mirror of https://github.com/opencv/opencv.git
Open Source Computer Vision Library
https://opencv.org/
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
84 lines
2.2 KiB
84 lines
2.2 KiB
#!/usr/bin/env python |
|
|
|
''' |
|
Coherence-enhancing filtering example |
|
===================================== |
|
|
|
inspired by |
|
Joachim Weickert "Coherence-Enhancing Shock Filters" |
|
http://www.mia.uni-saarland.de/Publications/weickert-dagm03.pdf |
|
''' |
|
|
|
import numpy as np |
|
import cv2 as cv |
|
|
|
def coherence_filter(img, sigma = 11, str_sigma = 11, blend = 0.5, iter_n = 4): |
|
h, w = img.shape[:2] |
|
|
|
for i in range(iter_n): |
|
print(i) |
|
|
|
gray = cv.cvtColor(img, cv.COLOR_BGR2GRAY) |
|
eigen = cv.cornerEigenValsAndVecs(gray, str_sigma, 3) |
|
eigen = eigen.reshape(h, w, 3, 2) # [[e1, e2], v1, v2] |
|
x, y = eigen[:,:,1,0], eigen[:,:,1,1] |
|
|
|
gxx = cv.Sobel(gray, cv.CV_32F, 2, 0, ksize=sigma) |
|
gxy = cv.Sobel(gray, cv.CV_32F, 1, 1, ksize=sigma) |
|
gyy = cv.Sobel(gray, cv.CV_32F, 0, 2, ksize=sigma) |
|
gvv = x*x*gxx + 2*x*y*gxy + y*y*gyy |
|
m = gvv < 0 |
|
|
|
ero = cv.erode(img, None) |
|
dil = cv.dilate(img, None) |
|
img1 = ero |
|
img1[m] = dil[m] |
|
img = np.uint8(img*(1.0 - blend) + img1*blend) |
|
print('done') |
|
return img |
|
|
|
|
|
def main(): |
|
import sys |
|
try: |
|
fn = sys.argv[1] |
|
except: |
|
fn = 'baboon.jpg' |
|
|
|
src = cv.imread(cv.samples.findFile(fn)) |
|
|
|
def nothing(*argv): |
|
pass |
|
|
|
def update(): |
|
sigma = cv.getTrackbarPos('sigma', 'control')*2+1 |
|
str_sigma = cv.getTrackbarPos('str_sigma', 'control')*2+1 |
|
blend = cv.getTrackbarPos('blend', 'control') / 10.0 |
|
print('sigma: %d str_sigma: %d blend_coef: %f' % (sigma, str_sigma, blend)) |
|
dst = coherence_filter(src, sigma=sigma, str_sigma = str_sigma, blend = blend) |
|
cv.imshow('dst', dst) |
|
|
|
cv.namedWindow('control', 0) |
|
cv.createTrackbar('sigma', 'control', 9, 15, nothing) |
|
cv.createTrackbar('blend', 'control', 7, 10, nothing) |
|
cv.createTrackbar('str_sigma', 'control', 9, 15, nothing) |
|
|
|
|
|
print('Press SPACE to update the image\n') |
|
|
|
cv.imshow('src', src) |
|
update() |
|
while True: |
|
ch = cv.waitKey() |
|
if ch == ord(' '): |
|
update() |
|
if ch == 27: |
|
break |
|
|
|
print('Done') |
|
|
|
|
|
if __name__ == '__main__': |
|
print(__doc__) |
|
main() |
|
cv.destroyAllWindows()
|
|
|