OpenCV USB 摄像头不适用于 Raspberry Pi 4 32 位

Question

当我尝试使用 opencv 和 python 开始视频采集时，它根本无法加载。不显示任何问题，不返回任何内容。没什么！！！

代码是最简单的：

import cv2
import sys

video_capture = cv2.VideoCapture(0)

while True:
   ret, frame = video_capture.read()

   cv2.imshow('Video', frame)

   if cv2.waitKey(1) & 0xFF == ord('q'):
       break

video_capture.release()
cv2.destroyAllWindows()

这是运行这个程序的结果

如果我逐行运行代码，这就是卡住的地方

如果我在执行最后一行时按 Ctrl+C，它会告诉我：

Trying to dispose element pipeline0, but it is in PAUSED instead of the NULL state.

You need to explicitly set elements to the NULL state before

dropping the final reference, to allow them to clean up.

This problem may also be caused by a refcounting bug in the

application or some element.

Answer 1

也许不是一个真正的解决方案，但可以尝试像这样指定视频后端：

video_capture = cv2.VideoCapture(0, CAP_V4L2)