diff --git a/.travis.yml b/.travis.yml index f50ba1ac..3a127d3d 100644 --- a/.travis.yml +++ b/.travis.yml @@ -1,7 +1,7 @@ # vim ft=yaml # travis-ci.org definition for skimage build # -# We pretend to be erlang because we need can't use the python support in +# We pretend to be erlang because we can't use the python support in # travis-ci; it uses virtualenvs, they do not have numpy, scipy, matplotlib, # and it is impractical to build them diff --git a/doc/examples/plot_hough_transform.py b/doc/examples/plot_hough_transform.py index b74132da..b15df92e 100644 --- a/doc/examples/plot_hough_transform.py +++ b/doc/examples/plot_hough_transform.py @@ -59,7 +59,7 @@ References ''' -from skimage.transform import hough, hough_peaks, probabilistic_hough +from skimage.transform import hough_line, hough_peaks, probabilistic_hough from skimage.filter import canny from skimage import data @@ -77,7 +77,7 @@ idx = np.arange(25, 75) image[idx[::-1], idx] = 255 image[idx, idx] = 255 -h, theta, d = hough(image) +h, theta, d = hough_line(image) plt.figure(figsize=(8, 4)) diff --git a/doc/source/plots/hough_tf.py b/doc/source/plots/hough_tf.py index 8b745864..ea2fc4bb 100644 --- a/doc/source/plots/hough_tf.py +++ b/doc/source/plots/hough_tf.py @@ -1,7 +1,7 @@ import numpy as np import matplotlib.pyplot as plt -from skimage.transform import hough +from skimage.transform import hough_line img = np.zeros((100, 150), dtype=bool) img[30, :] = 1 @@ -11,7 +11,7 @@ for i in range(90): img[i, i] = 1 img += np.random.random(img.shape) > 0.95 -out, angles, d = hough(img) +out, angles, d = hough_line(img) plt.subplot(1, 2, 1) @@ -20,8 +20,8 @@ plt.title('Input image') plt.subplot(1, 2, 2) plt.imshow(out, cmap=plt.cm.bone, - extent=(d[0], d[-1], - np.rad2deg(angles[0]), np.rad2deg(angles[-1]))) + extent=(np.rad2deg(angles[0]), np.rad2deg(angles[-1]), + d[0], d[-1])) plt.title('Hough transform') plt.xlabel('Angle (degree)') plt.ylabel('Distance (pixel)') diff --git a/skimage/draw/_draw.pyx b/skimage/draw/_draw.pyx index 4316cadc..ee2b89e0 100644 --- a/skimage/draw/_draw.pyx +++ b/skimage/draw/_draw.pyx @@ -293,12 +293,12 @@ def ellipse_perimeter(Py_ssize_t cy, Py_ssize_t cx, Py_ssize_t yradius, cy, cx : int Centre coordinate of ellipse. yradius, xradius: int - Main radial values. + Minor and major semi-axes. ``(x/xradius)**2 + (y/yradius)**2 = 1``. Returns ------- rr, cc : (N,) ndarray of int - Indices of pixels that belong to the circle perimeter. + Indices of pixels that belong to the ellipse perimeter. May be used to directly index into an array, e.g. ``img[rr, cc] = 1``. diff --git a/skimage/transform/hough_transform.py b/skimage/transform/hough_transform.py index e83cecd5..f112a025 100644 --- a/skimage/transform/hough_transform.py +++ b/skimage/transform/hough_transform.py @@ -124,6 +124,12 @@ def hough_line(img, theta=None): distances : ndarray Distance values. + Notes + ----- + The origin is the top left corner of the original image. + The angle is counted clockwise from 9 o'clock. + The distance is the minimal algebraic distance from this origin to the line. + Examples -------- Generate a test image: @@ -138,7 +144,7 @@ def hough_line(img, theta=None): Apply the Hough transform: - >>> out, angles, d = hough(img) + >>> out, angles, d = hough_line(img) .. plot:: hough_tf.py @@ -178,12 +184,12 @@ def hough_peaks(hspace, angles, dists, min_distance=10, min_angle=10, Parameters ---------- hspace : (N, M) array - Hough space returned by the `hough` function. + Hough space returned by the `hough_line` function. angles : (M,) array - Angles returned by the `hough` function. Assumed to be continuous + Angles returned by the `hough_line` function. Assumed to be continuous (`angles[-1] - angles[0] == PI`). dists : (N, ) array - Distances returned by the `hough` function. + Distances returned by the `hough_line` function. min_distance : int Minimum distance separating lines (maximum filter size for first dimension of hough space). @@ -204,14 +210,14 @@ def hough_peaks(hspace, angles, dists, min_distance=10, min_angle=10, Examples -------- >>> import numpy as np - >>> from skimage.transform import hough, hough_peaks + >>> from skimage.transform import hough_line, hough_peaks >>> from skimage.draw import line >>> img = np.zeros((15, 15), dtype=np.bool_) >>> rr, cc = line(0, 0, 14, 14) >>> img[rr, cc] = 1 >>> rr, cc = line(0, 14, 14, 0) >>> img[cc, rr] = 1 - >>> hspace, angles, dists = hough(img) + >>> hspace, angles, dists = hough_line(img) >>> hspace, angles, dists = hough_peaks(hspace, angles, dists) >>> angles array([ 0.74590887, -0.79856126])