python opencv3 视频文件的读写

git： https://github.com/linyi0604/Computer-Vision

 # coding:utf8
 import cv2

 """
 读取视频文件的帧， 采用yuv颜色编码写入到另一个帧

 VideoCapture和VideoWriter用于视频文件的读写
 VideoCapture读的每一帧都是一个bgr格式的图像
 """
 videoCapture = cv2.VideoCapture("../data/demo3.mp4")
 fps = videoCapture.get(cv2.CAP_PROP_FPS)
 size = (
     int(videoCapture.get(cv2.CAP_PROP_FRAME_WIDTH)),
     int(videoCapture.get(cv2.CAP_PROP_FRAME_HEIGHT))
 )

 videoWriter = cv2.VideoWriter(
     "output.mp4",
     cv2.VideoWriter_fourcc("I", "", "", ""),  # 编码器
     fps,
     size
 )
 '''
 编码器常用的几种：
 cv2.VideoWriter_fourcc("I", "4", "2", "0")
     压缩的yuv颜色编码器，4:2:0色彩度子采样 兼容性好，产生很大的视频 avi
 cv2.VideoWriter_fourcc("P", I", "M", "1")
     采用mpeg-1编码，文件为avi
 cv2.VideoWriter_fourcc("X", "V", "T", "D")
     采用mpeg-4编码，得到视频大小平均 拓展名avi
 cv2.VideoWriter_fourcc("T", "H", "E", "O")
     Ogg Vorbis， 拓展名为ogv
 cv2.VideoWriter_fourcc("F", "L", "V", "1")
     FLASH视频，拓展名为.flv
 '''

 success, frame = videoCapture.read()
 while success:  # 循环直到没有帧了
     videoWriter.write(frame)
     success, frame = videoCapture.read()