用python画圆角矩形_如何用OpenCV绘制圆角矩形（带圆角的矩形）？
这里是一个Python实现(万一有人一直在寻找一个)：它绘制一个圆角(随机半径和线厚度的改变---如果你想)边界周围的图像：
def addRoundedRectangleBorder(img):
height, width, channels = img.shape
border_radius = int(width * random.randint(1, 10)/100.0)
line_thickness = int(max(width, height) * random.randint(1, 3)/100.0)
edge_shift = int(line_thickness/2.0)
red = random.randint(230,255)
green = random.randint(230,255)
blue = random.randint(230,255)
color = (blue, green, red)
#draw lines
#top
cv2.line(img, (border_radius, edge_shift),
(width - border_radius, edge_shift), (blue, green, red), line_thickness)
#bottom
cv2.line(img, (border_radius, height-line_thickness),
(width - border_radius, height-line_thickness), (blue, green, red), line_thickness)
#left
cv2.line(img, (edge_shift, border_radius),
(edge_shift, height - border_radius), (blue, green, red), line_thickness)
#right
cv2.line(img, (width - line_thickness, border_radius),
(width - line_thickness, height - border_radius), (blue, green, red), line_thickness)
#corners
cv2.ellipse(img, (border_radius+ edge_shift, border_radius+edge_shift),
(border_radius, border_radius), 180, 0, 90, color, line_thickness)
cv2.ellipse(img, (width-(border_radius+line_thickness), border_radius),
(border_radius, border_radius), 270, 0, 90, color, line_thickness)
cv2.ellipse(img, (width-(border_radius+line_thickness), height-(border_radius + line_thickness)),
(border_radius, border_radius), 10, 0, 90, color, line_thickness)
cv2.ellipse(img, (border_radius+edge_shift, height-(border_radius + line_thickness)),
(border_radius, border_radius), 90, 0, 90, color, line_thickness)
return img