An interactive solution for TV viewers
In this broadband age Internet Protocol Television or IPTV has become a reality on the internet. It is called IPTV because it uses internet infrastructure and special protocols to deliver contents to end-users.
Traditional TV systems depend on terrestrial broadcasting or satellite transmission to distribute programs to households. Cable TV multiplexes several channels into a single line and makes them available to subscribers through a network of optical fiber and coaxial cable.
IPTV outdistances traditional TV systems by its interactive features. Traditional TV systems telecast programs in a passive way, which means viewers have no room for interaction. IPTV, on the other hand, enables users to choose from programs and watch them to their convenience. Unlike existing television, IPTV viewers do not need to watch a program at a specific time. An on-screen TV guide allows them to search through contents. They can also adjust camera angle to enjoy panoramic view.
IPTV is an integral part of triple-play concept: video, voice and data. The spread of the internet has paved the way for enjoying all these services through a single network which is why the world's premier telecommunications service providers now consider IPTV as a lucrative way to generate profit from existing markets.
The idea of IPTV came in the limelight in 1994 when ABC television broadcast the 'World News Now' over the internet with the help of CU-SeeMe videoconferencing software. Since then significant development in IPTV has been achieved due to the widespread availability of broadband connection.
To enjoy IPTV, viewers need a PC or set-top box and internet access. At present many websites offer free access to IPTV channels and major television broadcasters worldwide are gradually transmitting their programs via the internet. Set-top box with broadband internet provides better performance to viewers than traditional cable television does.
IPTV allows viewers to watch both live programs (multicasting) and stored videos (video on demand). Video contents are compressed with either a MPEG-2 or a MPEG-4 codec and then send it an MPEG transport stream delivered via IP multicast in case of live program or via IP unicast for video on demand. Live program reception uses Internet Group Management Protocol (IGMP) version 2 whereas video on demand uses Real Time Streaming Protocol (RTSP).
IPTV has gained worldwide popularity which is increasing day by day. British telecommunications operator Kingston Communications has been successfully running its IPTV service, named KIT (Kingston Interactive Television), since September 1999. In addition, Kingston has also launched IP-based video-on-demand service and solution in 2001. It is one of the pioneer companies in the world to have unveiled IPTV and IP video on demand systems over Asymmetric Digital Subscriber Line (ADSL).
In the US, AT&T introduced U-Verse IPTV service in 2006. The company provides more than 300 channels in 11 cities and it is planning to extend its reach in the near future. In order to serve its subscribers efficiently, AT&T has dedicated a private network exclusively for video transport.
In Bangladesh broadband penetration is gradually increasing. Although IPTV is not apparently popular right this moment, fast-growing internet users and rising numbers of TV channels will soon provide this service for the people. It should be mentioned that several processes are underway to develop a complete IPTV solution. Recently Salauddin Salim, an IT & networking engineer at CSB News, has developed a system for live broadcasting of TV programs over the internet.
Salim started his work on IPTV when he was a university student. He has touted his system as being cost-effective and easy to operate. Resembling Satellite News Gathering (SNG), it is able to capture live video from any place within a short span of time. The wireless connectivity requires 256 kbps bandwidth and a laptop. More bandwidth considerably increases its performance. This IPTV solution is also compatible with guided media broadcasting, for which it needs 2 to 3 Mbps bandwidth.
The entire system is divided into four main components -- video source, transmitter, server unit and receiver. Video source part is considered as an input unit, which takes signal from various sources like satellite TV receiver, video camera, radio, video tape recorder (VTR) and CD/DVD. For real-time broadcasting, a satellite receiver is used to downlink the channel and input this signal to the video encoder.
Video encoder includes video capture card and encoder software to compress the video and then transform it into MPEG-2 format. Salim has developed some plugs-in in Visual Basic for the encoder software. Transmitter part is implemented in a separate PC and it is connected to the server. Signals from other sources also follow the same strategy before they are forwarded towards the server unit.
The server unit uses media server software to provide service to the end-users. To receive contents, users require a unique ID and password. Each user is assigned a special port. The server is capable of handling multiple transmitters, giving the viewers the opportunity to enjoy several TV/radio channels.
Server unit is directly connected to the internet through a high-speed line. A viewer sends their request by using a domain name or an IP address. Based on the request, the server sends the content. The viewer needs Windows Media Player (WMP) to watch it. If video is sent to the web server, viewers can see any TV program from the website. They can utilise WMP to enjoy radio programs also. Radio stations in this regard can live cast their programs from any place on the planet. By using this system, any TV channel can gather video contents from the internet and rebroadcast it to any specific location.
Salim told Startech that several companies, including a private TV channel, showed interest in his system. He said Tk 1,00,000 to 1,50,000 is needed to develop the entire system for commercial use. It is possible to downsize the cost for personal use. "In the near future, I will extend my effort to develop a autonomous TV station", he said.
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