The set-top box provided by Alticast connects to a DVB-T terrestrial antenna and a DSL line and runs Alticast’s GEM+Java Middleware (Alticast OTTV Service Solution). It combines terrestrial broadcast reception (DVB-T) with VoD streaming from the servers of the Italian Broadcaster Mediaset over the internet. The hybrid platform implements both the recent Over-The-Top (OTT) profile and the broadcast profile of the GEM 1.3 specification. These boxes are already deployed in the DGTVi broadcast network in Italy, where they complement the linear broadcast TV offering of the broadcaster with the VoD portal that offers the latest movies and TV series. Content is streamed over the internet in high definition, which is made possible through the adaptive streaming capabilities of the GEM OTT profile.
Why Adaptive Streaming?
The internet is not able to guarantee a constant bandwidth to video streaming.
Bandwidth variations are common on the internet and specific measures are necessary to ensure uninterrupted viewing, which the consumer expects from a premium service. Today’s non-adaptive streaming solutions do not support HD streaming, as the required constant bandwidth is not available on a typical internet connection. Adaptive streaming was designed to handle bandwidth variations. During playback the STB continuously measures the available stream bandwidth and switches to a different stream with a lower bandwidth requirement (bitrate) in instances where the available bandwidth is not sufficient for uninterrupted streaming. When sufficient bandwidth becomes available again the box dynamically switches back to the stream with the higher bitrate.
The IBC demo scenario
The demo showed a commercial hybrid service using the most recent GEM 1.3 standard. It combines the reception of a local DVB-T stream with live OTT streaming over the internet from Mediaset’s VoD servers in Italy. While watching a broadcast program, the viewer can press a VoD button (similar to the ‘Red button’ in other environments). This launches the VoD portal application, which shows different available categories (movies, TV shows, sports, 7 day catch-up, etc.).