Interesting. There are a couple of options, some are "lighter" than others:
- Functional testing
- Validate something is playing: One approach you could take is to validate there's the status bar at the bottom of the screen, followed by typically a completely black screen and then a non-black screen. You can do that with visual image analysis tools.
- Validate there is a stream and it's the right one (the flow would be, switch a stream and validate the new one is now playing): This one is a little trickier. Typically the logo of the channel or some indicator would show on the screen that allows you to distinguish between one stream to another. Again here, you can do visual text or image analysis to validate.
- Video quality testing: there are a number of solutions in this field, one is Stormtest, providing a score and analysis for video streaming quality. Then, you should find a lab that allows you to connect the device(s) you want to test on (mobile devices, Set top boxes, OTT devices such as fire TV), to conduct E2E testing.
If you have any further questions or would like to follow up just ping me.
Hope this helps!