Retrieve mouse coordinate in matplotlib from image plot (not figure)

Question

I want to print out the mouse coordinate upon clicking on the displayed image. It is not a graph figure.

After looking through all online forum, I discovered they are all made for a graph figure and not displayed images. I'm surprised I couldn't find even one example.

import matplotlib.pyplot as plt
import matplotlib.image as mpimg

# The usual way which I found online
fig = plt.figure() 
ax = fig.add_subplot(111) 
ax.plot(np.random.rand(10)) 

def onclick(event): 
     print("button=%d, x=%d, y=%d, xdata=%f, ydata=%f" %( 
         event.button, event.x, event.y, event.xdata, event.ydata)) 

cid = fig.canvas.mpl_connect('button_press_event', onclick) 

# What I currently Have
img = mpimg.imread("my_img.jpg")
plt.imshow(img)

plt.show()

Are you looking to find the mouse coordinate relative to your screen or image? — Axois
– Axois, Commented Aug 2, 2019 at 2:00
If you are looking to get coordinates from image you can also try the trackpy module that does this. — Drees
– Drees, Commented Aug 2, 2019 at 2:01
Axios, it is relative to the image. It is actually displayed on the bottom right corner, I just need to have in my python code. — 5Volts
– 5Volts, Commented Aug 2, 2019 at 2:37

furas · Accepted Answer · 2019-08-02 03:43:52Z

2

Matplot uses the same methods to display plot or image. You have to only find figure for displayed image.

import matplotlib.pyplot as plt
import matplotlib.image as mpimg

def onclick(event): 
    print("button=%d, x=%d, y=%d, xdata=%f, ydata=%f" % ( 
         event.button, event.x, event.y, event.xdata, event.ydata)) 

img = mpimg.imread("image.jpg")
ax = plt.imshow(img)
fig = ax.get_figure()
cid = fig.canvas.mpl_connect('button_press_event', onclick) 

plt.show()

Instead of mpimg.imread() you can use plt.imread()

answered Aug 2, 2019 at 3:43

furas

149k12 gold badges121 silver badges171 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Retrieve mouse coordinate in matplotlib from image plot (not figure)

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related