ffmpeg tips

ffmpeg 从视频中提取音频文件保存为MP3

ffmpeg -i apple.mp4 -f mp3 -vn apple.mp3

ffmpeg 从视频中提取音频文件，修改播放速度

ffmpeg -i apple.mp4 -filter:a "atempo=1.3" -f mp3 -vn apple.mp3

注意：

• 倍率调整范围为[0.5, 2.0]

#coding:utf-8
#description: MP42mp3

import os,sys
import argparse
import subprocess

def convert(path):
    bin = "ffmpeg.exe"
    ls = os.listdir(path)
    for x in ls:
        if x.endswith("mp4"):
            cmdargs = '%s -i "%s" -filter:a "atempo=1.3" -f mp3 -vn "%s"' % (bin ,x,x.replace(".mp4",".mp3"))
            print cmdargs

if __name__ =="__main__":
    if ( os.path.isdir(sys.argv[1])):
        path = sys.argv[1]
        convert(path)

参考链接：https://blog.csdn.net/matrix_laboratory/article/details/53158307