Você pode usar a transmissão programada:
% bl0ck_qu0te%new my_media broadcast enabled
setup my_media input my_video.mpeg input my_other_movie.mpeg
setup my_media output #rtp{mux=ts,dst=239.255.1.1,port=5004,sdp=sap://,name="My Media"}
new my_sched schedule enabled
setup my_sched date 2012/12/12-12:12:12
setup my_sched append control my_media play