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psf/black code formatting (#1277)

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This commit is contained in:
William Zhang
2019-10-05 01:14:13 -04:00
committed by Christian Clauss
parent 07f04a2e55
commit 9eac17a408
291 changed files with 6014 additions and 4571 deletions
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46
digital_image_processing/edge_detection/canny.py
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@ -8,8 +8,12 @@ PI = 180
def gen_gaussian_kernel(k_size, sigma):
center = k_size // 2
x, y = np.mgrid[0 - center:k_size - center, 0 - center:k_size - center]
g = 1 / (2 * np.pi * sigma) * np.exp(-(np.square(x) + np.square(y)) / (2 * np.square(sigma)))
x, y = np.mgrid[0 - center : k_size - center, 0 - center : k_size - center]
g = (
1
/ (2 * np.pi * sigma)
* np.exp(-(np.square(x) + np.square(y)) / (2 * np.square(sigma)))
)
return g
@ -34,27 +38,33 @@ def canny(image, threshold_low=15, threshold_high=30, weak=128, strong=255):
if (
0 <= direction < 22.5
or 15 * PI / 8 <= direction <= 2 * PI
or 7 * PI / 8 <= direction <= 9 * PI / 8
or 15 * PI / 8 <= direction <= 2 * PI
or 7 * PI / 8 <= direction <= 9 * PI / 8
):
W = sobel_grad[row, col - 1]
E = sobel_grad[row, col + 1]
if sobel_grad[row, col] >= W and sobel_grad[row, col] >= E:
dst[row, col] = sobel_grad[row, col]
elif (PI / 8 <= direction < 3 * PI / 8) or (9 * PI / 8 <= direction < 11 * PI / 8):
elif (PI / 8 <= direction < 3 * PI / 8) or (
9 * PI / 8 <= direction < 11 * PI / 8
):
SW = sobel_grad[row + 1, col - 1]
NE = sobel_grad[row - 1, col + 1]
if sobel_grad[row, col] >= SW and sobel_grad[row, col] >= NE:
dst[row, col] = sobel_grad[row, col]
elif (3 * PI / 8 <= direction < 5 * PI / 8) or (11 * PI / 8 <= direction < 13 * PI / 8):
elif (3 * PI / 8 <= direction < 5 * PI / 8) or (
11 * PI / 8 <= direction < 13 * PI / 8
):
N = sobel_grad[row - 1, col]
S = sobel_grad[row + 1, col]
if sobel_grad[row, col] >= N and sobel_grad[row, col] >= S:
dst[row, col] = sobel_grad[row, col]
elif (5 * PI / 8 <= direction < 7 * PI / 8) or (13 * PI / 8 <= direction < 15 * PI / 8):
elif (5 * PI / 8 <= direction < 7 * PI / 8) or (
13 * PI / 8 <= direction < 15 * PI / 8
):
NW = sobel_grad[row - 1, col - 1]
SE = sobel_grad[row + 1, col + 1]
if sobel_grad[row, col] >= NW and sobel_grad[row, col] >= SE:
@ -82,14 +92,14 @@ def canny(image, threshold_low=15, threshold_high=30, weak=128, strong=255):
for col in range(1, image_col):
if dst[row, col] == weak:
if 255 in (
dst[row, col + 1],
dst[row, col - 1],
dst[row - 1, col],
dst[row + 1, col],
dst[row - 1, col - 1],
dst[row + 1, col - 1],
dst[row - 1, col + 1],
dst[row + 1, col + 1],
dst[row, col + 1],
dst[row, col - 1],
dst[row - 1, col],
dst[row + 1, col],
dst[row - 1, col - 1],
dst[row + 1, col - 1],
dst[row - 1, col + 1],
dst[row + 1, col + 1],
):
dst[row, col] = strong
else:
@ -98,10 +108,10 @@ def canny(image, threshold_low=15, threshold_high=30, weak=128, strong=255):
return dst
if __name__ == '__main__':
if __name__ == "__main__":
# read original image in gray mode
lena = cv2.imread(r'../image_data/lena.jpg', 0)
lena = cv2.imread(r"../image_data/lena.jpg", 0)
# canny edge detection
canny_dst = canny(lena)
cv2.imshow('canny', canny_dst)
cv2.imshow("canny", canny_dst)
cv2.waitKey(0)