Mouse callback function:
def setMouseCallback( windowName, #Window name onMouse, # Mouse response handler param=None) #The processing function of theID
eventThe mouse event:
event： EVENT_LBUTTONDBLCLK = 7 Double left click EVENT_LBUTTONDOWN = 1 left click EVENT_LBUTTONUP = 4 Left click to release EVENT_MBUTTONDBLCLK = 9 Intermediate release EVENT_MBUTTONDOWN = 3 Middle click EVENT_MBUTTONUP = 6 Intermediate release EVENT_MOUSEHWHEEL = 11 Rolling Wheel Events EVENT_MOUSEMOVE = 0 sliding movement EVENT_MOUSEWHEEL = 10 Rolling Wheel Events EVENT_RBUTTONDBLCLK = 8 right-click and double-click EVENT_RBUTTONDOWN = 2 right click EVENT_RBUTTONUP = 5 Right click release flags: EVENT_FLAG_ALTKEY = 32 check or refer toAltincidents of non-release EVENT_FLAG_CTRLKEY = 8 check or refer toCtrlincidents of non-release EVENT_FLAG_LBUTTON = 1 Left-click Drag and Drop EVENT_FLAG_MBUTTON = 4 middle-button drag and drop (computing) EVENT_FLAG_RBUTTON = 2 Right-click drag and drop EVENT_FLAG_SHIFTKEY = 16 check or refer toShiftincidents of non-release
typical example
Draw a rectangle on the image by dragging with the left mouse click and output the rectangle information:
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)
(img, (ix, iy), (x, y), (0, 255, 0), 2)
img = ("") #Load the picture
('image')
('image', draw_rectangle)
while(1):
('image', img)
if (20) & 0xFF == 27:
break
()
Output:
point1:= 254 64 point2:= 708 569 width= 454 height= 505
Above this opencv3/python mouse response operation in detail is all I have shared with you, I hope to give you a reference, and I hope you support me more.