环境依赖说明:
1、在服务器安装ffmpeg
2、使用ffmpeg -i 命令来转换amr为mp3格式
#php代码
command = "/sbin/ffmpeg -y -i {#amrPath} {#mp3Path} 2>&1";exec(#command, #out, #exitval);
cenos6系统下安装ffmpeg,具体安装步骤如下：
① 首先安装系统编译依赖环境
[root@localhost/]#yum install -y automake autoconf libtool gcc gcc-c++
② 编译所需源码包#yasm：汇编器，新版本的ffmpeg增加了汇编代码
[root@localhost /]#wget /projects/yasm/releases/yasm-1.3.0.tar.gz
[root@localhost /]#tar -xzvf yasm-1.3.0.tar.gz
[root@localhost /]#cd yasm-1.3.0
[root@localhost /]#./configure
[root@localhost /]#make && make install
#lame：Mp3音频解码
[root@localhost /]#wget http://jaist./project/lame/lame/3.99/lame-3.99.5.tar.gz
[root@localhost /]#tar -xzvf lame-3.99.5.tar.gz
[root@localhost /]#cd lame-3.99.5
[root@localhost /]#./configure
[root@localhost /]#make && make install
#amr支持
[root@localhost /]#wget /project/opencore-amr/opencore-amr/opencore-amr-0.1.3.tar.gz
[root@localhost /]#tar -xzvf opencore-amr-0.1.3.tar.gz
[root@localhost /]#cd opencore-amr-0.1.3
[root@localhost /]#./configure
[root@localhost /]#make && make install
#amrnb支持
[root@localhost /]#wget http://www.penguin.cz/~utx/ftp/amr/amrnb-11.0.0.0.tar.bz2
[root@localhost /]#tar -xjvf amrnb-11.0.0.0.tar.bz2
[root@localhost /]#cd amrnb-11.0.0.0
[root@localhost /]#./configure
[root@localhost /]#make && make install
#amrwb支持
[root@localhost /]#wget http://www.penguin.cz/~utx/ftp/amr/amrwb-11.0.0.0.tar.bz2
[root@localhost /]#tar -xjvf amrwb-11.0.0.0.tar.bz2
[root@localhost /]#cd amrwb-11.0.0.0
[root@localhost /]#./configure
[root@localhost /]#make && make install
#ffmpeg
[root@localhost /]#wget /releases/ffmpeg-2.5.3.tar.bz2
[root@localhost /]#tar -xjvf ffmpeg-2.5.3.tar.bz2
[root@localhost /]#cd ffmpeg-2.5.3
[root@localhost /]#./configure --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-version3 --enable-shared
[root@localhost /]#make && make install
#加载配置#最后写入config后，终端运行ffmpeg命令，出现success和已安装的扩展，则运行成功
[root@localhost /]#ldconfig
③ 使用方法
[root@localhost/]#ffmpeg -i 1.mp3 -ac 1 -ar 8000 1.amr #MP3转换AMR
[root@localhost /]#ffmpeg -i 1.amr 1.mp3 #AMR转换MP3
在安装过程中可能出现的错误如下:
错误1. ffmpeg默认安装目录为"/usr/local/lib",有些64位系统下软件目录则为"/usr/lib64"，编译过程中可能会出现
"ffmpeg: error while loading shared libraries: libmp3lame.so.0: cannot open shared object file: No such file or directory"等类似的错误,解决办法是建立软链接:
[root@localhost /]#ln -s /usr/local/lib/libmp3lame.so.0.0.0 /usr/lib64/libmp3lame.so.0
错误2. 如果出现以下提示:ffmpeg: error while loading shared libraries: libavdevice.so.54: cannot open shared object file: No such file or directory 可以通过如下方式查看ffmpeg的动态链接库哪些没有找到：
[root@localhost /]#ldd `which ffmpeg`
[root@localhost /]#libavdevice.so.54 => not found
libavfilter.so.3 => notfound
libavformat.so.54 => notfound
libavcodec.so.54 => notfound
libswresample.so.0=> notfound
libswscale.so.2 => notfound
libavutil.so.51 => notfound
libm.so.6 => /lib64/libm.so.6 (0x00002ab7c0eb6000)
libpthread.so.0=> /lib64/libpthread.so.0 (0x00002ab7c100b000)
libc.so.6 => /lib64/libc.so.6 (0x00002ab7c1125000)/lib64/ld-linux-x86-64.so.2 (0x00002ab7c0d9a000)#如果类似于上面的输出内容，查找以上类库，会发现全部在/usr/local/lib/下
[root@localhost /]#find /usr/local/lib/ | grep -E "libavdevice.so.54|libavfilter.so.3|libavcodec.so.54"
[root@localhost /]#/usr/local/lib/libavfilter.so.3.17.100
/usr/local/lib/libavcodec.so.54.59.100
/usr/local/lib/libavdevice.so.54
/usr/local/lib/libavcodec.so.54
/usr/local/lib/libavfilter.so.3
/usr/local/lib/libavdevice.so.54.2.101
#查看链接库配置文件
[root@localhost /]#more /etc/ld.so.conf | grep /usr/local/lib#如果不包含的话，需要编辑此文添加：
[root@localhost /]#vi /etc/ld.so.conf
[root@localhost /]#/usr/local/lib
[root@localhost /]#/usr/local/lib64#运行配置命令
[root@localhost /]#ldconfig
