opencv之 读取视频的帧数变成图片

from cv2 import cv2
video = cv2.VideoCapture("./video/test.mp4")  # 获取一个视频来打开
isOpened = video.isOpened   #  判断这个视频是否可以正常打开
print(isOpened)
fps = video.get(cv2.CAP_PROP_FPS)   #  读取这个视频的帧率
width = int(video.get(cv2.CAP_PROP_FRAME_WIDTH))   # 获取视频的宽度
height = int(video.get(cv2.CAP_PROP_FRAME_HEIGHT))  #   获取视频的高度
print(fps, width, height)  # 查看帧率 宽高
i = 0
while isOpened:
    if i == 10:
        break
    else:
        i += 1
    (flag, frame) = video.read()  # 读取每一张图片  flag 表明是否都区成功， frame表示图片的内容
    fileName = "image" + str(i) + ".jpg"
    print(fileName)
    if flag == True:
        print("./pic/"+fileName)
        cv2.imwrite("./pic/"+fileName, frame, [cv2.IMWRITE_JPEG_QUALITY, 100])
print("end!")