OMV 7 - How install ffmpeg

[Chrisds]

Hi Everybody,
(I'm French. I hope my English is understandable)

I made myself a NAS with old equipment. I'm using openmediavault 7, portainer and ssh commands for the first time. I installed Minimserver not without difficulties but above all I cannot get minimstreamer to find ffmpeg.
I installed ffmpeg directly in the Container/ffmpeg/ folder. But in Portainer, I am unable to know the path to map the executable ffmpeg file with Minimserver. Unless I put it in the wrong place.
If you can enlighten me!
Thanks