写一个bat mp4转mp3

@echo off setlocal enabledelayedexpansion

set "input_dir=%cd%" set "output_dir=%cd%\mp3"

if not exist "%output_dir%" mkdir "%output_dir%"

for %%a in ("%input_dir%*.mp4") do ( ffmpeg -i "%%a" -vn -acodec libmp3lame -b:a 128k -f mp3 "%output_dir%%%~na.mp3" )

echo Conversion complete. pause exit