如何在和cv2.VideoCapture()中使用多线程？

import cv2
import threading

class VideoCaptureThread(threading.Thread):
    def __init__(self, video_path):
        threading.Thread.__init__(self)
        self.video_path = video_path
        self.frame = None
        self.is_running = False

    def run(self):
        self.is_running = True
        cap = cv2.VideoCapture(self.video_path)
        while self.is_running:
            ret, frame = cap.read()
            if ret:
                self.frame = frame
            else:
                break
        cap.release()

    def stop(self):
        self.is_running = False

# 创建VideoCaptureThread对象并启动线程
video_thread = VideoCaptureThread("video.mp4")
video_thread.start()

# 主线程中使用视频帧
while True:
    if video_thread.frame is not None:
        frame = video_thread.frame
        # 进行视频帧的处理
        # ...

# 停止视频线程
video_thread.stop()
video_thread.join()