apply_chords

Adds chords to the void space in the specified direction

import matplotlib.pyplot as plt
import numpy as np
import porespy as ps
import scipy.ndimage as spim
import skimage
ps.visualization.set_mpl_style()

/opt/hostedtoolcache/Python/3.8.16/x64/lib/python3.8/site-packages/openpnm/algorithms/_invasion_percolation.py:358: NumbaDeprecationWarning: The 'nopython' keyword argument was not supplied to the 'numba.jit' decorator. The implicit default value for this argument is currently False, but it will be changed to True in Numba 0.59.0. See https://numba.readthedocs.io/en/stable/reference/deprecation.html#deprecation-of-object-mode-fall-back-behaviour-when-using-jit for details.
  def _find_trapped_pores(inv_seq, indices, indptr, outlets):  # pragma: no cover

shape

shape = [200, 200]
im = ps.generators.blobs(shape=shape, porosity=0.4)
fig, ax = plt.subplots(1, 1, figsize=[4, 4])
ax.imshow(im, origin='lower', interpolation='none')
ax.axis(False);

spacing

Separation between chords. The default is 1 voxel. This can be decreased to 0, meaning that the chords all touch each other, which automatically sets to the label argument to True

x = ps.filters.apply_chords(im=im, spacing=1)
xx = ps.filters.apply_chords(im=im, spacing=3)


fig, ax = plt.subplots(1, 2, figsize=[8, 4])
ax[0].imshow(x)
ax[1].imshow(xx)
ax[0].axis(False)
ax[1].axis(False)
ax[0].set_title('spacing = 1')
ax[1].set_title('spacing = 3');

axis

The axis along which the chords are drawn.

xx = ps.filters.apply_chords(im=im, axis=1)

fig, ax = plt.subplots(1, 2, figsize=[8, 4])
ax[0].imshow(x)
ax[1].imshow(xx)
ax[0].axis(False)
ax[1].axis(False)
ax[0].set_title('axis = 0')
ax[1].set_title('axis = 1');

trim_edges

Whether or not to remove chords that touch the edges of the image. The default is True.

xx = ps.filters.apply_chords(im=im, trim_edges=False)

fig, ax = plt.subplots(1, 2, figsize=[8, 4])
ax[0].imshow(x)
ax[1].imshow(xx)
ax[0].axis(False)
ax[1].axis(False)
ax[0].set_title('trim_edges = True')
ax[1].set_title('trim_edges = False');

label

If True the chords in the returned image are each given a unique label, such that all voxels lying on the same chord have the same value. This is automatically set to True if spacing is 0, but is False otherwise.

xx = ps.filters.apply_chords(im=im, label=True)

fig, ax = plt.subplots(1, 2, figsize=[8, 4])
ax[0].imshow(x)
ax[1].imshow(xx)
ax[0].axis(False)
ax[1].axis(False)
ax[0].set_title('label = False')
ax[1].set_title('label = True');