1.0,
      "hd": 0.0,
      "hd95": 0.0
    },
    "one-empty": {
      "iou": 0.0,
      "dice": 0.0,
      "hd": "infinity",
      "hd95": "infinity"
    }
  }
}
PASS: image/layout contracts; threshold equality; cleaning success/failure; six metric cases; symmetry; spacing; SciPy HD and 48 EDT comparisons