I'm not sure what you mean. What video are you referring to?

Some stations have gates and the QR code in the app can be used to open some of these gates.

In some stations your reservation will also operate the gate - Eurostar and French TGVs come to mind.

Thanks dear yorkie, so QR code in our phone can open the gate to enter to train platforms.kindly refer below video, she is tapping her ticket to open the gate, in our case, we will have QR code. Correct me if am wrong. 

Yes in the netherlands the gates have also a QR-Code scan to read Eurail Passes or international tickets.

Thanks a lot

You are welcome.
 

Just one more thing, in the UK some, but far from all, stations have these gates, but they don’t read QR codes. There should always be somebody on duty to open the gate manually or a help button for remote release.

On the train the inspector will also be unable to read your QR code but, as long as you have added the train to your pass, all the required information is shown in the text as well, but you may need to scroll down a bit.