opencv/samples/python2/distrans.py
2013-04-12 19:37:40 +04:00

71 lines
1.4 KiB
Python
Executable File

#!/usr/bin/env python
'''
Distance transform sample.
Usage:
distrans.py [<image>]
Keys:
ESC - exit
v - toggle voronoi mode
'''
import numpy as np
import cv2
from common import make_cmap
if __name__ == '__main__':
import sys
try:
fn = sys.argv[1]
except:
fn = '../cpp/fruits.jpg'
print __doc__
img = cv2.imread(fn, 0)
if img is None:
print 'Failed to load fn:', fn
sys.exit(1)
cm = make_cmap('jet')
need_update = True
voronoi = False
def update(dummy=None):
global need_update
need_update = False
thrs = cv2.getTrackbarPos('threshold', 'distrans')
mark = cv2.Canny(img, thrs, 3*thrs)
dist, labels = cv2.distanceTransformWithLabels(~mark, cv2.DIST_L2, 5)
if voronoi:
vis = cm[np.uint8(labels)]
else:
vis = cm[np.uint8(dist*2)]
vis[mark != 0] = 255
cv2.imshow('distrans', vis)
def invalidate(dummy=None):
global need_update
need_update = True
cv2.namedWindow('distrans')
cv2.createTrackbar('threshold', 'distrans', 60, 255, invalidate)
update()
while True:
ch = 0xFF & cv2.waitKey(50)
if ch == 27:
break
if ch == ord('v'):
voronoi = not voronoi
print 'showing', ['distance', 'voronoi'][voronoi]
update()
if need_update:
update()
cv2.destroyAllWindows()