我如何计算 ffmpeg 编码此文件需要多长时间？
root@ubuntu-c-32-64gib-lon1-01:~# ls -l brs.mp4 --block-size=M
-rw-r--r-- 1 root root 626M Apr 27 08:24 brs.mp4
root@ubuntu-c-32-64gib-lon1-01:~#
root@ubuntu-c-32-64gib-lon1-01:~# ffmpeg -i 'brs.mp4' -acodec libmp3lame -vcodec libx264 theoutputfile.mp4
...
frame= 2069 fps=208 q=-1.0 Lsize= 15192kB time=00:01:09.43 bitrate=1792.5kbits/s speed=6.98x
video:14589kB audio:543kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.399940%
..