Astra!

Tvheadend is a TV streaming server for Linux supporting DVB-S, DVB-S2, DVB-C, DVB-T, ATSC, IPTV, and Analog video (V4L) as input sources.

DVBlast is written to be the core of a custom IRD, CID, or ASI gateway, based on a PC with a Linux-supported card. It is very lightweight and stable, designed for 24/7 operation.

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.