{
  "version": 2,
  "native_size": [
    5196,
    4018
  ],
  "source_sha256": "f7d0a02721d1109665d90af66aa4002467a4a5269a6e97cf33d8d9188e20ecae",
  "selected_pixels": 503324,
  "coverage": 0.024108409769585747,
  "exclusion_pixels": 1338900,
  "exclusion_coverage": 0.06413115575752072,
  "baseline_pixels": 221914,
  "added_pixels": 281410,
  "removed_baseline_in_protected_photographic_regions": 0,
  "dark_stroke_pixels": 53578,
  "noise_normalized": 0.007665756225389178,
  "strong_threshold_normalized": 0.030663024901556712,
  "weak_threshold_normalized": 0.015331512450778356,
  "regions_fractional_xyxy": [
    [
      0.022,
      0.035,
      0.161,
      0.977
    ],
    [
      0.255,
      0.23,
      0.66,
      0.67
    ],
    [
      0.86,
      0.72,
      0.97,
      0.95
    ],
    [
      0.91,
      0.46,
      0.982,
      0.64
    ]
  ],
  "dark_regions_fractional_xyxy": [
    [
      0.86,
      0.72,
      0.98,
      0.96
    ],
    [
      0.91,
      0.46,
      0.984,
      0.65
    ]
  ],
  "protected_photographic_boxes_fractional_xyxy": [],
  "protected_pixels_excluded": 0,
  "polarity_components": {
    "bright": 3281,
    "dark": 154
  },
  "catalog_positions_near_exclusion": 45,
  "exclusion_padding_native_pixels": 3,
  "method": "Both-polarity local contrast; contextual short and round fragments; expanded inspected regions; explicit photographic exclusions; 3-pixel padding for separate exclusion mask",
  "annotation_png": "White contrast-rendered stencil of observed bright and dark marks. annotations-observed.png preserves stretched observed pixel appearance.",
  "limitations": "Higher-recall inspected candidate mask, not semantic ground truth. Compact astronomical images in writing neighborhoods, scratches and overlapping signal remain ambiguous. Exclusion padding is a safety margin, not recovered ink. No hidden sky is reconstructed."
}