Play your video on TV, from Ubuntu without Miracast, Ezcast, AirPlay
Install :
UPnP-Inspector
is an UPnP Device and Service analyzer, and a debugging tool,
based on the Coherence DLNA/UPnP framework.
Rygel
is a home media solution (UPnP AV MediaServer)
that allows you to easily share audio, video and pictures to other devices.
Rygel-preferences
provides a graphical tool to configure Rygel and set custom preferences.
Transmart:
Plug in your device in TV (mine is Tronsmart T1000)
Configure it to your home wi-fi with your Android smart phone,
using Ezcast (Ezcast.apk from Google Play Store)
On Ubuntu PC
Connect your PC to Transmart wi-fi ("Transmart-9BABxxxx" mine)
Internet should work just the same.
(maybe not necessary?)
Start upnp-inspector (in "Programming", or /usr/bin/upnp-inspector)
Find your device and leave it open.
Start rygel-preferences (from terminal /usr/bin/rygel-preferences)
Select your media-folder, and save, close.
Start rygel (in terminal /usr/bin/rygel)
Go back to Inspector.
New sections should appear containing your media-folder.
Browse in it (double click) and find your movie, right click and execute.
Your movie should start playing on TV. :-)