Source code for ddd_pylib.labeling._connected_components_labeling_operator

from ddd_pylib._base import ImageOperator
from skimage.measure import label
import xarray as xr




class ConnectedComponentsLabelingOperator(ImageOperator):
    """
    Takes an image and creates assigns a unique ID to all the voxels part of the same isolated connected component.
    The `connectivity` is to determine whether two pixels can be linked in diagonal or not.
    The possible values are:
    - 1 (only direct neighbors)
    - 2 (direct and diagonal neighbors)
    """
    def __init__(self):
        super().__init__()
        self.connectivity = self.defaultConnectivity()



    @staticmethod
    def defaultConnectivity() -> int:
        return 1




    def getPrefix(self):
        return "CCL-"




    def setConnectivity(self, connectivity):
        """
        Used to switch between direct connectivity and direct+diagonal connectivity. 
        The possible values are:
        - 1 (only direct neighbors)
        - 2 (direct and diagonal neighbors)

        Args:
            connectivity: The value of the wanted connectivity
        """
        if connectivity is None:
            raise ValueError("Connectivity can't be None")
        self.connectivity = connectivity


    def _labeling(self, image: xr.DataArray) -> xr.DataArray:
        labeled = label(image.values, connectivity=self.connectivity)
        return xr.DataArray(
            labeled,
            dims=image.dims,
            attrs=image.attrs
        )

    def _applyToFrame(self, frameData, t, nT):
        image = frameData[0]
        return self._labeling(image)