1 __author__ = "WSX"
2 import cv2 as cv
3 import numpy as np
4 # 基于拓扑结构来发现和绘制（边缘提取）
5 # cv.findContours() 发现轮廓
6 # cv.drawContours() 绘制轮廓
7 # 使用梯度 ，不需要阈值了就
8
9 def edge_demo(image):
10 blurred = cv.GaussianBlur(image, (3, 3), 0)
11 gray = cv.cvtColor(blurred, cv.COLOR_BGR2GRAY)
12 # X Gradient
13 xgrad = cv.Sobel(gray, cv.CV_16SC1, 1, 0)
14 # Y Gradient
15 ygrad = cv.Sobel(gray, cv.CV_16SC1, 0, 1)
16 #edge
17 #edge_output = cv.Canny(xgrad, ygrad, 50, 150)
18 edge_output = cv.Canny(gray, 30, 100)
19 cv.imshow("Canny Edge", edge_output)
20 return edge_output
21
22
23 def contours_demo(image):
24 """dst = cv.GaussianBlur(image, (3, 3), 0)
25 gray = cv.cvtColor(dst, cv.COLOR_BGR2GRAY)
26 ret, binary = cv.threshold(gray, 0, 255, cv.THRESH_BINARY | cv.THRESH_OTSU)
27 cv.imshow("binary image", binary)"""
28 binary = edge_demo(image)
29
30 cloneImage, contours, heriachy = cv.findContours(binary, cv.RETR_EXTERNAL, cv.CHAIN_APPROX_SIMPLE)
31 # cv.RETR_EXTERNAL最大轮廓 CHAIN_APPROX_SIMPLE简单的
32 #contours 放轮廓 heriachy层次信息
33 for i, contour in enumerate(contours):
34 cv.drawContours(image, contours, i, (0, 0, 255), 2)
35 #绘制(0, 0, 255)颜色 2 为宽度 若为-1 则填充轮廓
36 approxCurve = cv.approxPolyDP(contour, 4, True)
37 if approxCurve.shape[0] > 6:
38 cv.drawContours(image, contours, i, (0, 255, 255), 2)
39 if approxCurve.shape[0] == 4:
40 cv.drawContours(image, contours, i, (255, 255, 0), 2)
41 print(approxCurve.shape[0])
42 print(i)
43 cv.imshow("detect contours", image)
44
45 def main():
46 img = cv.imread("1.JPG")
47 cv.namedWindow("Show", cv.WINDOW_AUTOSIZE)
48 cv.imshow("Show", img)
49
50 contours_demo(img)
51 cv.waitKey(0)
52 cv.destroyAllWindows()
53
54 main()
