我用cv2把多张图片转成视频时候，遇见了这个错误，不能生成视频文件，查了很多资料，最终同时找到了两种解决方案。

代码：

# coding=utf-8
import os
import cv2
from PIL import Image

def makevideo(path, fps):
    """ 将图片合成视频. path: 视频路径，fps: 帧率 """
    fourcc = cv2.VideoWriter_fourcc(*"MJPG")
    path1 = 'C:/Users/lenovo/PycharmProjects/Dataset/gameData/test'
    im = Image.open('C:/Users/lenovo/PycharmProjects/Dataset/gameData/test/10561.jpg')
    print(im.size)
    vw = cv2.VideoWriter(path, fourcc, fps, im.size)
    for i in os.listdir(path1):
        frame = cv2.imread(path1 +'/'+ i)
        vw.write(frame)

if __name__ == '__main__':
    video_path = 'C:/Users/lenovo/PycharmProjects/Dataset/gameData/test_new1.mp4'
    makevideo(video_path, 10)  # 图片转视频

报错信息：

OpenCV: FFMPEG: tag 0x47504a4d/'MJPG' is not supported with codec id 7 and format 'mp4 / MP4 (MPEG-4 Part 14)'
OpenCV: FFMPEG: fallback to use tag 0x7634706d/'mp4v'

解决方法：

1,将fourcc = cv2.VideoWriter_fourcc(*"MJPG")的"MJPG"改成"mp4v"

2,将vw = cv2.VideoWriter(path, fourcc, fps, im.size)的fourcc直接改成 0x00000021

第二种方法虽然会出现OpenCV: FFMPEG: tag 0x00000021/'!???' is not found (format 'mp4 / MP4 (MPEG-4 Part 14)')'，但是生成的视频文件是正常的。

参考链接：https://devtalk.nvidia.com/default/topic/1029451/jetson-tx2/-python-what-is-the-four-characters-fourcc-code-for-mp4-encoding-on-tx2/