def draw_keypoints(img, keypoints, draw_prob):
"""Draws for each keypoint a circle (roughly matching the sigma of the scale)
with a line for the orientation.
Args:
img The image to which to add the keypoints (gets copied)
keypoints The keypoints to draw
draw_prob Probability of drawing a keypoint (the lower the less keypoints are drawn)
Returns:
Image with keypoints"""
height, width = img.shape
img = np.copy(img)
# convert from grayscale image to RGB so that keypoints can be drawn in red
img = img[:, :, np.newaxis]
img = np.repeat(img, 3, axis=2)
for (y, x), orientation, scale_idx, scale_size, kp_type in keypoints:
if draw_prob < 1.0 and random.random() <= draw_prob:
# draw the circle
radius = int(scale_size)
rr, cc = draw.circle_perimeter(y, x, radius, shape=img.shape)
img[rr, cc, 0] = 1.0
img[rr, cc, 1:] = 0
# draw orientation
orientation = util.quantize(orientation, [-135, -90, -45, 0, 45, 90, 135, 180])
x_start = x
y_start = y
if orientation == 0:
x_end = x + radius
y_end = y
elif orientation == 45:
x_end = x + radius*(1/math.sqrt(2))
y_end = y + radius*(1/math.sqrt(2))
elif orientation == 90:
x_end = x
y_end = y + radius
elif orientation == 135:
x_end = x - radius*(1/math.sqrt(2))
y_end = y - radius*(1/math.sqrt(2))
elif orientation == 180:
x_end = x - radius
y_end = y
elif orientation == -135:
x_end = x - radius*(1/math.sqrt(2))
y_end = y - radius*(1/math.sqrt(2))
elif orientation == -90:
x_end = x
y_end = y - radius
elif orientation == -45:
x_end = x + radius*(1/math.sqrt(2))
y_end = y - radius*(1/math.sqrt(2))
x_end = np.clip(x_end, 0, width-1)
y_end = np.clip(y_end, 0, height-1)
rr, cc = draw.line(int(y_start), int(x_start), int(y_end), int(x_end))
img[rr, cc, 0] = 1.0
img[rr, cc, 1:] = 0
img = np.clip(img, 0, 1.0)
return img
评论列表
文章目录
