# Copyright (c) 2016 Weitian LI # MIT license # ############################################################################## # Copyright (C) 2011, the scikit-image team # All rights reserved. # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # 1. Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # 2. Redistributions in binary form must reproduce the above copyright # notice, this list of conditions and the following disclaimer in # the documentation and/or other materials provided with the # distribution. # 3. Neither the name of skimage nor the names of its contributors may be # used to endorse or promote products derived from this software without # specific prior written permission. # THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR # IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED # WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE # DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, # INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES # (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR # SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) # HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, # STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING # IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE # POSSIBILITY OF SUCH DAMAGE. """ Generic drawers (a.k.a. painters) that draw some commonly used shapes. DISCLAIMER ---------- The following functions are taken from project [scikit-image]_, which are licensed under the *Modified BSD* license: - ``_ellipse_in_shape()`` - ``ellipse()`` - ``circle()`` Credits ------- .. [scikit-image] skimage.draw.draw http://scikit-image.org/docs/dev/api/skimage.draw.html https://github.com/scikit-image/scikit-image/blob/master/skimage/draw/draw.py """ import numpy as np import numba as nb @nb.jit([nb.types.UniTuple(nb.int64[:], 2)(nb.types.UniTuple(nb.int64, 2), nb.types.UniTuple(nb.int64, 2), nb.types.UniTuple(nb.int64, 2)), nb.types.UniTuple(nb.int64[:], 2)(nb.int64[:], nb.int64[:], nb.int64[:])], nopython=True) def _ellipse_in_shape(shape, center, radii): """Generate coordinates of points within the ellipse bounded by shape.""" # XXX: ``numba`` currently does not support ``numpy.meshgrid`` nrow, ncol = shape r_lim = np.zeros((nrow, ncol)) for i in range(nrow): r_lim[i, :] = np.arange(float(ncol)) c_lim = np.zeros((nrow, ncol)) for i in range(ncol): c_lim[:, i] = np.arange(float(nrow)) # r_o, c_o = center r_r, c_r = radii distances = (((r_lim-r_o) / r_r) * ((r_lim-r_o) / r_r) + ((c_lim-c_o) / c_r) * ((c_lim-c_o / c_r))) xi, yi = np.nonzero(distances < 1.0) return (xi, yi) @nb.jit(nb.types.UniTuple(nb.int64[:], 2)(nb.int64, nb.int64, nb.int64, nb.int64, nb.types.UniTuple(nb.int64, 2)), nopython=True) def ellipse(r, c, r_radius, c_radius, shape): """Generate coordinates of pixels within the ellipse. XXX/NOTE -------- * Cannot figure out why ``nb.optional(nb.types.UniTuple(nb.int64, 2))`` does NOT work. Therefore, make ``shape`` as mandatory parameter instead of optional. * Cannot figure out multi-dispatch that allows both int and float types for ``r``, ``c``, ``r_radius`` and ``c_radius``. Thus only support the int type for the moment. Parameters ---------- r, c : int Center coordinate of the ellipse. r_radius, c_radius : int Minor and major semi-axes. ``(r/r_radius)**2 + (c/c_radius)**2 = 1``. shape : tuple Image shape which is used to determine the maximum extent of output pixel coordinates. This is useful for ellipses that exceed the image size. If None, the full extent of the ellipse is used. Returns ------- rr, cc : integer `~numpy.ndarray` Pixel coordinates of the ellipse. May be used to directly index into an array, e.g. ``img[rr, cc] = 1``. Examples -------- >>> from fg21sim.utils.draw import ellipse >>> img = np.zeros((10, 10), dtype=np.uint8) >>> rr, cc = ellipse(5, 5, 3, 4) >>> img[rr, cc] = 1 >>> img array([[0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 1, 1, 1, 1, 1, 0, 0], [0, 0, 1, 1, 1, 1, 1, 1, 1, 0], [0, 0, 1, 1, 1, 1, 1, 1, 1, 0], [0, 0, 1, 1, 1, 1, 1, 1, 1, 0], [0, 0, 0, 1, 1, 1, 1, 1, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]], dtype=uint8) """ center = np.array([r, c]) radii = np.array([r_radius, c_radius]) # The upper_left and lower_right corners of the # smallest rectangle containing the ellipse. upper_left = np.ceil(center - radii).astype(np.int64) lower_right = np.floor(center + radii).astype(np.int64) # Constrain upper_left and lower_right by shape boundary. upper_left = np.maximum(upper_left, np.array([0, 0])) lower_right = np.minimum(lower_right, np.array(shape)-1) shifted_center = center - upper_left bounding_shape = lower_right - upper_left + 1 rr, cc = _ellipse_in_shape(bounding_shape, shifted_center, radii) rr += upper_left[0] cc += upper_left[1] return (rr, cc) def circle(r, c, radius, shape): """Generate coordinates of pixels within the circle. Parameters ---------- r, c : int Center coordinate of the circle. radius : int Radius of the circle. shape : tuple Image shape which is used to determine the maximum extent of output pixel coordinates. This is useful for circles that exceed the image size. If None, the full extent of the circle is used. Returns ------- rr, cc : integer `~numpy.ndarray` Pixel coordinates of the circle. May be used to directly index into an array, e.g. ``img[rr, cc] = 1``. Examples -------- >>> from fg21sim.utils.draw import circle >>> img = np.zeros((10, 10), dtype=np.uint8) >>> rr, cc = circle(4, 4, 5) >>> img[rr, cc] = 1 >>> img array([[0, 0, 1, 1, 1, 1, 1, 0, 0, 0], [0, 1, 1, 1, 1, 1, 1, 1, 0, 0], [1, 1, 1, 1, 1, 1, 1, 1, 1, 0], [1, 1, 1, 1, 1, 1, 1, 1, 1, 0], [1, 1, 1, 1, 1, 1, 1, 1, 1, 0], [1, 1, 1, 1, 1, 1, 1, 1, 1, 0], [1, 1, 1, 1, 1, 1, 1, 1, 1, 0], [0, 1, 1, 1, 1, 1, 1, 1, 0, 0], [0, 0, 1, 1, 1, 1, 1, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]], dtype=uint8) """ return ellipse(r, c, radius, radius, shape)