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Summary
Transmission of the digital television via IP network is the next step in the development
of the broadcasting platforms. This full service digital solution gradually replaces the terrestrial,
satellite and cable television. The IPTV service shares many properties with the OTT (Over The Top)
service, e.g. YouTube, Netflix however, it does not guarantee the quality of service using the Internet
instead of a dedicated network.
The aim of this engineering thesis is to design and implement a headend
and an IP infrastructure which would allow for a transmission of a television signal. The headend has
been receiving television channels from three free-to-air multiplexes broadcast
by the digital terrestrial television DVB-T MT4171 Media-Tech receivers. According to the subject’s
assumptions the retransmission was carried out by multicasts with MuMuDVB software. The network
was built with Allied Telesis switches, which were available in the institute and which operated
the IGMP protocol. A user could watch digital television via Stalker middleware and the MAG 250
decoder.
The paper includes a review of methods employed in audio and video data compression.
The conditional access system which provides the access to the contents broadcast only
by the authorized users was described. The analysis of available sources of signals transmitted to the
headend was performed along with the description of the DVB-T, DVB-S and an IP exchange point.
Methods concerning audiovisual data transmission in IP networks were discussed and multicast
protocols, IGMP, UDP and RTP were described. The commercial solutions for the headend, which
require 15 000 PLN in order to operate three digital terrestrial multiplexes, were presented. In the
project the open-source software was used in order to minimize expenses to the purchase of three
DVB-T tuners, which are available on the market for approximately 150 PLN. A list of decoders
employed in the IPTV networks was created showing their direction of development. The latest
implementations are based on the Android system and comprise the multimedia centre with thousands
of applications and games. The MAG 250 decoder is built on the Linux while the Stalker middleware
is viewed in the browser integrated with hardware by the procedures called with the JavaScript.
In the last chapters of the paper there are assumptions and requirements for the project and
its implementation. There is a step-by-step description of the construction of IP based network,
implementation of the headend and the process of Stalker’s installation and configuration. In the last
part of the paper author summarizes whole thesis and describes plans for further development of the
project.