OpenCV|opencv3/python 鼠标响应操作鼠标响应操作|python|opencv

鼠标回调函数：

def setMouseCallback( windowName,#窗口名称 onMouse,#鼠标响应处理函数 param=None)#处理函数的ID

event鼠标事件:

event： EVENT_LBUTTONDBLCLK = 7左键双击 EVENT_LBUTTONDOWN = 1左键点击 EVENT_LBUTTONUP = 4左键释放 EVENT_MBUTTONDBLCLK = 9中间释放 EVENT_MBUTTONDOWN = 3中间点击 EVENT_MBUTTONUP = 6中间释放 EVENT_MOUSEHWHEEL = 11滚轮事件 EVENT_MOUSEMOVE = 0滑动 EVENT_MOUSEWHEEL = 10滚轮事件 EVENT_RBUTTONDBLCLK = 8右键双击 EVENT_RBUTTONDOWN = 2右键点击 EVENT_RBUTTONUP = 5右键释放flags: EVENT_FLAG_ALTKEY = 32按Alt不放事件 EVENT_FLAG_CTRLKEY = 8按Ctrl不放事件 EVENT_FLAG_LBUTTON = 1左键拖拽 EVENT_FLAG_MBUTTON = 4中键拖拽 EVENT_FLAG_RBUTTON = 2右键拖拽 EVENT_FLAG_SHIFTKEY = 16按Shift不放事件

示例
在图像上用鼠标点击左键拖拽画一矩形，并输出矩形信息：

import cv2 def draw_rectangle(event,x,y,flags,param): global ix, iy if event==cv2.EVENT_LBUTTONDOWN: ix, iy = x, y print("point1:=", x, y) elif event==cv2.EVENT_LBUTTONUP: print("point2:=", x, y) print("width=",x-ix) print("height=", y - iy) cv2.rectangle(img, (ix, iy), (x, y), (0, 255, 0), 2)img = cv2.imread("max.png")#加载图片 cv2.namedWindow('image') cv2.setMouseCallback('image', draw_rectangle) while(1): cv2.imshow('image', img) if cv2.waitKey(20) & 0xFF == 27: break cv2.destroyAllWindows()

【OpenCV|opencv3/python 鼠标响应操作】输出：