labels2listsOfPoints

tomni.transformers.labels2listsOfPoints(labels: numpy.ndarray) → numpy.ndarray

Convert labeled regions into lists of points.

Parameters

labels (np.ndarray) – An array where every pixel is labeled to indicate which object it belongs to. The labels should be non-negative integers.

Returns

A list of lists, where each inner list contains the (x, y) coordinates

of points belonging to the corresponding label. The list is organized such that output[label] contains the points for the label with value label. The label values must start from 0 and be contiguous integers.

Return type

List[List[Tuple[int, int]]]

Raises

ValueError – If the number of labels exceeds the supported limit.

Note

• The function automatically determines the appropriate data type for labels based on their maximum value.

• It uses sparse matrix operations to efficiently extract points for each label.