Python 2.7 Opencv：检测鼠标在图片上单击的位置

我有一段代码，其中我使用OpenCV简单地显示了一幅图像：

    import numpy as np 
    import cv2

    class LoadImage:
        def loadImage(self):
            self.img=cv2.imread('photo.png')
            cv2.imshow('Test',self.img)

            self.pressedkey=cv2.waitKey(0)

            # Wait for ESC key to exit
            if self.pressedkey==27:
                cv2.destroyAllWindows()

    # Start of the main program here        
    if __name__=="__main__":
        LI=LoadImage()
        LI.loadImage()

---

当窗口显示有照片时，我想在控制台（终端）上显示鼠标单击图片时的位置。我不知道该怎么做。有什么帮助吗？

这里是一个鼠标回调函数示例，它捕获了左键双击

def draw_circle(event,x,y,flags,param):
    global mouseX,mouseY
    if event == cv2.EVENT_LBUTTONDBLCLK:
        cv2.circle(img,(x,y),100,(255,0,0),-1)
        mouseX,mouseY = x,y

然后需要将该函数绑定到一个窗口，该窗口将捕获鼠标单击

img = np.zeros((512,512,3), np.uint8)
cv2.namedWindow('image')
cv2.setMouseCallback('image',draw_circle)

然后，在一个无限处理循环中（或任何您想要的）

此代码的作用是什么？

每当您在黑色窗口内双击并按下将创建的a键时，它将鼠标位置存储在全局变量

mouseX

&

mouseY

elif k == ord('a'):
    print mouseX,mouseY

将在每次按下a按钮时打印当前存储的鼠标单击位置

---

---

下面的代码“借用”是我的实现：

无需存储点击位置，只需显示：

def onMouse(event, x, y, flags, param):
    if event == cv2.EVENT_LBUTTONDOWN:
       # draw circle here (etc...)
       print('x = %d, y = %d'%(x, y))
cv2.setMouseCallback('WindowName', onMouse)

如果要使用代码中其他位置的位置，可以使用以下方法获取坐标：

posList = []
def onMouse(event, x, y, flags, param):
   global posList
   if event == cv2.EVENT_LBUTTONDOWN:
        posList.append((x, y))
cv2.setMouseCallback('WindowName', onMouse)
posNp = np.array(posList)     # convert to NumPy for later use

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我已经将PyIgnition库从Pygame移植到opencv2。在以下位置查找代码：

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还有几个关于如何使用Python粒子引擎的示例。

您可以通过执行各种鼠标单击事件来检测鼠标在图片上的位置

import cv2

cv2.imshow("image", img)
cv2.namedWindow('image')
cv2.setMouseCallback('image', on_click)

def on_click(event, x, y, p1, p2):
    if event == cv2.EVENT_LBUTTONDOWN:
        cv2.circle(lastImage, (x, y), 3, (255, 0, 0), -1)

在执行鼠标单击事件时，您只需记住一件事，即无论您在哪里使用cv2.imshow或cv2.namedWindow

我在下面的stackoverflow文章中给出了使用python 3.x和opencv的工作代码：

您可以参考上面的链接以获得更好的解释

代码：

import cv2
import numpy as np

#This will display all the available mouse click events  
events = [i for i in dir(cv2) if 'EVENT' in i]
print(events)

#This variable we use to store the pixel location
refPt = []

#click event function
def click_event(event, x, y, flags, param):
    if event == cv2.EVENT_LBUTTONDOWN:
        print(x,",",y)
        refPt.append([x,y])
        font = cv2.FONT_HERSHEY_SIMPLEX
        strXY = str(x)+", "+str(y)
        cv2.putText(img, strXY, (x,y), font, 0.5, (255,255,0), 2)
        cv2.imshow("image", img)

    if event == cv2.EVENT_RBUTTONDOWN:
        blue = img[y, x, 0]
        green = img[y, x, 1]
        red = img[y, x, 2]
        font = cv2.FONT_HERSHEY_SIMPLEX
        strBGR = str(blue)+", "+str(green)+","+str(red)
        cv2.putText(img, strBGR, (x,y), font, 0.5, (0,255,255), 2)
        cv2.imshow("image", img)


#Here, you need to change the image name and it's path according to your directory
img = cv2.imread("D:/pictures/abc.jpg")
cv2.imshow("image", img)

#calling the mouse click event
cv2.setMouseCallback("image", click_event)

cv2.waitKey(0)
cv2.destroyAllWindows()

---

下面是OpenCV鼠标回调的基于类的实现，用于获取图像上的点

import cv2
import numpy as np
#events = [i for i in dir(cv2) if 'EVENT' in i]
#print (events)

class MousePts:
    def __init__(self,windowname,img):
        self.windowname = windowname
        self.img1 = img.copy()
        self.img = self.img1.copy()
        cv2.namedWindow(windowname,cv2.WINDOW_NORMAL)
        cv2.imshow(windowname,img)
        self.curr_pt = []
        self.point   = []

    def select_point(self,event,x,y,flags,param):
        if event == cv2.EVENT_LBUTTONDOWN:
            self.point.append([x,y])
            #print(self.point)
            cv2.circle(self.img,(x,y),5,(0,255,0),-1)
        elif event == cv2.EVENT_MOUSEMOVE:
            self.curr_pt = [x,y]
            #print(self.point)

    def getpt(self,count=1,img=None):
        if img is not None:
            self.img = img
        else:
            self.img = self.img1.copy()
        cv2.namedWindow(self.windowname,cv2.WINDOW_NORMAL)
        cv2.imshow(self.windowname,self.img)
        cv2.setMouseCallback(self.windowname,self.select_point)
        self.point = []
        while(1):
            cv2.imshow(self.windowname,self.img)
            k = cv2.waitKey(20) & 0xFF
            if k == 27 or len(self.point)>=count:
                break
            #print(self.point)
        cv2.setMouseCallback(self.windowname, lambda *args : None)
        #cv2.destroyAllWindows()
        return self.point, self.img

if __name__=='__main__':
    img = np.zeros((512,512,3), np.uint8)
    windowname = 'image'
    coordinateStore = MousePts(windowname,img)

    pts,img = coordinateStore.getpt(3)
    print(pts)

    pts,img = coordinateStore.getpt(3,img)
    print(pts)

    cv2.imshow(windowname,img)
    cv2.waitKey(0)

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如果您想在Python 3中通过将鼠标悬停在图像上获得坐标，可以尝试以下方法：

import numpy as np
import cv2 as cv
import os
import sys

# Reduce the size of image by this number to show completely in screen
descalingFactor = 2

# mouse callback function, which will print the coordinates in console
def print_coord(event,x,y,flags,param):
    if event == cv.EVENT_MOUSEMOVE:
        print(f'{x*descalingFactor, y*descalingFactor}\r', end="")

img = cv.imread(cv.samples.findFile('TestImage.png'))
imgheight, imgwidth = img.shape[:2]
resizedImg = cv.resize(img,(int(imgwidth/descalingFactor), int(imgheight/descalingFactor)), interpolation = cv.INTER_AREA)
cv.namedWindow('Get Coordinates')
cv.setMouseCallback('Get Coordinates',print_coord)
cv.imshow('Get Coordinates',resizedImg)
cv.waitKey(0)

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昨天你问了，现在你不知道如何实现鼠标处理程序？@berak这不是同一个问题，我是python和OpenCVI的初学者，再去那里，打印出所有的值，请参阅..@MasoudPourbozorg按escape键还有@MasoudPourbozorg我提供了一个指向我获取代码的源代码的链接，因为它为我的答案提供了更多的额外细节，以及原始代码作者的归属，以及任何潜在的许可问题等细节。@GPPK感谢提供链接，但我很抱歉无法打开它。因此，我建议更新链接或将其全部删除。请检查源代码链接。在第一个代码块的

global mouseX行中，mouseY

您可能还需要添加

img

。否则您将无法将其传递给cv2.circle（img，（x，y），100，（255,0,0），-1）这非常有用。建议编辑：如果双击图像，然后按字母

a

，系统将打印鼠标坐标。欢迎使用。请你解释一下为什么这是除了你分享的代码之外的答案。

import numpy as np
import cv2 as cv
import os
import sys

# Reduce the size of image by this number to show completely in screen
descalingFactor = 2

# mouse callback function, which will print the coordinates in console
def print_coord(event,x,y,flags,param):
    if event == cv.EVENT_MOUSEMOVE:
        print(f'{x*descalingFactor, y*descalingFactor}\r', end="")

img = cv.imread(cv.samples.findFile('TestImage.png'))
imgheight, imgwidth = img.shape[:2]
resizedImg = cv.resize(img,(int(imgwidth/descalingFactor), int(imgheight/descalingFactor)), interpolation = cv.INTER_AREA)
cv.namedWindow('Get Coordinates')
cv.setMouseCallback('Get Coordinates',print_coord)
cv.imshow('Get Coordinates',resizedImg)
cv.waitKey(0)