There are many alternatives to Tvheadend for Linux if you are looking for a replacement. The best Linux alternative is MythTV, which is both free and Open Source. If that doesn't suit you, our users have ranked seven alternatives to Tvheadend and four of them are available for Linux so hopefully you can find a suitable replacement. Other interesting Linux alternatives to Tvheadend are Astra (Paid), DVBStreamer (Free, Open Source) and DVBlast (Free, Open Source).
Astra is a professional software to organize Digital Broadcasting Service for TV operators and broadcasters, internet service providers, hotels, etc. Astra is an acronym for "Advanced Streaming Application".
DVBStreamer is an console based application to stream DVB/ATSC service(s) over UDP or to a file. It is more that just an app to stream AV though and feature a simple plugin architecture to allow more features to be added.