Digital Television Head End Services
The head end services can be divided as follows:
- Contribution solutions
- Encoding and transcoding solutions
- DVB multiplexing and re-multiplexing
- Streaming solutions
- Other real time television signal processing
There are two kinds of contribution solutions – occasional and permanent. Occasional means receiving, decoding and descrambling media produced in the place of the event. The media is transferred via satellites or fibre networks. It is usually used to broadcast live in the TV-channels that we play out or on the online service portals that facilitate streaming. For example, fashion shows, concerts, sports events, etc.
Permanent TV-channel reception from different distribution platforms enables its re-transmission by local service providers (e.g. ZUUMtv). Permanent receiving is also used as an input to localise global TV-channels in Levira’s play-out centre.
In order to prevent exposure to weather and other significant risks, Levira has built back-up reception facilities for satellite connections in different areas of Estonia.
Encoding and transcoding solutions
Encoding is the compression of digital serial video and audio signals synchronously into a format and capacity which is suitable for using in DVB and IPTV networks that offer television service.
Most widely used video compression standards that we use are MPEG-2, MPEG-4 part10 or JPEG2000. When it comes to transcoding then the digital television programme decoding from its initial format and encoding to another format is usually done within one device or system. All processes are conducted in real time and the delay varies from a couple of frames to a couple of seconds.
In addition to real time video processing, we also transcode the professional Dolby-E audio format directly into Dolby Digital 5.1 audio format which is listenable for end-users.
DVB multiplexing and re-multiplexing
Multiplexing is a complex technical process applied live. Data streams and descriptive information, linked with the actual TV channel, are created as digital television service (DVB service). Digital television services, in turn, will be multiplexed into a multiprogramme transport stream when required.
Our multiplexers used to fulfil a wide variety of clients’ needs regarding subtitles in different languages, descriptors, dynamic aspect ratio, electronic program guide and conditional access.
Re-multiplexing is the re-grouping and filtering (with updated descriptive bit tables) of some of the parts of the existing digital television streaming content.
If necessary, we carry out scrambling of TV-channels. Conditional access management for consumers which is enabled by scrambling is usually done by our business clients.
We guarantee the correct temporal locking of DVB subtitles with the MPEG video component.’
Media is becoming more personal every day and people need more access to TV-channels and the content of media via public internet. This is why we are offering to our clients the technical aptitude to form suitable streaming versions over http protocol for a multiscreen environment over the public internet. The entire spectrum of different resolutions and quality levels enables to use wide-spread formats like HLS, rtmp, RTSP, MS Smooth Streaming, MPEG-dash, etc. The most common applications for streaming formats used by our clients are web television, mobile television and OTT.
Other real time processing of TV-signals
Since we have experience in digital television since 2003, we can offer many technical solutions – switching transport layers, high quality resolution transformation, changing interlaced display to progressive, changing colour information and transcoding of encoding profiles, improving picture quality and noise reduction, adding burn-in subtitles and other graphical elements (e.g. logos). In addition, adding masked auditorium recognition to media signals is becoming more widely used.