0. 安装-Debian Jessie 用户安装：
Debian8.9亲测有效：
1.编辑/etc/apt/sources.list加入

deb http://www.deb-multimedia.org jessie main

2.然后执行一下命令即可

sudo apt-get update
sudo apt-get install deb-multimedia-keyring
sudo apt-get install ffmpeg

3.参考文档
https://linux.cn/article-3035-1.html
https://www.cmsky.com/debian-install-ffmpeg/

1.安装微信语音转码：silk-v3-decoder

    https://github.com/kn007/silk-v3-decoder

2.百度ai语音识别:

原始 PCM 的录音参数必须符合：单声道、 8k/16k 采样率、16bit 位深，
支持的格式有：pcm（不压缩）、wav（不压缩，pcm编码）、amr（压缩格式）。

“单通道，16位，16000/8000”各指的是channels、   bit rate/sample size    和sample rate
-ac channels、   -b:a bitrate、   -ar rate
-ac 1           -b:a 16         -ar 16000

ffmpeg -i laixiao.silk -acodec libmp3lame laixiao.mp3
ffmpeg -i laixiao laixiao.mp3
ffmpeg -i laixiao.mp3 laixiao.amr
ffmpeg -i laixiao.mp3 -ar 16000 -b:a 16 -ac 1 laixiao.amr
ffmpeg -i dd3f23e2869fb1458f9957f770079044.silk -c:a libopencore_amrnb -ac 1 -ar 8000 -b:a 12.20k -y dd3f23e2869fb1458f9957f770079044.amr
ffmpeg -i dd3f23e2869fb1458f9957f770079044.silk -c:a libopencore_amrnb -ac 1 -ar 8000 -b:a 7.95K -y dd3f23e2869fb1458f9957f770079044.amr
ffmpeg -i dd3f23e2869fb1458f9957f770079044 -f s16le -ar 8000 dd3f23e2869fb1458f9957f770079044.mp3
ffmpeg -f s16le -ac 2 -i dd3f23e2869fb1458f9957f770079044.silk -f amr -ar 8000 -ac 1 dd3f23e2869fb1458f9957f770079044.amr
ffmpeg -f s16le -ar 16000 -i laixiao.silk -f amr -ar 16000 -b:a 16 -ac 1 laixiao.amr
ffmpeg -f s16le -ar 12k -i laixiao.silk -f amr -ar 16000 -b:a 16 -ac 1 laixiao.amr

3.执行转码命令
sh converter.sh laixiao.silk mp3
sh converter.sh laixiao.silk wav

ffmpeg -i laixiao.mp3 -ac 1 -b:a 16 -ar 8000 laixiao.amr

4.java代码调用：
http://blog.csdn.net/u010018421/article/details/71280099