Changing VLC player size, channel, volume from host server

[vlcfirsttime]

Hello,

I must apologize first, that I am a complete beginner at programming and also my capability of English is poor, so I might asking this question on a wrong place or maybe nonsense idea.
This is our new project as follows:
One of my client asked me to build a system to show a TV broadcast or a original tourism video on several TV displays which are settle in a Hotel, Shopping center, or other places.
Each display will be connected to a PC by HDMI, and also connected to the LAN.
The host server computer needs to control the VLC player's(or the software which embeds the VLC) size, location on the screen, channel, volume which are installed to the client PC.
We need to change the size and the location of the VLC player because we are going to show other information on the screen such as web page or image data on both side or under the player.
We have succeed to play the TV broadcast by using USB type TV tuner on each client PC and play the movie file an local hard disk.
Although, I do not know how that I can remote control the channel and the size of the player from the host server.
We have employed one programmer to solve this problem, and he suggested to use some kind of API to control the VLC player, but it seems that his computer environment(Linux, debian?) will not succeed to control after compiling the program using the API.
He says that this API might work by using different operating system such as Ubuntu, but we are not sure that the operating system is the problem or not.
Maybe we should use Windows OS instead, but we want to use Linux OS for the client PC.
This is our problem now, and we do not know how to use the API control for VLC.
Also, maybe the API can not control all of our requests, therefore in this case, I would like to know what is capable and what is not.

[Jean-Baptiste Kempf]

http://www.linutop.com/index.en.html look at digital signage there.

[vlcfirsttime]

Dear Mr Jean-Baptiste Kempf,

Thank you for your reply.
I will tell my programmer to check the linutop OS as soon as possible.
I have one more question, about VLC command-line options
My programmer requests that he needs to know how to use the VLC command-line options.
He is trying to launch the VLC player by using command-line options, to command the width, height and the coordinate on the screen.
He thinks that the correct command line is as follows:
vlc --width 640 --height 480 --video-x 0 --video-y 0
Although, this was not the correct command line which can launch the VLC player, but not to change the VLC player size and the location on the screen.
We are using debian 9 forthe operation sysytem.