Segmentation
Average symmetric surface distance
Implemented
segmentation.average_surface_distanceDefinition
Mean distance from every boundary point of each mask to the nearest boundary point of the other, pooled over both directions.
Formula
ASSD = (Σ_{a∈∂A} d(a, ∂B) + Σ_{b∈∂B} d(b, ∂A)) / (|∂A| + |∂B|)
Range: [0, ∞)
Inputs and outputs
- y_true: ground-truth label mask
- y_pred: predicted mask with the same shape
- spacing: optional pixel spacing
Returns: MetricResult
Assumptions
No assumptions beyond valid, aligned inputs of the documented types.
Limitations
No metric-specific limitations are documented yet. Interpret the value alongside the task, data, and other metrics.
Python API
import evalsuite as es
es.average_surface_distance(mask_true, mask_pred, labels=[1])References
- Maier-Hein L, Reinke A, Godau P, et al. Metrics reloaded: recommendations for image analysis validation. Nat Methods. 2024;21(2):195-212.