[FFmpeg-user] Duration of source video and substracted audio different

[张鹏程]

Hi!
    The duration of source video and substracted wav audio is different , why?
    I'm recorgnizing subtitle from audio, and I need to add subtitle back to video. So I want the duration of audio and video the same.
    I run command "ffmpeg -i http://cdn.live.360.cn/huikan_news/vod-media/_XW_203286B417B7C6466B3B_20160627185953.m3u8 -vntest.wav -y?"
    I paste my CLI here, http://pastebin.com/iwDFv6zC

    Thanks a lot!