{
  "image": "img_6329.jpg",
  "image_size": [
    1800,
    1350
  ],
  "wheel_trim_samples_pixels": {
    "rear": [
      [
        423.3333333333333,
        765.0
      ],
      [
        470.66666666666663,
        778.3333333333334
      ],
      [
        506.66666666666663,
        811.3333333333334
      ],
      [
        526.6666666666666,
        852.0
      ],
      [
        523.3333333333334,
        882.0
      ],
      [
        501.66666666666663,
        905.0
      ],
      [
        471.33333333333337,
        911.6666666666666
      ],
      [
        433.3333333333333,
        902.0
      ],
      [
        404.6666666666667,
        875.0
      ],
      [
        387.3333333333333,
        843.0
      ],
      [
        381.6666666666667,
        811.6666666666666
      ],
      [
        394.0,
        781.3333333333334
      ]
    ],
    "front": [
      [
        1460.0,
        864.0
      ],
      [
        1520.0,
        878.5
      ],
      [
        1560.0,
        912.0
      ],
      [
        1577.5,
        957.5
      ],
      [
        1568.5,
        1002.0
      ],
      [
        1532.5,
        1034.5
      ],
      [
        1478.5,
        1049.0
      ],
      [
        1422.5,
        1041.0
      ],
      [
        1374.5,
        1010.0
      ],
      [
        1348.5,
        966.0
      ],
      [
        1350.5,
        925.5
      ],
      [
        1385.0,
        887.0
      ]
    ]
  },
  "spindle_centers_pixels": [
    [
      455.3,
      842.7
    ],
    [
      1458.0,
      960.5
    ]
  ],
  "source": "Existing owner IMG_6329; pixel coordinates manually sampled from the unchanged1800\u00d71350 image.",
  "evidence_class": "Owner-photo estimates plus published nominal axle datums; no direct owner dimensions.",
  "construction_assumptions": {
    "trim_face_outboard_offset_mm": 67.15,
    "cap_face_outboard_offset_mm": 36,
    "axle_center_y_body_units": 0.39,
    "straight_unsteered_wheel_planes": true,
    "centered_principal_point": true,
    "square_pixels": true,
    "common_circular_trim_radius": true
  },
  "limits": "The trim is not equated to the nominal13-inch bead seat. Offset hypotheses follow the current wheel drawing, not a fitted wheel marking or survey. No lens calibration, measured tracks/offsets, steering angle or suspension load. Manual boundary samples are approximate (about3 pixels); systematic camera/model uncertainty is larger. Small fitted wheel residuals are not independent validation. Occluded body features must not constrain geometry. No hidden mount, clearance or removal path is calibrated.",
  "independent_review": "The marker remains excluded from the numerical camera fit. Under the same wheel-based camera, the shorter-front construction reduces its projected offset. The photo qualitatively informed the front-only allocation, so this is conditional corroboration, not independent fitted-dimension validation. Rear opening and screen/corner registration still need reconciliation across existing views. No measured overhang or hidden mount is established.",
  "held_out_side_marker_center_pixels": [
    1678,
    811
  ],
  "held_out_side_marker_sampling_uncertainty_pixels": 5,
  "camera_fit": {
    "camera_position_body_units": [
      -3.274554294353708,
      1.9713541782355002,
      0.9490019029167606
    ],
    "world_to_camera_rotation": [
      [
        0.31070706170591456,
        -0.06614849449227911,
        0.9482011909307442
      ],
      [
        -0.3663231410703313,
        -0.9288466206306586,
        0.055238679015443576
      ],
      [
        0.8770795164193739,
        -0.36451108627778384,
        -0.3128309285511056
      ]
    ],
    "world_to_camera_translation": [
      0.24798451965525312,
      0.579119040306917,
      3.887502096413822
    ],
    "focal_length_pixels": 1346.0769872020132,
    "estimated_trim_radius_mm": 180.7277923892184,
    "projected_spindle_centers_pixels": [
      [
        461.0281700160561,
        834.3919426738885
      ],
      [
        1459.1066645673902,
        949.4469440556975
      ]
    ],
    "center_residuals_pixels": [
      [
        5.728170016056083,
        -8.308057326111566
      ],
      [
        1.1066645673902258,
        -11.053055944302514
      ]
    ],
    "fit_parameters": [
      -2.319148172532285,
      0.3929524566982328,
      -1.6584868905541863,
      0.24798451965525312,
      0.579119040306917,
      3.887502096413822,
      7.204949705598713,
      -1.5443150815373983
    ],
    "trim_face_centers_body_units": [
      [
        -0.7543110236220472,
        0.39,
        -1.2
      ],
      [
        -0.7777485236220472,
        0.39,
        1.2
      ]
    ],
    "cap_face_centers_body_units": [
      [
        -0.71751968503937,
        0.39,
        -1.2
      ],
      [
        -0.74095718503937,
        0.39,
        1.2
      ]
    ],
    "center_residual_rms_pixels": 7.503840690596352
  },
  "held_out_side_marker_projected_pixels": [
    1702.2726928869954,
    821.0686150449642
  ],
  "held_out_side_marker_residual_pixels": [
    24.2726928869954,
    10.06861504496419
  ],
  "held_out_side_marker_current_body_units": [
    -0.78,
    0.74,
    1.5791561330414519
  ],
  "previous_drawing_marker_projected_pixels": [
    1766.23287469734,
    826.095983852048
  ],
  "previous_drawing_marker_residual_pixels": [
    88.2328746973401,
    15.095983852047993
  ],
  "camera_refit_for_front_clip_change": false
}