新手，参考了以下链接：
python opencv在图像上画矩形（已验证）
本文可以实现在指定图片上动态绘制圆和矩形。
import cv2
import numpy as np
import copy
class Rect(object):
#创建一个类用于接收鼠标点击产生的数据坐标点。
def __init__(self):
self.t1 = (0,0)
self.br = (0,0)
self.r = 0
def regularize(self):
pt1 = (min(self.t1[0],self.br[0]),min(self.t1[1],self.br[1]))
br1 = (max(self.t1[0],self.br[0]),max(self.t1[1],self.br[1]))
self.t1 = pt1
self.br = br1
class DrawRects(object):
def __init__(self,img,color = (0,255,0),thickness = 3):
self.img = img
self.image_for_show = img.copy()
'''
用于覆盖之前的图片，然后在新的空白图片上将以前绘制的图片和目前最新的图片
绘制的到新的图片上。
'''
self.color = color
self.thickness = thickness
self.left_button_down = False #用于判断左键是否按下。
self.current_rect = Rect() #用于接收最新绘制的图形。
self.rects = [] #用于接收绘制的矩形数据。
self.circles = [] #用于接收绘制的圆数据
@staticmethod
def __clip(value,low,high):
output = max(value,low)
output = min(output,high)
return output
def shrink_point(self,x,y):
height,width = self.image_for_show.shape[0:2]
x_shrink = self.__clip(x,0,width)
y_shrink = self.__clip(y,0,height)
return (x_shrink,y_shrink)
'''
上述方法用于限制鼠标点击产生的数据在图片范围内。
'''
def reset_image(self):
self.image_for_show = self.img.copy()
def append(self):
if draw_circle_now:
self.rects.append(['c',copy.deepcopy(self.current_rect)])
else:
self.rects.append(['r',copy.deepcopy(self.current_rect)])
def draw(self):
for rect in self.rects:
if rect[0] == 'r':
cv2.rectangle(self.image_for_show,rect[1].t1,rect[1].br,color = self.color,thickness=self.thickness)
elif rect[0] == 'c':
cv2.circle(self.image_for_show,rect[1].t1,rect[1].r,color = self.color,thickness = self.thickness)
def cal_R(self):
self.current_rect.r = int((abs(self.current_rect.br[0] - self.current_rect.t1[0])**2 + abs(self.current_rect.br[1] - self.current_rect.t1[1])**2)**0.5)
#print(self.current_circle.r)
return self.current_rect.r
def draw_current_rect(self):
if draw_circle_now:
self.current_rect.r = self.cal_R()
cv2.circle(self.image_for_show,self.current_rect.t1,self.current_rect.r,color = self.color,thickness=3)
else:
cv2.rectangle(self.image_for_show,self.current_rect.t1,self.current_rect.br,
color = self.color,thickness = self.thickness)
def pop(self):
rect = Rect()
if self.rects:
rect = self.rects.pop()
return rect
def onmouse_draw_rect(event,x,y,flags,draw_rects):
if event == cv2.EVENT_LBUTTONDOWN:
draw_rects.left_button_down = True
draw_rects.current_rect.t1 = (x,y)
if draw_rects.left_button_down and event == cv2.EVENT_MOUSEMOVE:
draw_rects.current_rect.br = draw_rects.shrink_point(x,y)
draw_rects.reset_image()
draw_rects.draw()
draw_rects.draw_current_rect()
if event == cv2.EVENT_LBUTTONUP:
draw_rects.left_button_down = False
draw_rects.current_rect.br = draw_rects.shrink_point(x,y)
#draw_rects.current_rect.regularize()
draw_rects.append()
if (not draw_rects.left_button_down) and event == cv2.EVENT_RBUTTONDOWN:
draw_rects.pop()
draw_rects.reset_image()
draw_rects.draw()
draw_circle_now = False
img = np.zeros((516,516,3),np.uint8)
draw_rects = DrawRects(img,(0,255,255))
cv2.namedWindow('image')
cv2.setMouseCallback('image',onmouse_draw_rect,draw_rects)
while True:
cv2.imshow('image',draw_rects.image_for_show)
key = cv2.waitKey(30)
if key == ord('c'):
draw_circle_now = not draw_circle_now
elif key == 27:
break
cv2.destroyAllWindows()到此这篇关于Python利用cv2动态绘制圆和矩形的示例详解的文章就介绍到这了,更多相关Python cv2动态绘制圆和矩形内容请搜索编程网以前的文章或继续浏览下面的相关文章希望大家以后多多支持编程网！
