Tvheadend

I'm a long time MythTV user stuck there because I'm in the US and need to record HD from my cable box. The only option until now has been the Hauppauge HD-PVR which isn't supported by Tvheadend.

There are now a number of 'IPTV encoder' devices available that take in HDMI and output h.264 as an RTSP or an HTTP stream. They can be used in MythTV, but setup is fairly convoluted.

My question is, can I set up Tvheadend to display an EPG from xmltv, call a channel channel change script for my cable box, then view/record the IPTV stream?

Thanks.

Jerry