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          ],
          "valid": true,
          "visibility": "illustrative visible joint"
        },
        {
          "name": "image-left hip",
          "xy": [
            173,
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          ],
          "valid": true,
          "visibility": "illustrative visible joint"
        },
        {
          "name": "image-right hip",
          "xy": [
            210,
            643
          ],
          "valid": true,
          "visibility": "illustrative visible joint"
        },
        {
          "name": "image-left knee",
          "xy": [
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          ],
          "valid": true,
          "visibility": "illustrative visible joint"
        },
        {
          "name": "image-right knee",
          "xy": [
            201,
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          ],
          "valid": true,
          "visibility": "illustrative visible joint"
        },
        {
          "name": "image-left ankle",
          "xy": [
            176,
            780
          ],
          "valid": true,
          "visibility": "illustrative visible joint"
        },
        {
          "name": "image-right ankle",
          "xy": [
            199,
            786
          ],
          "valid": true,
          "visibility": "illustrative visible joint"
        }
      ],
      "edges": [
        [
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        ],
        [
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        ],
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      ],
      "source_type": "illustrative",
      "joint_side_convention": "Left/right refer to image side in this authored teaching example, not anatomical side.",
      "provenance": "Authored visible joint locations on campus-street; not measured pose estimation."
    },
    "depth": {
      "path": "figures/depth-ordering.svg",
      "source_type": "illustrative",
      "units": null,
      "meaning": "Authored ordinal layers, darker near / lighter far; no metric prediction.",
      "sky_valid": false,
      "layers": [
        {
          "region": "road",
          "shade": "#828A82"
        },
        {
          "region": "car",
          "shade": "#B9BDB7"
        },
        {
          "region": "man",
          "shade": "#555D55"
        },
        {
          "region": "woman",
          "shade": "#AEB5AA"
        },
        {
          "region": "rider",
          "shade": "#A0A99D"
        },
        {
          "region": "dog",
          "shade": "#757F70"
        }
      ],
      "provenance": "Authored ordinal layers on campus-street; not measured or metric depth."
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  },
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    {
      "id": "dog",
      "positive_point": [
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      "negative_point": [
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      "box_xyxy": [
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        1305,
        869
      ],
      "mask_path": "figures/masks/dog.svg",
      "source_type": "illustrative",
      "object_id": "dog",
      "provenance": "Authored spatial prompt and corresponding stored illustrative mask.",
      "stored_as": "precomputed"
    },
    {
      "id": "man",
      "positive_point": [
        190,
        640
      ],
      "negative_point": [
        1030,
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      ],
      "box_xyxy": [
        136,
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        244,
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      "mask_path": "figures/masks/man.svg",
      "source_type": "illustrative",
      "object_id": "man",
      "provenance": "Authored spatial prompt and corresponding stored illustrative mask.",
      "stored_as": "precomputed"
    },
    {
      "id": "woman",
      "positive_point": [
        1409,
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      "negative_point": [
        1030,
        780
      ],
      "box_xyxy": [
        1370,
        528,
        1449,
        719
      ],
      "mask_path": "figures/masks/woman.svg",
      "source_type": "illustrative",
      "object_id": "woman",
      "provenance": "Authored spatial prompt and corresponding stored illustrative mask.",
      "stored_as": "precomputed"
    },
    {
      "id": "rider",
      "positive_point": [
        961,
        615
      ],
      "negative_point": [
        1030,
        780
      ],
      "box_xyxy": [
        919,
        519,
        1004,
        711
      ],
      "mask_path": "figures/masks/rider.svg",
      "source_type": "illustrative",
      "object_id": "rider",
      "provenance": "Authored spatial prompt and corresponding stored illustrative mask.",
      "stored_as": "precomputed"
    },
    {
      "id": "car",
      "positive_point": [
        576,
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      ],
      "negative_point": [
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      ],
      "box_xyxy": [
        491,
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      ],
      "mask_path": "figures/masks/car.svg",
      "source_type": "illustrative",
      "object_id": "car",
      "provenance": "Authored spatial prompt and corresponding stored illustrative mask.",
      "stored_as": "precomputed"
    }
  ],
  "grounding_demos": [
    {
      "text": "the dog",
      "object_id": "dog",
      "box_xyxy": [
        1082,
        701,
        1305,
        869
      ],
      "mask_path": "figures/masks/dog.svg",
      "source_type": "illustrative",
      "stored_as": "precomputed",
      "provenance": "Preset phrase associated with an authored region. This is a stored demonstration, not a measured grounding prediction."
    },
    {
      "text": "the cyclist",
      "object_id": "rider",
      "box_xyxy": [
        919,
        519,
        1004,
        711
      ],
      "mask_path": "figures/masks/rider.svg",
      "source_type": "illustrative",
      "stored_as": "precomputed",
      "provenance": "Preset phrase associated with an authored region. This is a stored demonstration, not a measured grounding prediction."
    },
    {
      "text": "the person on the left",
      "object_id": "man",
      "box_xyxy": [
        136,
        480,
        244,
        801
      ],
      "mask_path": "figures/masks/man.svg",
      "source_type": "illustrative",
      "stored_as": "precomputed",
      "provenance": "Preset phrase associated with an authored region. This is a stored demonstration, not a measured grounding prediction."
    },
    {
      "text": "the vehicle in the center",
      "object_id": "car",
      "box_xyxy": [
        491,
        552,
        661,
        687
      ],
      "mask_path": "figures/masks/car.svg",
      "source_type": "illustrative",
      "stored_as": "precomputed",
      "provenance": "Preset phrase associated with an authored region. This is a stored demonstration, not a measured grounding prediction."
    },
    {
      "text": "the dog beside the cyclist",
      "object_id": "dog",
      "box_xyxy": [
        1082,
        701,
        1305,
        869
      ],
      "mask_path": "figures/masks/dog.svg",
      "source_type": "illustrative",
      "stored_as": "precomputed",
      "provenance": "Preset phrase associated with an authored region. This is a stored demonstration, not a measured grounding prediction."
    }
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    "width": 4,
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    "source_type": "illustrative"
  },
  "limitations": [
    "No segmentation or grounding model is loaded.",
    "Point and box interactions retrieve compatible stored masks.",
    "Preset phrases do not demonstrate language understanding or relational reasoning.",
    "Overlays are approximate selected-region illustrations."
  ]
}