Skip to content


Subversion checkout URL

You can clone with
Download ZIP
branch: master
Fetching contributors…

Cannot retrieve contributors at this time

22 lines (18 sloc) 0.721 kB
import numpy as np
from numpy import sum, trunc, pi, sin, cos, exp
import scipy.optimize
def refine_circle((cx0,cy0), r0, img):
thetas = np.linspace(0, 2*pi, 100)
sigma = 2
delta = 3*sigma
def opt((cx,cy,r)):
def f(theta):
x = int(cx + r*cos(theta))
y = int(cy + r*sin(theta))
xs,ys = np.ogrid[x-delta:x+delta:1, y-delta:y+delta:1]
weights = 1./2/pi * exp(-((xs-x)**2 + (ys-y)**2) / 2 * sigma)
return np.average(img[xs,ys], weights=weights)
return -sum(f(theta) for theta in thetas)
(cx,cy,r) = scipy.optimize.fmin(opt, np.array([cx0, cy0, r0]))
print "Refined circle", (cx,cy), "radius", r
return ((cx,cy),r)
Jump to Line
Something went wrong with that request. Please try again.