def test_compare_autolevels_16bit():
# compare autolevel(16-bit) and percentile autolevel(16-bit) with p0=0.0
# and p1=1.0 should returns the same arrays
image = data.camera().astype(np.uint16) * 4
selem = disk(20)
loc_autolevel = rank.autolevel(image, selem=selem)
loc_perc_autolevel = rank.autolevel_percentile(image, selem=selem,
p0=.0, p1=1.)
assert_array_equal(loc_autolevel, loc_perc_autolevel)
def test_compare_autolevels():
# compare autolevel and percentile autolevel with p0=0.0 and p1=1.0
# should returns the same arrays
image = util.img_as_ubyte(data.camera())
selem = disk(20)
loc_autolevel = rank.autolevel(image, selem=selem)
loc_perc_autolevel = rank.autolevel_percentile(image, selem=selem,
p0=.0, p1=1.)
assert_array_equal(loc_autolevel, loc_perc_autolevel)
def test_compare_autolevels_16bit():
# compare autolevel(16-bit) and percentile autolevel(16-bit) with p0=0.0
# and p1=1.0 should returns the same arrays
image = data.camera().astype(np.uint16) * 4
selem = disk(20)
loc_autolevel = rank.autolevel(image, selem=selem)
loc_perc_autolevel = rank.autolevel_percentile(image, selem=selem,
p0=.0, p1=1.)
assert_array_equal(loc_autolevel, loc_perc_autolevel)
def test_compare_autolevels():
# compare autolevel and percentile autolevel with p0=0.0 and p1=1.0
# should returns the same arrays
image = util.img_as_ubyte(data.camera())
selem = disk(20)
loc_autolevel = rank.autolevel(image, selem=selem)
loc_perc_autolevel = rank.autolevel_percentile(image, selem=selem,
p0=.0, p1=1.)
assert_array_equal(loc_autolevel, loc_perc_autolevel)
the left part of the sky. This is due to a local maximum which is very high
comparing to the rest of the neighborhood. One can moderate this using the
percentile version of the auto-level filter which uses given percentiles (one
inferior, one superior) in place of local minimum and maximum. The example
below illustrates how the percentile parameters influence the local auto-level
result.
"""
from skimage.filter.rank import autolevel_percentile
image = data.camera()
selem = disk(20)
loc_autolevel = autolevel(image, selem=selem)
loc_perc_autolevel0 = autolevel_percentile(image, selem=selem, p0=.00, p1=1.0)
loc_perc_autolevel1 = autolevel_percentile(image, selem=selem, p0=.01, p1=.99)
loc_perc_autolevel2 = autolevel_percentile(image, selem=selem, p0=.05, p1=.95)
loc_perc_autolevel3 = autolevel_percentile(image, selem=selem, p0=.1, p1=.9)
fig, axes = plt.subplots(nrows=3, figsize=(7, 8))
ax0, ax1, ax2 = axes
plt.gray()
ax0.imshow(np.hstack((image, loc_autolevel)))
ax0.set_title('Original / auto-level')
ax1.imshow(np.hstack((loc_perc_autolevel0, loc_perc_autolevel1)),
vmin=0,
vmax=255)
ax1.set_title('Percentile auto-level 0%,1%')
the left part of the sky. This is due to a local maximum which is very high
comparing to the rest of the neighborhood. One can moderate this using the
percentile version of the auto-level filter which uses given percentiles (one
inferior, one superior) in place of local minimum and maximum. The example
below illustrates how the percentile parameters influence the local auto-level
result.
"""
from skimage.filter.rank import autolevel_percentile
image = data.camera()
selem = disk(20)
loc_autolevel = autolevel(image, selem=selem)
loc_perc_autolevel0 = autolevel_percentile(image, selem=selem, p0=.00, p1=1.0)
loc_perc_autolevel1 = autolevel_percentile(image, selem=selem, p0=.01, p1=.99)
loc_perc_autolevel2 = autolevel_percentile(image, selem=selem, p0=.05, p1=.95)
loc_perc_autolevel3 = autolevel_percentile(image, selem=selem, p0=.1, p1=.9)
fig, axes = plt.subplots(nrows=3, figsize=(7, 8))
ax0, ax1, ax2 = axes
plt.gray()
ax0.imshow(np.hstack((image, loc_autolevel)))
ax0.set_title('Original / auto-level')
ax1.imshow(
np.hstack((loc_perc_autolevel0, loc_perc_autolevel1)), vmin=0, vmax=255)
ax1.set_title('Percentile auto-level 0%,1%')
ax2.imshow(