cv2.rectangle

cv2.rectangle()

void cv::rectangle	(	InputOutputArray 	img,
Point 	pt1,
Point 	pt2,
const Scalar & 	color,
int 	thickness = 1,
int 	lineType = LINE_8,
int 	shift = 0 
)		
Python:
img	=	cv.rectangle(	img, pt1, pt2, color[, thickness[, lineType[, shift]]]	)
img	=	cv.rectangle(	img, rec, color[, thickness[, lineType[, shift]]]	)

In [1]: import cv2
In [2]: import numpy as np
In [3]: img=np.zeros((512,512,3),np.uint8)
In [4]: cv2.rectangle(img,(300,0),(410,128),(0,255,0),3)
In [5]: winname = 'example'
   ...: cv2.namedWindow(winname)
   ...: cv2.imshow(winname, img)
   ...: cv2.waitKey(0)
   ...: cv2.destroyWindow(winname)

类似cv2.line()、cv2.circle()、cv2.ellipse()、cv2.putText()等都是这么画的，只不过cv2.rectangle()用的比较多一些，还有cv2.polylines()。

void cv::polylines	(	InputOutputArray 	img,
InputArrayOfArrays 	pts,
bool 	isClosed, # 闭环
const Scalar & 	color,
int 	thickness = 1,
int 	lineType = LINE_8,
int 	shift = 0 
)		
Python:
img	=	cv.polylines(	img, pts, isClosed, color[, thickness[, lineType[, shift]]]	)

pts = np.array([[10,5],[20,30],[70,20],[50,10]], np.int32)
pts = pts.reshape((-1,1,2))
cv.polylines(img,[pts],True,(0,255,255))

 

font = cv.FONT_HERSHEY_SIMPLEX
cv.putText(img,'OpenCV',(10,500), font, 4,(255,255,255),2,cv.LINE_AA)

 

# 要画圆的话，只需要指定圆形的中心点坐标和半径大小。

我们在上面的矩形中画一个圆。


cv.circle(img,(447,63), 63, (0,0,255), -1)

 

cv.ellipse(img,(256,256),(100,50),0,0,180,255,-1)