def main():
"""Load image, apply histogram stretching and cumulative histogram
equalization. Plot the results."""
img = data.text()
height, width = img.shape
nb_pixels = height * width
# apply histogram stretching
gray_min = np.min(img)
gray_max = np.max(img)
img_hist_stretched = (img - gray_min) * (255 / (gray_max - gray_min))
img_hist_stretched = img_hist_stretched.astype(np.uint8)
# apply cumulative histogram equalization
img_cumulative = np.zeros(img.shape, dtype=np.uint8)
hist_cumulative = [0] * 256
running_sum = 0
hist, edges = np.histogram(img, 256, (0, 255))
for i in range(256):
count = hist[i]
running_sum += count
hist_cumulative[i] = running_sum / nb_pixels
for i in range(256):
img_cumulative[img == i] = int(256 * hist_cumulative[i])
# plot
plot_images_grayscale([img, img_hist_stretched, img_cumulative], [
"Image", "Histogram stretched to 0-255",
"Cumulative Histogram Equalization"
])
def test_RGB(dtype):
img = gaussian(data.text(), 1)
imgR = np.zeros((img.shape[0], img.shape[1], 3), dtype=dtype)
imgG = np.zeros((img.shape[0], img.shape[1], 3), dtype=dtype)
imgRGB = np.zeros((img.shape[0], img.shape[1], 3), dtype=dtype)
imgR[:, :, 0] = img
imgG[:, :, 1] = img
imgRGB[:, :, :] = img[:, :, None]
r = np.linspace(136, 50, 100)
c = np.linspace(5, 424, 100)
init = np.array([r, c]).T
snake = active_contour(imgR, init, boundary_condition='fixed',
alpha=0.1, beta=1.0, w_line=-5, w_edge=0, gamma=0.1)
float_dtype = _supported_float_type(dtype)
assert snake.dtype == float_dtype
refr = [136, 135, 134, 133, 132, 131, 129, 128, 127, 125]
refc = [5, 9, 13, 17, 21, 25, 30, 34, 38, 42]
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refr)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refc)
snake = active_contour(imgG, init, boundary_condition='fixed',
alpha=0.1, beta=1.0, w_line=-5, w_edge=0, gamma=0.1)
assert snake.dtype == float_dtype
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refr)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refc)
snake = active_contour(imgRGB, init, boundary_condition='fixed',
alpha=0.1, beta=1.0, w_line=-5/3., w_edge=0,
gamma=0.1)
assert snake.dtype == float_dtype
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refr)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refc)
def test_RGB():
img = gaussian(data.text(), 1)
imgR = np.zeros((img.shape[0], img.shape[1], 3))
imgG = np.zeros((img.shape[0], img.shape[1], 3))
imgRGB = np.zeros((img.shape[0], img.shape[1], 3))
imgR[:, :, 0] = img
imgG[:, :, 1] = img
imgRGB[:, :, :] = img[:, :, None]
x = np.linspace(5, 424, 100)
y = np.linspace(136, 50, 100)
init = np.array([x, y]).T
snake = active_contour(imgR, init, bc='fixed',
alpha=0.1, beta=1.0, w_line=-5, w_edge=0, gamma=0.1)
refx = [5, 9, 13, 17, 21, 25, 30, 34, 38, 42]
refy = [136, 135, 134, 133, 132, 131, 129, 128, 127, 125]
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refx)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refy)
snake = active_contour(imgG, init, bc='fixed',
alpha=0.1, beta=1.0, w_line=-5, w_edge=0, gamma=0.1)
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refx)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refy)
snake = active_contour(imgRGB, init, bc='fixed',
alpha=0.1, beta=1.0, w_line=-5/3., w_edge=0, gamma=0.1)
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refx)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refy)
def main():
"""Load image, apply histogram stretching and cumulative histogram
equalization. Plot the results."""
img = data.text()
height, width = img.shape
nb_pixels = height * width
# apply histogram stretching
gray_min = np.min(img)
gray_max = np.max(img)
img_hist_stretched = (img - gray_min) * (255 / (gray_max - gray_min))
img_hist_stretched = img_hist_stretched.astype(np.uint8)
# apply cumulative histogram equalization
img_cumulative = np.zeros(img.shape, dtype=np.uint8)
hist_cumulative = [0] * 256
running_sum = 0
hist, edges = np.histogram(img, 256, (0, 255))
for i in range(256):
count = hist[i]
running_sum += count
hist_cumulative[i] = running_sum / nb_pixels
for i in range(256):
img_cumulative[img == i] = int(256 * hist_cumulative[i])
# plot
plot_images_grayscale(
[img, img_hist_stretched, img_cumulative],
["Image", "Histogram stretched to 0-255", "Cumulative Histogram Equalization"]
)
def test_RGB():
img = gaussian(data.text(), 1)
imgR = np.zeros((img.shape[0], img.shape[1], 3))
imgG = np.zeros((img.shape[0], img.shape[1], 3))
imgRGB = np.zeros((img.shape[0], img.shape[1], 3))
imgR[:, :, 0] = img
imgG[:, :, 1] = img
imgRGB[:, :, :] = img[:, :, None]
x = np.linspace(5, 424, 100)
y = np.linspace(136, 50, 100)
init = np.array([x, y]).T
snake = active_contour(imgR, init, bc='fixed',
alpha=0.1, beta=1.0, w_line=-5, w_edge=0, gamma=0.1)
refx = [5, 9, 13, 17, 21, 25, 30, 34, 38, 42]
refy = [136, 135, 134, 133, 132, 131, 129, 128, 127, 125]
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refx)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refy)
snake = active_contour(imgG, init, bc='fixed',
alpha=0.1, beta=1.0, w_line=-5, w_edge=0, gamma=0.1)
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refx)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refy)
snake = active_contour(imgRGB, init, bc='fixed',
alpha=0.1, beta=1.0, w_line=-5/3., w_edge=0, gamma=0.1)
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refx)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refy)
def test_free_reference():
img = data.text()
x = np.linspace(5, 424, 100)
y = np.linspace(70, 40, 100)
init = np.array([x, y]).T
snake = active_contour(gaussian(img, 3), init, bc='free',
alpha=0.1, beta=1.0, w_line=-5, w_edge=0, gamma=0.1)
refx = [10, 13, 16, 19, 23, 26, 29, 32, 36, 39]
refy = [76, 76, 75, 74, 73, 72, 71, 70, 69, 69]
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refx)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refy)
def test_fixed_reference():
img = data.text()
x = np.linspace(5, 424, 100)
y = np.linspace(136, 50, 100)
init = np.array([x, y]).T
snake = active_contour(gaussian(img, 1), init, bc='fixed',
alpha=0.1, beta=1.0, w_line=-5, w_edge=0, gamma=0.1)
refx = [5, 9, 13, 17, 21, 25, 30, 34, 38, 42]
refy = [136, 135, 134, 133, 132, 131, 129, 128, 127, 125]
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refx)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refy)
def test_free_reference():
img = data.text()
x = np.linspace(5, 424, 100)
y = np.linspace(70, 40, 100)
init = np.array([x, y]).T
snake = active_contour(gaussian(img, 3), init, bc='free',
alpha=0.1, beta=1.0, w_line=-5, w_edge=0, gamma=0.1)
refx = [10, 13, 16, 19, 23, 26, 29, 32, 36, 39]
refy = [76, 76, 75, 74, 73, 72, 71, 70, 69, 69]
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refx)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refy)
def test_fixed_reference():
img = data.text()
x = np.linspace(5, 424, 100)
y = np.linspace(136, 50, 100)
init = np.array([x, y]).T
snake = active_contour(gaussian(img, 1), init, bc='fixed',
alpha=0.1, beta=1.0, w_line=-5, w_edge=0, gamma=0.1)
refx = [5, 9, 13, 17, 21, 25, 30, 34, 38, 42]
refy = [136, 135, 134, 133, 132, 131, 129, 128, 127, 125]
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refx)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refy)
def test_triangle_float_images():
text = data.text()
int_bins = text.max() - text.min() + 1
# Set nbins to match the uint case and threshold as float.
assert(round(threshold_triangle(
text.astype(np.float), nbins=int_bins)) == 104)
# Check that rescaling image to floats in unit interval is equivalent.
assert(round(threshold_triangle(text / 255., nbins=int_bins) * 255) == 104)
# Repeat for inverted image.
assert(round(threshold_triangle(
np.invert(text).astype(np.float), nbins=int_bins)) == 151)
assert (round(threshold_triangle(
np.invert(text) / 255., nbins=int_bins) * 255) == 151)
def test_free_reference(dtype):
img = data.text()
r = np.linspace(70, 40, 100)
c = np.linspace(5, 424, 100)
init = np.array([r, c]).T
img_smooth = gaussian(img, 3).astype(dtype, copy=False)
snake = active_contour(img_smooth, init, boundary_condition='free',
alpha=0.1, beta=1.0, w_line=-5, w_edge=0, gamma=0.1)
assert snake.dtype == _supported_float_type(dtype)
refr = [76, 76, 75, 74, 73, 72, 71, 70, 69, 69]
refc = [10, 13, 16, 19, 23, 26, 29, 32, 36, 39]
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refr)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refc)
def test_fixed_reference(dtype):
img = data.text()
r = np.linspace(136, 50, 100)
c = np.linspace(5, 424, 100)
init = np.array([r, c]).T
image_smooth = gaussian(img, 1).astype(dtype, copy=False)
snake = active_contour(image_smooth, init, boundary_condition='fixed',
alpha=0.1, beta=1.0, w_line=-5, w_edge=0, gamma=0.1)
assert snake.dtype == _supported_float_type(dtype)
refr = [136, 135, 134, 133, 132, 131, 129, 128, 127, 125]
refc = [5, 9, 13, 17, 21, 25, 30, 34, 38, 42]
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refr)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refc)
def test_triangle_float_images():
text = data.text()
int_bins = text.max() - text.min() + 1
# Set nbins to match the uint case and threshold as float.
assert(round(threshold_triangle(
text.astype(np.float), nbins=int_bins)) == 104)
# Check that rescaling image to floats in unit interval is equivalent.
assert(round(threshold_triangle(text / 255., nbins=int_bins) * 255) == 104)
# Repeat for inverted image.
assert(round(threshold_triangle(
np.invert(text).astype(np.float), nbins=int_bins)) == 151)
assert (round(threshold_triangle(
np.invert(text) / 255., nbins=int_bins) * 255) == 151)
def active_contour_example():
img = data.astronaut()
img = rgb2gray(img)
s = np.linspace(0, 2 * np.pi, 400)
x = 220 + 100 * np.cos(s)
y = 100 + 100 * np.sin(s)
init = np.array([x, y]).T
snake = active_contour(gaussian(img, 3),
init,
alpha=0.015,
beta=10,
gamma=0.001)
fig, ax = plt.subplots(figsize=(7, 7))
ax.imshow(img, cmap=plt.cm.gray)
ax.plot(init[:, 0], init[:, 1], '--r', lw=3)
ax.plot(snake[:, 0], snake[:, 1], '-b', lw=3)
ax.set_xticks([]), ax.set_yticks([])
ax.axis([0, img.shape[1], img.shape[0], 0])
#--------------------
img = data.text()
x = np.linspace(5, 424, 100)
y = np.linspace(136, 50, 100)
init = np.array([x, y]).T
snake = active_contour(gaussian(img, 1),
init,
bc='fixed',
alpha=0.1,
beta=1.0,
w_line=-5,
w_edge=0,
gamma=0.1)
fig, ax = plt.subplots(figsize=(9, 5))
ax.imshow(img, cmap=plt.cm.gray)
ax.plot(init[:, 0], init[:, 1], '--r', lw=3)
ax.plot(snake[:, 0], snake[:, 1], '-b', lw=3)
ax.set_xticks([]), ax.set_yticks([])
ax.axis([0, img.shape[1], img.shape[0], 0])
plt.show()
def line_detect():
im = data.text()
seg = im < 100
r = transform.radon(seg)
rho, theta = np.unravel_index(np.argmax(r), r.shape)
rho = rho - r.shape[0] / 2
x = np.int(rho * np.cos((theta + 90) * np.pi / 180) + im.shape[0] / 2)
y = np.int(rho * np.sin((theta + 90) * np.pi / 180) + im.shape[1] / 2)
dx = np.cos((theta) * np.pi / 180)
dy = np.sin((theta) * np.pi / 180)
l = 1000
res = im.copy()
cv2.line(res, (np.int(y - dy * l), np.int(x - dx * l)),
(np.int(y + dy * l), np.int(x + dx * l)), 255, 2)
io.imsave('text.png', im)
io.imsave('text-line.png', res)
def test_fixed_reference():
img = data.text()
r = np.linspace(136, 50, 100)
c = np.linspace(5, 424, 100)
init = np.array([r, c]).T
snake = active_contour(gaussian(img, 1),
init,
boundary_condition='fixed',
alpha=0.1,
beta=1.0,
w_line=-5,
w_edge=0,
gamma=0.1,
coordinates='rc')
refr = [136, 135, 134, 133, 132, 131, 129, 128, 127, 125]
refc = [5, 9, 13, 17, 21, 25, 30, 34, 38, 42]
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refr)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refc)
def test_free_reference():
img = data.text()
r = np.linspace(70, 40, 100)
c = np.linspace(5, 424, 100)
init = np.array([r, c]).T
snake = active_contour(gaussian(img, 3),
init,
boundary_condition='free',
alpha=0.1,
beta=1.0,
w_line=-5,
w_edge=0,
gamma=0.1,
coordinates='rc')
refr = [76, 76, 75, 74, 73, 72, 71, 70, 69, 69]
refc = [10, 13, 16, 19, 23, 26, 29, 32, 36, 39]
assert_equal(np.array(snake[:10, 0], dtype=np.int32), refr)
assert_equal(np.array(snake[:10, 1], dtype=np.int32), refc)
def profile():
import time
from iib.simulation import CLContext
from skimage import io, data, transform
gs, wgs = 256, 16
# Load some test data
r = transform.resize
sigs = np.empty((gs, gs, 4), np.float32)
sigs[:, :, 0] = r(data.coins().astype(np.float32) / 255.0, (gs, gs))
sigs[:, :, 1] = r(data.camera().astype(np.float32) / 255.0, (gs, gs))
sigs[:, :, 2] = r(data.text().astype(np.float32) / 255.0, (gs, gs))
sigs[:, :, 3] = r(data.checkerboard().astype(np.float32) / 255.0, (gs, gs))
sigs[:, :, 2] = r(io.imread("../scoring/corpus/rds/turing_001.png",
as_grey=True), (gs, gs))
sigs[:, :, 3] = io.imread("../scoring/corpus/synthetic/blobs.png",
as_grey=True)
sigs = sigs.reshape(gs*gs*4)
# Set up OpenCL
ctx = cl.create_some_context(interactive=False)
queue = cl.CommandQueue(ctx)
mf = cl.mem_flags
ifmt_f = cl.ImageFormat(cl.channel_order.RGBA, cl.channel_type.FLOAT)
bufi = cl.Image(ctx, mf.READ_ONLY, ifmt_f, (gs, gs))
cl.enqueue_copy(queue, bufi, sigs, origin=(0, 0), region=(gs, gs))
clctx = CLContext(ctx, queue, ifmt_f, gs, wgs)
# Compile the kernels
feats = cl.Program(ctx, features_cl()).build()
rdctn = cl.Program(ctx, reduction.reduction_sum_cl()).build()
blur2 = cl.Program(ctx, convolution.gaussian_cl([np.sqrt(2.0)]*4)).build()
blur4 = cl.Program(ctx, convolution.gaussian_cl([np.sqrt(4.0)]*4)).build()
iters = 500
t0 = time.time()
for i in range(iters):
get_features(clctx, feats, rdctn, blur2, blur4, bufi)
print((time.time() - t0)/iters)
imageio.imwrite(str(method_path) + '_out.png', output)
return self
elements = {
'disk(5)': morphology.disk(5),
}
defaults = {
'disk': morphology.disk(5),
'image_name': 'text_inverted',
'geometry': (0, 0, 90, 160), # row, col, rows, columns
}
# Alias some image names
data.blank = lambda: numpy.zeros(geo[2:4])
data.text_inverted = lambda: util.invert(data.text())
data.text_bw = lambda: data.bw_text()
data.text_bw_inverted = lambda: util.invert(data.bw_text())
with open('_data/categories.yaml') as stream:
try:
categories = yaml.safe_load(stream)
except yaml.YAMLError as exc:
print(exc)
def my_import (components):
the_module = __import__('.'.join(components))
for comp in components[1:]:
the_module = getattr(the_module, comp)
return the_module
# 线性拉伸对比度的例子
# http://scikit-image.org/docs/dev/user_guide/transforming_image_data.html#contrast-and-exposure
#
# Jianjiang Feng
# 2018.7.8
from skimage import data
from skimage import exposure
import matplotlib.pyplot as plt
import numpy as np
I = data.text()
#I = data.moon() # moon的极值是0和255
print('I: Min %d, Max %d' % (I.min(), I.max()))
I2 = exposure.rescale_intensity(I)
print('I2: Min %d, Max %d' % (I2.min(), I2.max()))
v_min, v_max = np.percentile(I, (0.2, 99.8))
print('I: PMin %d, PMax %d' % (v_min, v_max))
I3 = exposure.rescale_intensity(I, in_range=(v_min, v_max))
print('I3: Min %d, Max %d' % (I3.min(), I3.max()))
plt.figure(1)
plt.subplot(1, 3, 1)
plt.imshow(I, cmap='gray')
plt.subplot(1, 3, 2)
plt.imshow(I2, cmap='gray')
plt.subplot(1, 3, 3)
plt.imshow(I3, cmap='gray')
fig = plt.figure(figsize=(7, 7))
ax = fig.add_subplot(111)
plt.gray()
ax.imshow(img)
ax.plot(init[:, 0], init[:, 1], '--r', lw=3)
ax.plot(snake[:, 0], snake[:, 1], '-b', lw=3)
ax.set_xticks([]), ax.set_yticks([])
ax.axis([0, img.shape[1], img.shape[0], 0])
######################################################################
# Here we initialize a straight line between two points, `(5, 136)` and
# `(424, 50)`, and require that the spline has its end points there by giving
# the boundary condition `bc='fixed'`. We furthermore make the algorithm
# search for dark lines by giving a negative `w_line` value.
img = data.text()
x = np.linspace(5, 424, 100)
y = np.linspace(136, 50, 100)
init = np.array([x, y]).T
if new_scipy:
snake = active_contour(gaussian(img, 1), init, bc='fixed',
alpha=0.1, beta=1.0, w_line=-5, w_edge=0, gamma=0.1)
fig = plt.figure(figsize=(9, 5))
ax = fig.add_subplot(111)
plt.gray()
ax.imshow(img)
ax.plot(init[:, 0], init[:, 1], '--r', lw=3)
ax.plot(snake[:, 0], snake[:, 1], '-b', lw=3)
def test_triangle_uint_images():
text = cp.array(data.text())
assert threshold_triangle(cp.invert(text)) == 151
assert threshold_triangle(text) == 104
assert threshold_triangle(coinsd) == 80
assert threshold_triangle(cp.invert(coinsd)) == 175
"""
This example illustrates the use of the horizontal Sobel filter, to compute
horizontal gradients.
"""
from skimage import data, filter
import matplotlib.pyplot as plt
text = data.text()
hsobel_text = filter.hsobel(text)
plt.figure(figsize=(12, 3))
plt.subplot(121)
plt.imshow(text, cmap='gray', interpolation='nearest')
plt.axis('off')
plt.subplot(122)
plt.imshow(hsobel_text, cmap='jet', interpolation='nearest')
plt.axis('off')
plt.tight_layout()
plt.show()
from skimage import data, transform import numpy as np import matplotlib.pyplot as plt image = data.text() plt.imshow(image, cmap=plt.cm.gray) target = np.array(plt.ginput(4)) source = np.array([(0, 0), (0, 50), (300, 50), (300, 0)]) plt.close() pt = transform.ProjectiveTransform() pt.estimate(source, target) warped = transform.warp(image, pt, output_shape=(50, 300)) f, (ax0, ax1) = plt.subplots(1, 2) ax0.imshow(image, cmap=plt.cm.gray) ax1.imshow(warped, cmap=plt.cm.gray) plt.show()
# Фильтер Собеля для детектирования горизонтальных линий import numpy as np from skimage import morphology from skimage import exposure from matplotlib import pyplot as plt from skimage import data from skimage import filters text = data.text() hsobel_text = filters.sobel_h(text) plt.figure() plt.imshow(text, cmap='gray') plt.show() plt.figure() plt.imshow(hsobel_text, cmap='gray') plt.show() # Нелокальные фильтры используют все изображение или # его часть для изменения интенсивности в одном пикселе. # В примере показано изменение контрастности в областях. camera = data.camera() camera_equalized = exposure.equalize_hist(camera) # выравнивание гистограммы plt.figure() plt.imshow(camera, cmap='gray') plt.show() plt.figure() plt.imshow(camera_equalized, cmap='gray')
def test():
import matplotlib.pyplot as plt
from skimage import io, data, transform
from iib.simulation import CLContext
gs, wgs = 256, 16
# Load some test data
r = transform.resize
sigs = np.empty((gs, gs, 4), np.float32)
sigs[:, :, 0] = r(data.coins().astype(np.float32) / 255.0, (gs, gs))
sigs[:, :, 1] = r(data.camera().astype(np.float32) / 255.0, (gs, gs))
sigs[:, :, 2] = r(data.text().astype(np.float32) / 255.0, (gs, gs))
sigs[:, :, 3] = r(data.checkerboard().astype(np.float32) / 255.0, (gs, gs))
sigs[:, :, 2] = r(io.imread("../scoring/corpus/rds/turing_001.png",
as_grey=True), (gs, gs))
sigs[:, :, 3] = io.imread("../scoring/corpus/synthetic/blobs.png",
as_grey=True)
#sq = np.arange(256).astype(np.float32).reshape((16, 16)) / 255.0
#sigs[:, :, 0] = np.tile(sq, (16, 16))
sigs = sigs.reshape(gs*gs*4)
# Set up OpenCL
ctx = cl.create_some_context(interactive=False)
queue = cl.CommandQueue(ctx)
mf = cl.mem_flags
ifmt_f = cl.ImageFormat(cl.channel_order.RGBA, cl.channel_type.FLOAT)
bufi = cl.Image(ctx, mf.READ_ONLY, ifmt_f, (gs, gs))
cl.enqueue_copy(queue, bufi, sigs, origin=(0, 0), region=(gs, gs))
clctx = CLContext(ctx, queue, ifmt_f, gs, wgs)
# Compile the kernels
feats = cl.Program(ctx, features_cl()).build()
rdctn = cl.Program(ctx, reduction.reduction_sum_cl()).build()
blur2 = cl.Program(ctx, convolution.gaussian_cl([np.sqrt(2.0)]*4)).build()
blur4 = cl.Program(ctx, convolution.gaussian_cl([np.sqrt(4.0)]*4)).build()
entropy = get_entropy(clctx, feats, rdctn, bufi)
print("Average entropy:", entropy)
variance = get_variance(clctx, feats, rdctn, bufi)
print("Variance:", variance)
edges = get_edges(clctx, feats, rdctn, blur4, bufi, summarise=False)
edge_counts = get_edges(clctx, feats, rdctn, blur4, bufi)
print("Edge pixel counts:", edge_counts)
blobs = get_blobs(clctx, feats, rdctn, blur2, bufi, summarise=False)
features = get_features(clctx, feats, rdctn, blur2, blur4, bufi)
print("Feature vector:")
print(features)
# Plot the edges and blobs
for i in range(4):
plt.subplot(4, 3, i*3+1)
img = sigs.reshape((gs, gs, 4))[:, :, i]
plt.imshow(img, cmap="gray")
plt.xticks([])
plt.yticks([])
plt.subplot(4, 3, i*3+2)
img = edges.reshape((gs, gs, 4))[:, :, i]
plt.imshow(img, cmap="gray")
plt.xticks([])
plt.yticks([])
ax = plt.subplot(4, 3, i*3+3)
img = sigs.reshape((gs, gs, 4))[:, :, i]
plt.imshow(img, cmap="gray")
plt.xticks([])
plt.yticks([])
for j in range(len(blobs)):
sblobs = blobs[j]
s = 2**(j+1)
r = np.sqrt(2.0) * s
im = sblobs[:, :, i]
posns = np.transpose(im.nonzero()) * 2**(j+1)
for xy in posns:
circ = plt.Circle((xy[1], xy[0]), r, color="green", fill=False)
ax.add_patch(circ)
plt.show()
from matplotlib import pyplot as plt
from skimage import data, img_as_float
from skimage.feature import harris
def plot_harris_points(image, filtered_coords):
""" plots corners found in image"""
plt.imshow(image)
y, x = np.transpose(filtered_coords)
plt.plot(x, y, 'b.')
plt.axis('off')
# display results
plt.figure(figsize=(8, 3))
im_lena = img_as_float(data.lena())
im_text = img_as_float(data.text())
filtered_coords = harris(im_lena, min_distance=4)
plt.axes([0, 0, 0.3, 0.95])
plot_harris_points(im_lena, filtered_coords)
filtered_coords = harris(im_text, min_distance=4)
plt.axes([0.2, 0, 0.77, 1])
plot_harris_points(im_text, filtered_coords)
plt.show()
def normalize_img(img):
img /= np.max(img)
img = np.ceil(img * 255)
return img
def exponential_trans(img):
for row in range(img.shape[0]):
for column in range(img.shape[1]):
img[row][column] = math.exp(img[row][column])
return img
image_teste = data.text().astype(float)
exp_image = exponential_trans(image_teste.copy())
plt.imshow(exp_image, cmap='gray')
def potential_trans(img, gamma):
for row in range(img.shape[0]):
for column in range(img.shape[1]):
img[row][column] = img[row][column]**gamma
return normalize_img(img)
image2 = data.coins()
pot_image = potential_trans(image2.copy(), 0.2)
plt.imshow(pot_image, cmap='gray')
==================================
Demo of a CollectionViewer for viewing collections of images with the
`autolevel` rank filter connected as a plugin.
"""
from skimage import data
from skimage.filters import rank
from skimage.morphology import disk
from skimage.viewer import CollectionViewer
from skimage.viewer.widgets import Slider
from skimage.viewer.plugins.base import Plugin
# Wrap autolevel function to make the disk size a filter argument.
def autolevel(image, disk_size):
return rank.autolevel(image, disk(disk_size))
img_collection = [data.camera(), data.coins(), data.text()]
plugin = Plugin(image_filter=autolevel)
plugin += Slider('disk_size', 2, 8, value_type='int')
plugin.name = "Autolevel"
viewer = CollectionViewer(img_collection)
viewer += plugin
viewer.show()
#Program to get default images in scikit-image
from skimage import data
from skimage import io
#Get the camera image
img_camera = data.camera()
#Get an image with handwritten text
img_text = data.text()
io.show(img_text)
'''
File "skimage_data.py", line 12, in <module>
io.show(img_text)
TypeError: show() takes 0 positional arguments but 1 was given
'''
from skimage import data, img_as_float
from skimage.feature import harris
def plot_harris_points(image, filtered_coords):
""" plots corners found in image"""
plt.imshow(image)
y, x = np.transpose(filtered_coords)
plt.plot(x, y, 'b.')
plt.axis('off')
# display results
plt.figure(figsize=(8, 3))
im_lena = img_as_float(data.lena())
im_text = img_as_float(data.text())
filtered_coords = harris(im_lena, min_distance=4)
plt.axes([0, 0, 0.3, 0.95])
plot_harris_points(im_lena, filtered_coords)
filtered_coords = harris(im_text, min_distance=4)
plt.axes([0.2, 0, 0.77, 1])
plot_harris_points(im_text, filtered_coords)
plt.show()
canny_kwargs = dict([(k, kwargs.pop(k)) for k in canny_keys])
hough_kwargs = kwargs
edges = canny(image, **canny_kwargs)
lines = probabilistic_hough(edges, **hough_kwargs)
self._lines = lines
return edges
def display_filtered_image(self, edges):
self.overlay = edges
if hasattr(self, '_hough_lines'):
self.image_viewer.ax.collections.remove(self._hough_lines)
self._hough_lines = mcoll.LineCollection(self._lines, colors='r')
self.image_viewer.ax.add_collection(self._hough_lines)
self.image_viewer.redraw()
image = data.text()
# Note: ImageViewer must be called before Plugin b/c it starts the event loop.
viewer = ImageViewer(image)
# You can create a UI for a filter just by passing a filter function...
plugin = HoughPlugin()
plugin += Slider('sigma', 0, 5, value=1, update_on='release')
plugin += Slider('low threshold', 0, 255, update_on='release')
plugin += Slider('high threshold', 0, 255, update_on='release')
plugin += Slider('threshold', 0, 255, update_on='release')
plugin += Slider('line length', 0, 100, update_on='release')
plugin += Slider('line gap', 0, 20, update_on='release')
# Finally, attach the plugin to the image viewer.
viewer += plugin
viewer.show()
@author: jsaavedr
Adaptive Threhsolding
'''
import matplotlib.pyplot as plt
import skimage.filters as filters
import skimage.data as images
import numpy as np
import utils
import pai_io
if __name__ == '__main__' :
#filename = '../images/gray/car_1.png'
#image=pai_io.imread(filename, as_gray = True)
image = images.text()
print(image.shape)
#th_otsu = basis.get_threshold_otsu(image)
th_adaptive = filters.threshold_local(image, block_size = 21, offset = 15)
th_niblack = filters.threshold_niblack(image, window_size = 21, k=0.2)
th_sauvola = filters.threshold_sauvola(image, window_size = 21, k=0.2)
#bin_image_otsu = basis.threshold(image, th_otsu)
bin_image_adaptive = np.uint8(image > th_adaptive)
bin_image_niblack = np.uint8(image > th_niblack)
bin_image_sauvola = np.uint8(image > th_sauvola)
fig, xs = plt.subplots(1,3)
for i in range(3):
xs[i].set_axis_off()
xs[0].imshow(bin_image_adaptive*255, cmap = 'gray', vmin = 0, vmax = 255)
xs[0].set_title('Local')
xs[1].imshow(bin_image_niblack*255, cmap = 'gray', vmin = 0, vmax = 255)
def test_triangle_uint_images():
assert (threshold_triangle(np.invert(data.text())) == 151)
assert (threshold_triangle(data.text()) == 104)
assert (threshold_triangle(data.coins()) == 80)
assert (threshold_triangle(np.invert(data.coins())) == 175)
==================================
Demo of a CollectionViewer for viewing collections of images with the
`autolevel` rank filter connected as a plugin.
"""
from skimage import data
from skimage.filter import rank
from skimage.morphology import disk
from skimage.viewer import CollectionViewer
from skimage.viewer.widgets import Slider
from skimage.viewer.plugins.base import Plugin
# Wrap autolevel function to make the disk size a filter argument.
def autolevel(image, disk_size):
return rank.autolevel(image, disk(disk_size))
img_collection = [data.camera(), data.coins(), data.text()]
plugin = Plugin(image_filter=autolevel)
plugin += Slider("disk_size", 2, 8, value_type="int")
plugin.name = "Autolevel"
viewer = CollectionViewer(img_collection)
viewer += plugin
viewer.show()
def test_triangle_uint_images():
assert(threshold_triangle(np.invert(data.text())) == 151)
assert(threshold_triangle(data.text()) == 104)
assert(threshold_triangle(data.coins()) == 80)
assert(threshold_triangle(np.invert(data.coins())) == 175)
Created on Mon Aug 27 17:00:10 2018
Last Updated on Tue Aug 28 16:01:10 2018
@author: bhavani
"""
from skimage import io
img = io.imread("image.png")
io.imshow("image.png")
#io.show()
""" Writing or Saving an Image"""
io.imsave("new_image.png", img)
""" Data Module provides some standard test images """
from skimage import data
io.imshow(data.camera())
io.imshow(data.text())
io.show()
"""COlor module Contains methods to convert image from One to another color"""
from skimage import color
img = io.imread("BusinessCard.JPEG")
io.imshow("BusinessCard.JPEG")
gray = color.rgb2gray(img)
io.imshow(gray)
io.show()
io.imsave("Gray_BusinessCard.png", gray)
#Convert RGB to HSV
img = data.astronaut()
img_hsv = color.rgb2hsv(img)
io.imshow(img_hsv)
def test_text():
""" Test that "text" image can be loaded. """
data.text()
def test_triangle_images():
assert threshold_triangle(np.invert(data.text())) == 151
assert threshold_triangle(data.text()) == 104
assert threshold_triangle(data.coins()) == 80
assert threshold_triangle(np.invert(data.coins())) == 175
