jpvtx is a video text decoder. It accepts transport stream from stdin, and writes that to stdout, decoding teletext to /video/vtx/1/. It can be used with jpcam (and then gets the pids from that) or with pid[s] specified on the command line. I couldn't find the homepage, or no mention of it in the sourceforge. The tar can be found from ibiblio. I'd write the ebuild but I don't know how. :) http://www.ibiblio.net/pub/linux/apps/video/jpvtx-0.2.1.tgz
No progress here for 1 year; closing WONTFIX. Feel free to reopen with an ebuild.