“with”关键字不适用于python中的“cv2.VideoCapture(0)”

Question

code:

import cv2
import numpy as np

with cv2.VideoCapture(0) as cap:
    while True:
        ret, frame = cap.read()
        cv2.imshow("Title", frame)

        if cv2.waitKey(1):
            break

        cv2.destroyAllWindows()`

Throws error: " Traceback (most recent call last): File "D:/Python/openCV/Basic_Video/Basic.py", line 4, in with cv2.VideoCapture(0) as cap: AttributeError: __enter__ "

Answer 1

The with keyword is not supported for VideoCapture . All examples that I found always declare it first:

How to process images of a video, frame by frame in video streaming using Opencv python

https://opencv-python-tutroals.readthedocs.io/en/latest/py_tutorials/py_gui/py_video_display/py_video_display.html

cv2.videocapture.read() does not return a numpy array