python-3.x - 在OpenCV中播放电影

Question

尝试播放电影时出现以下错误:

cv2.imshow("Video Output", frames)
TypeError: Expected Ptr<cv::UMat> for argument 'mat'

注释掉的行是我解决此问题的尝试，但是仍然出现错误。
我究竟做错了什么？

import cv2
import numpy as np

vid = cv2.VideoCapture("resources/Plaza.mp4")
while True:
    frames = vid.read()
    # frames = cv2.cvtColor(frames, cv2.COLOR_RGB2BGR)
    # frames_arr = np.array(frames)
    cv2.imshow("Video Output", frames)
    if cv2.waitKey(1) & 0xFF == ord('q'):
        break

Answer 1

更好的实现是:

检查视频是否使用vid.isOpened()打开

vid = cv2.VideoCapture("resources/Plaza.mp4")
while vid.isOpened():

如果成功返回框架，则显示它。

ret, frames = vid.read()

if ret:
    # frames = cv2.cvtColor(frames, cv2.COLOR_RGB2BGR)
    # frames_arr = np.array(frames)
    cv2.imshow("Video Output", frames)
    if cv2.waitKey(1) & 0xFF == ord('q'):
        break

确保始终关闭所有窗口并释放VideoCapture对象

cv2.destoyAllWindows()
vid.release()

码:

import cv2
import numpy as np

vid = cv2.VideoCapture("resources/Plaza.mp4")
while vid.isOpened():
    ret, frames = vid.read()

    if ret:
        # frames = cv2.cvtColor(frames, cv2.COLOR_RGB2BGR)
        # frames_arr = np.array(frames)
        cv2.imshow("Video Output", frames)
        if cv2.waitKey(1) & 0xFF == ord('q'):
            break
    else
        # continue with the next frame
        continue

cv2.destoyAllWindows()
vid.release()