4M=512KB/S=4096Kbps 1KB/S=8Kbps8倍速转:http://zhidao.baidu.com/link?url=8GAyhcY9BbVstQr8pE3I7QP_M53Km1zWKitaxT02x-q7iFXNwRVcyUzjwhngf35JVf2fEdReVyuP7IiLikSJRa