Have to import cv2 and pop up window frist, or else it stuck forever

[leemengwei]

@SSacSim Yes One have to import cv2 and pop up window frist. Thats really annoying.

transformers 4.48.3
opencv-python 4.10.0.84

@purusharthmalik

Originally posted by @leemengwei in #37239

[Rocketknight1]

I'm not sure what we can do with this error! Have you tried opening an issue with openCV?

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[Jaykumaran]

Same issue importing transformers in a conda env with cv2 causes to freeze with the first frame indefinitely,

However in the same env cv2.imshow() works when transformers is commented.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the contributing guidelines are likely to be ignored.

[gaschler]

I also ran into this and I can repro this issue.

Versions:
Python 3.10.19
transformers 4.53.2

The following code gets stuck "Try to show image":

import cv2
import numpy as np
from transformers import AutoImageProcessor

image = np.zeros((200, 400))
print("Try to show image")
cv2.imshow("Debug", image)
print("Success")
cv2.waitKey(2000)  # 2 seconds

The following unusual work around is possible:

import cv2
cv2.namedWindow("Debug")
from transformers import AutoImageProcessor
import numpy as np

image = np.zeros((200, 400))
print("Try to show image")
cv2.imshow("Debug", image)
print("Success")
cv2.waitKey(2000)  # 2 seconds

Please re-open, this seems pretty specific to transformers; it does not happen with import torch alone.