centos 7安装 ffmpeg 1.安装需要的源 ~~~ yum install -y epel-release wget http://li.nux.ro/download/nux/dextop/el7/x86_64/nux-dextop-release-0-5.el7.nux.noarch.rpm rpm -Uvh nux-dextop-release-0-5.el7.nux.noarch.rpm ~~~ 2.安装 ffmpeg ~~~ yum install ffmpeg ffmpeg-devel -y ~~~ 使用截图 ~~~ ffmpeg -i 1.mp4 -y -f image2 -t 0.001 -s 352x240 a.jpg ~~~ MP4转成FLV ~~~ ffmpeg -i 1.mp4 -c:v libx264 -ar 22050 -crf 28 1.flv ~~~ MKV 转 MP4 ~~~ ffmpeg  -i 1.mkv -y -vcodec copy -acodec copy 1.mp4 ~~~ 参数说明可参考[https://blog.csdn.net/machh/article/details/78647461](https://blog.csdn.net/machh/article/details/78647461)