参考： [FFmpeg生成的MP3文件在OS X上时长不对](https://blog.shengbin.me/posts/ffmpeg-creates-mp3-file-with-wrong-duration-on-os-x) [解决ffmpeg生成mp3在ios上时长不对的问题](https://blog.sharpbai.com/2017/03/%E8%A7%A3%E5%86%B3ffmpeg%E7%94%9F%E6%88%90mp3%E5%9C%A8ios%E4%B8%8A%E6%97%B6%E9%95%BF%E4%B8%8D%E5%AF%B9%E7%9A%84%E9%97%AE%E9%A2%98/)
