display images inside a loop by overwriting the existing plot/figure in python

Question

I have hundreds of thousands of images which I have to get from URL, see them ,tag them and then save them in their respective category as spam or non spam. On top of that, I'll be working with google which makes it impossible. My idea is that instead of looking at each image by opening, analysing, renaming and then saving them in directory, I just get the image from url, see within a loop, input a single word and based on that input, my function will save them in their respective directories.

I tried doing

from PIL import Image
import numpy as np
import matplotlib.pyplot as plt
from IPython.display import Image

fg = plt.figure()
for i in range(5):
  plt.imshow(np.random.rand(50,50))
  plt.show()
  x = input()
  print(x)

but instead of overwriting the existing frame, it is plotting a different figure. I have even used 1,1 subplot inside a loop but it is not working. Ipython's method does not even display inside a loop either. Could somebody please help me with this problem.

Sameeresque · Accepted Answer · 2020-07-10 03:44:52Z

2

You can make use of matplotlib's interactive mode by invoking plt.ion(). An example:

import numpy as np
import matplotlib.pyplot as plt
%matplotlib notebook
fig, ax = plt.subplots()

plt.ion()
plt.show()
for i in range(5): 
    ax.imshow(np.random.rand(50,50))  # plot the figure
    plt.gcf().canvas.draw()
    yorn = input("Press 1 to continue, 0 to break") 
    if yorn==0:
        break

Expected output:

edited Jul 10, 2020 at 3:44

answered Jul 9, 2020 at 22:38

Sameeresque

2,6022 gold badges14 silver badges24 bronze badges

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

5 Comments

Deshwal Over a year ago

Have you tried the code? Actuallt it is not even showing any output image

Sameeresque Over a year ago

See the expected output.

Deshwal Over a year ago

not working in my case. Could it be because of colab?

Abang F. Over a year ago

This works for me (but in the example above you should have yorn == '0' instead of yorn == 0). Also, if you have hundreds of images doing this in jupyter notebook will soon make the image not visible (you have to scroll up). I recommend making a python script and running it from the command prompt, so the image is shown in a new window.

Sameeresque Over a year ago

If you are using Google Colab, you might fight this SO useful.

Collectives™ on Stack Overflow

display images inside a loop by overwriting the existing plot/figure in python

1 Answer 1

5 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

5 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related