linux 下载及安装ffmpeg
java项目在压缩视频的时候使用了ffmpeg.exe,在windows系统下可以使用，发布到linux后无法直接调用ffmpeg.exe文件，需要在linux系统下安装ffmpeg。现总结如下：
1线上下载 及解压
wget http://www.ffmpeg.org/releases/ffmpeg-4.3.1.tar.gz tar -zxvf ffmpeg-4.3.1.tar.gz
2、 进入解压后目录,输入如下命令/usr/local/ffmpeg为自己指定的安装目录.然后安装.如果出现错误，请看最后备注。
cd ffmpeg-4.3.1 ./configure --prefix=/usr/local/ffmpeg make && make install
注意：最后的安装时候需要很长时间，以及出现多个警告warning。没关系，等待即可。
3、配置环境变量(进入vi环境)
vi /etc/profile 然后一直按enter键往下走走到最后 在最后unset i后面添加环境变量（输入:i然后回车进入编辑模式）： export PATH=$PATH:/usr/local/ffmpeg/bin 回车 保存退出（:wq） 查看是否生效 source /ect/profile 设置生效
效果如下：
if [ $UID -gt 199 ] && [ "`/usr/bin/id -gn`" = "`/usr/bin/id -un`" ]; then
umask 002
else
umask 022
fi
for i in /etc/profile.d/*.sh ; do
if [ -r "$i" ]; then
if [ "${-#*i}" != "$-" ]; then
. "$i"
else
. "$i" >/dev/null
fi
fi
done
unset i
export PATH=$PATH:/usr/local/ffmpeg/bin
"/etc/profile" 79L, 1876C written
[root@izm5e7giopzqoxm6ejeva8z ~]# source
-bash: source: filename argument required
source: usage: source filename [arguments]
[root@izm5e7giopzqoxm6ejeva8z ~]# source /etc/profile
[root@izm5e7giopzqoxm6ejeva8z ~]# ffmpeg
ffmpeg version 4.3.1 Copyright (c) 2000-2020 the FFmpeg developers
built with gcc 4.8.5 (GCC) 20150623 (Red Hat 4.8.5-36)
configuration: --prefix=/usr/local/ffmpeg
libavutil 56. 51.100 / 56. 51.100
libavcodec 58. 91.100 / 58. 91.100
libavformat 58. 45.100 / 58. 45.100
libavdevice 58. 10.100 / 58. 10.100
libavfilter 7. 85.100 / 7. 85.100
libswscale 5. 7.100 / 5. 7.100
libswresample 3. 7.100 / 3. 7.100
Hyper fast Audio and Video encoder
usage: ffmpeg [options] [[infile options] -i infile]... {[outfile options] outfile}...
Use -h to get full help or, even better, run 'man ffmpeg'
[root@izm5e7giopzqoxm6ejeva8z ~]# ffmpeg -version
ffmpeg version 4.3.1 Copyright (c) 2000-2020 the FFmpeg developers
built with gcc 4.8.5 (GCC) 20150623 (Red Hat 4.8.5-36)
4、配置完环境变量后 查看版本
ffmpeg -version 查看版本
环境变量配置完成前 查看版本
cd /usr/local/ffmpeg/bin 到ffmpeg的安装路径下 ./ffmpeg -version 查看版本
备注：
如果出现一下错误：
[root@cf1f49f89164 ffmpeg-4.3.1]# ./configure --prefix=/usr/local/ffmpeg
nasm/yasm not found or too old. Use --disable-x86asm for a crippled build.
If you think configure made a mistake, make sure you are using the latest
version from Git. If the latest version fails, report the problem to the
ffmpeg-user@ffmpeg.org mailing list or IRC #ffmpeg on irc.freenode.net.
Include the log file "ffbuild/config.log" produced by configure as this will help
solve the problem.
则需要安装 yasm
wget http://www.tortall.net/projects/yasm/releases/yasm-1.3.0.tar.gz tar -zxvf yasm-1.3.0.tar.gz cd yasm-1.3.0 ./configure make && make install
