import cv2


def clip_video(source_video, target_video, start_time, end_time):
  cap = cv2.VideoCapture(source_video)
  if not cap.isOpened():
    logger_warning('video is not opened')
  else:
    success, frame = cap.read()
    f_shape = frame.shape
    f_height = f_shape[0] # 原视频图片的高度
    f_width = f_shape[1]
    fps = cap.get(5) # 帧速率
    frame_number = cap.get(7) # 视频文件的帧数
    duration = frame_number / fps # 视频总帧数/帧速率 是时间/秒【总共有多少秒的视频时间】
    if start_time > duration or end_time > duration:
      return
    start_time = fps * float(start_time)
    end_time = fps * float(end_time)
    # AVI格式编码输出 XVID
    four_cc = cv2.VideoWriter_fourcc(*'H264')
    video_writer = cv2.VideoWriter(target_video, four_cc, fps, (int(f_width), int(f_height)))
    num = 0
    while True:
      success, frame = cap.read()
      if int(start_time) <= int(num) <= int(end_time):
        if success:
          video_writer.write(frame)
        else:
          break
      num += 1
      if num > frame_number:
        break
    cap.release()