{
  "units": "mixed_measured_and_normalized_values",
  "mueller_matrix": {
    "nominal_range": [-1, 1],
    "stored_values": "measured_or_processed_float32_values_not_forcibly_clipped",
    "note": "Real measured Mueller matrix elements may slightly exceed the nominal [-1, 1] range because of acquisition noise, calibration differences, numerical processing, or normalization error. Users should inspect distributions and apply task-appropriate clipping, standardization, or normalization before training."
  },
  "parameters": {
    "D": {
      "range": [0, 1],
      "description": "Diattenuation-related target modality."
    },
    "Delta": {
      "range": [0, 1],
      "description": "Depolarization-related target modality."
    },
    "eta": {
      "range": [0, "pi"],
      "description": "Retardance-related target modality."
    },
    "theta": {
      "range": ["-pi/2", "pi/2"],
      "description": "Orientation-related target modality."
    },
    "psi": {
      "range": ["-pi/2", "pi/2"],
      "description": "Orientation-related target modality."
    },
    "R": {
      "range": [0, "pi"],
      "description": "Retardance-related target modality."
    }
  },
  "normalization": {
    "mueller": "not_forcibly_clipped_to_nominal_range",
    "waveplate_targets": "stored_from_source_npy_as_float32",
    "spectral_targets": "converted_from_grayscale_png_uint8_to_float32_divided_by_255",
    "recommendation": "Use training-set statistics or physically motivated clipping/normalization according to the downstream protocol."
  },
  "grayscale_to_physical_mapping": {
    "applies_to_target_encoding": "png_uint8_normalized_to_float32_0_1",
    "channel_order": ["D", "Delta", "eta", "theta", "psi", "R"],
    "formula": {
      "D": "D_gray",
      "Delta": "Delta_gray",
      "eta": "pi * eta_gray",
      "theta": "pi * (theta_gray - 0.5)",
      "psi": "pi * (psi_gray - 0.5)",
      "R": "pi * R_gray"
    },
    "warning": "Apply this mapping only to normalized grayscale target tensors. Do not apply it to target tensors that are already stored in physical units."
  }
}