It is little bit confused, there is actually functionality on the almost every tab to set up view to Expert but i could not to find right one to get CAs tab.
is it a bit confusing, go to settings -> general -> there is a viewlevel for the whole tvheadend -> the ca tab only pops up if expert is used (I open a ticket at Tvh - current situation isn't that nice)
but i am not sure if there is implemented transcoding
There is no transcoding for RPi, all ARM powered devices didn't have enough cpu power to do this.