79 lines
2.1 KiB
Python
79 lines
2.1 KiB
Python
|
#! /usr/bin/env python
|
||
|
|
|
||
|
|
print "OpenCV Python version of convexhull"
|
||
|
|
|
||
|
|
# import the necessary things for OpenCV
|
||
|
|
from opencv import cv
|
||
|
|
from opencv import highgui
|
||
|
|
|
||
|
|
# to generate random values
|
||
|
|
import random
|
||
|
|
|
||
|
|
# how many points we want at max
|
||
|
|
_MAX_POINTS = 100
|
||
|
|
|
||
|
|
if __name__ == '__main__':
|
||
|
|
|
||
|
|
# main object to get random values from
|
||
|
|
my_random = random.Random ()
|
||
|
|
|
||
|
|
# create the image where we want to display results
|
||
|
|
image = cv.cvCreateImage (cv.cvSize (500, 500), 8, 3)
|
||
|
|
|
||
|
|
# create the window to put the image in
|
||
|
|
highgui.cvNamedWindow ('hull', highgui.CV_WINDOW_AUTOSIZE)
|
||
|
|
|
||
|
|
while True:
|
||
|
|
# do forever
|
||
|
|
|
||
|
|
# get a random number of points
|
||
|
|
count = my_random.randrange (0, _MAX_POINTS) + 1
|
||
|
|
|
||
|
|
# initialisations
|
||
|
|
points = []
|
||
|
|
|
||
|
|
for i in range (count):
|
||
|
|
# generate a random point
|
||
|
|
points.append (cv.cvPoint (
|
||
|
|
my_random.randrange (0, image.width / 2) + image.width / 4,
|
||
|
|
my_random.randrange (0, image.width / 2) + image.width / 4
|
||
|
|
))
|
||
|
|
|
||
|
|
# compute the convex hull
|
||
|
|
hull = cv.cvConvexHull2 (points, cv.CV_CLOCKWISE, 0)
|
||
|
|
|
||
|
|
# start with an empty image
|
||
|
|
cv.cvSetZero (image)
|
||
|
|
|
||
|
|
for i in range (count):
|
||
|
|
# draw all the points
|
||
|
|
cv.cvCircle (image, points [i], 2,
|
||
|
|
cv.cvScalar (0, 0, 255, 0),
|
||
|
|
cv.CV_FILLED, cv.CV_AA, 0)
|
||
|
|
|
||
|
|
# start the line from the last point
|
||
|
|
pt0 = points [hull [-1]]
|
||
|
|
|
||
|
|
for point_index in hull:
|
||
|
|
# connect the previous point to the current one
|
||
|
|
|
||
|
|
# get the current one
|
||
|
|
pt1 = points [point_index]
|
||
|
|
|
||
|
|
# draw
|
||
|
|
cv.cvLine (image, pt0, pt1,
|
||
|
|
cv.cvScalar (0, 255, 0, 0),
|
||
|
|
1, cv.CV_AA, 0)
|
||
|
|
|
||
|
|
# now, current one will be the previous one for the next iteration
|
||
|
|
pt0 = pt1
|
||
|
|
|
||
|
|
# display the final image
|
||
|
|
highgui.cvShowImage ('hull', image)
|
||
|
|
|
||
|
|
# handle events, and wait a key pressed
|
||
|
|
k = highgui.cvWaitKey (0)
|
||
|
|
if k == '\x1b':
|
||
|
|
# user has press the ESC key, so exit
|
||
|
|
break
|