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# medpy.metric.binary.hd¶

medpy.metric.binary.hd(result, reference, voxelspacing=None, connectivity=1)[source]

Hausdorff Distance.

Computes the (symmetric) Hausdorff Distance (HD) between the binary objects in two images. It is defined as the maximum surface distance between the objects.

Parameters: result : array_like Input data containing objects. Can be any type but will be converted into binary: background where 0, object everywhere else. reference : array_like Input data containing objects. Can be any type but will be converted into binary: background where 0, object everywhere else. voxelspacing : float or sequence of floats, optional The voxelspacing in a distance unit i.e. spacing of elements along each dimension. If a sequence, must be of length equal to the input rank; if a single number, this is used for all axes. If not specified, a grid spacing of unity is implied. connectivity : int The neighbourhood/connectivity considered when determining the surface of the binary objects. This value is passed to scipy.ndimage.morphology.generate_binary_structure and should usually be $$> 1$$. Note that the connectivity influences the result in the case of the Hausdorff distance. hd : float The symmetric Hausdorff Distance between the object(s) in result and the object(s) in reference. The distance unit is the same as for the spacing of elements along each dimension, which is usually given in mm.