Lower video resolution to lower data costs

[RMPBS]

Hello, I have great video on my android phone however, it is burning up my cellular data plan. I want to turn down the video resolution and I can't seem to find an answer. Where is this determined?- by iptvprivate server, cell phone, apps on the phone ?? My player on the android phone is VLC.
Thank you for any suggestions,

[Dodgeit]

This would be determined by the server.