Outline of a normal video processing code

normal_cv.py

def process_video():
  cap = cv2.VideoCapture("input_file.mp4")        # Define the input video handler
  out = cv2.VideoWriter("output_file.avi", ...)   # Define the output video handler
  while (cap.isOpened()):                         # Loop through the video frames
    ret, frame = cap.read()                       # Read a frame
    # ... DO SOME STUFF TO frame... #             # Perform some operation
    out.write(frame)                              # Define the input video handler

process_video()                                   # Call the actual function