OpenCV：播放使用 ffmpeg 和 concat 创建的视频时出现问题

Question

我使用以下方式连接了几个视频：

$ ffmpeg -f concat -safe 0 -i list_files.txt -c copy total.mp4

其中 list_files.txt 就像：

file 'file1.mp4'
file 'file2.mp4'

不幸的是，如果我用 opencv 播放它：

import cv2
import numpy as np

# Create a VideoCapture object and read from input file
# If the input is the camera, pass 0 instead of the video file name
cap = cv2.VideoCapture('../Video_outputs/010_introduction.mp4')

# Check if camera opened successfully
if (cap.isOpened()== False): 
  print("Error opening video stream or file")

# Read until video is completed
while(cap.isOpened()):
  # Capture frame-by-frame
  ret, frame = cap.read()
  if ret == True:

    # Display the resulting frame
    cv2.imshow('Frame',frame)

    # Press Q on keyboard to  exit
    if cv2.waitKey(24) & 0xFF == ord('q'):
      break

  # Break the loop
  else: 
    break

# When everything done, release the video capture object
cap.release()

# Closes all the frames
cv2.destroyAllWindows()

第一个视频播放正常，但下一个连接的视频看起来很难看：

我是否遗漏了某些内容，或者是向上游报告的错误？

PS：我正在使用这段代码：

import cv2
import numpy as np

# Create a VideoCapture object and read from input file
# If the input is the camera, pass 0 instead of the video file name
cap = cv2.VideoCapture('../Video_outputs/010_introduction.mp4')

# Check if camera opened successfully
if (cap.isOpened()== False): 
  print("Error opening video stream or file")

# Read until video is completed
while(cap.isOpened()):
  # Capture frame-by-frame
  ret, frame = cap.read()
  if ret == True:

    # Display the resulting frame
    cv2.imshow('Frame',frame)

    # Press Q on keyboard to  exit
    if cv2.waitKey(24) & 0xFF == ord('q'):
      break

  # Break the loop
  else: 
    break

# When everything done, release the video capture object
cap.release()

# Closes all the frames
cv2.destroyAllWindows()