CentOS 8

# 安装Linux存储库的额外软件包。
sudo yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
sudo yum install https://download1.rpmfusion.org/free/el/rpmfusion-free-release-8.noarch.rpm https://download1.rpmfusion.org/nonfree/el/rpmfusion-nonfree-release-8.noarch.rpm
sudo yum install http://rpmfind.net/linux/centos/8-stream/PowerTools/x86_64/os/Packages/SDL2-2.0.10-2.el8.x86_64.rpm

# 安装FFmpeg和FFmpeg开发包
sudo yum install ffmpeg ffmpeg-devel

CentOS 7

# 安装Nux Dextop仓库
sudo rpm --import http://li.nux.ro/download/nux/RPM-GPG-KEY-nux.ro
sudo rpm -Uvh http://li.nux.ro/download/nux/dextop/el7/x86_64/nux-dextop-release-0-5.el7.nux.noarch.rpm

# 安装FFmpeg和FFmpeg开发包
sudo yum install ffmpeg ffmpeg-devel -y

CentOS 6

# 安装Nux Dextop仓库
sudo rpm --import http://li.nux.ro/download/nux/RPM-GPG-KEY-nux.ro
sudo rpm -Uvh http://li.nux.ro/download/nux/dextop/el6/x86_64/nux-dextop-release-0-2.el6.nux.noarch.rpm
# 安装FFmpeg和FFmpeg开发包
sudo yum install ffmpeg ffmpeg-devel -y

测试&示例

# 测试是否安装成功
ffmpeg -version

# 例子：将MP3文件转成OGG音频文件

cd
wget https://archive.org/download/MLKDream/MLKDream_64kb.mp3
ffmpeg -i MLKDream_64kb.mp3 -c:a libvorbis -q:a 4 MLKDream_64kb.ogg

# 例子：将MP4文件转成OGG视频文件
cd
wget https://archive.org/30/items/I_Have_A_Dream_Speech_excerpt/I_Have_A_Dream_Speech_excerpt.mpeg4 -O MLKDream.mpeg4
ffmpeg -i MLKDream.mpeg4 -codec:v libtheora -qscale:v 3 -codec:a libvorbis -qscale:a 3 -f ogv MLKDream.ogv

翻译自：https://www.vultr.com/docs/how-to-install-ffmpeg-on-centos