Hello all,
Back to your problem, i think most cable tv operators do this (using proprietary software and/or hardware equipment), so perhaps consulting a few of them would be a good idea to get started.
Last year we had a session on pure data in sarai, and he was using webcam streaming with tickers. One can use pure-data on all platforms check their website at http://puredata.info/ Though I am not sure how will that fit with Tata-sky.