opencv 相关

Posted 2020-10-31 shepherd2015

主要是用opencv的python接口，偶尔用用opencv的C++接口

 

一，响应鼠标事件，画框。参考的是opencv sample里头的 grabCut.py

 1 #!/usr/bin/env python3
 2 # -*- coding: utf-8 -*-
 3 """
 4 Created on Sat Apr 21 09:45:16 2018
 5 
 6 @author: scj
 7 """
 8 
 9 import numpy as np
10 import cv2
11 import sys
12 
13 filename = ‘./1.jpg‘
14 
15 img = cv2.imread(filename)
16 rows = img.shape[0]
17 cols = img.shape[1]
18 size = (int(cols*0.5), int(rows*0.5))  
19 img = cv2.resize(img, size, interpolation=cv2.INTER_AREA)
20 img2 = img.copy()
21 
22 
23 BLUE  = [255,   0,   0]   # rectangle color
24 
25 def onmouse(event,x,y,flags,param):
26     global img,img2,drawing,value,mask,rectangle,rect,rect_or_mask,ix,iy,rect_over
27 
28     # Draw Rectangle
29     if event == cv2.EVENT_LBUTTONDOWN:
30         rectangle = True
31         ix,iy = x,y
32 
33     elif event == cv2.EVENT_MOUSEMOVE:
34         if rectangle == True:
35             img = img2.copy()
36             cv2.rectangle(img,(ix,iy),(x,y),BLUE,2)
37             rect = (min(ix,x),min(iy,y),abs(ix-x),abs(iy-y))
38 #            rect_or_mask = 0
39 
40     elif event == cv2.EVENT_LBUTTONUP:
41         rectangle = False
42         rect_over = True
43         cv2.rectangle(img,(ix,iy),(x,y),BLUE,2)
44         rect = (min(ix,x),min(iy,y),abs(ix-x),abs(iy-y))
45 #        rect_or_mask = 0
46 #        print(" Now press the key ‘n‘ a few times until no further change \n")
47         print("press any key to stop")
48         print("get a rectangle from (", str(ix), ", ", str(iy), ") to (" , str(x), ", ", str(y) ,") \n")
49 
50 
51 cv2.namedWindow(‘input‘)
52 cv2.setMouseCallback(‘input‘,onmouse)
53 
54 while(1):
55     cv2.imshow(‘input‘,img)
56     k = cv2.waitKey(1)
57     
58     if(k>0):
59         cv2.destroyAllWindows()
60         break;

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二，C++中保存Mat成xml，然后在python里头读取

稍后再贴代码