The Indian government made it compulsory to have a Set Top Box (STB) to watch cable television in some major Indian cities from April 1, 2013. This move is in lines with the government’s longterm objective of slowly rolling out Conditional Access Sytem (CAS) all over the country. With CAS in place, consumers will have to pay for all the channels they want to watch. Many analysts are expecting that the roll-out of CAS may make many consumers to switch to Direct-To-Home (DTH) services as they provide better viewing experience in the form of picture quality and freedom from any interruptions to the service due to disconnected cables . DTH services all over the world are offered using two compression technologies, viz. MPEG-2 and MPEG-4.
The first two DTH operators in India Dish TV and Tata Sky used MPEG-2 standard while the operators who entered the market later like Airtel, Reliance, Sun, and Videocon used MPEG-4 standard. The operators who offer their service using MPEG-4 now claim that their standard is superior to MPEG-2 and its provides better video and audio quality. But, is MPEG-4 really superior to MPEG-2 ?
MPEG-2 and MPEG- 4 are just two different compression standards developed at different points of time. Videos compressed using MPEG-4 at a bit rate are of better quality than those compressed with MPEG-2. But if videos are compressed in a lesser bit rate in MPEG-4 than in MPEG-2 there will not be any significant difference in quality. DTH signals are transmitted through a satellite to you STB. DTH operators take transponders for rent on a satellite to broadcast their signals. Each of the transponder on a satellite has a fixed bandwidth and the number of channels that any transponder will be able to handle depends on the bit rate of channels that are transmitted. For E.g. if the bandwidth of a transponder is 50 Mbps, DTH operators can broadcast upto 25 channels with each of the channel encoded at 2 Mbps. DTH operators using MPEG-4 can use the transponder’s capacity more effectively as their compression technology is superior to MPEG-2. In other words, they can broadcast more channels using the same transponder than the DTH operators using MPEG-2. In the above given example, DTH operators using MPEG-4 can reduce their channel’s bit rate to 1.2 Mbps and broadcast nearly 40 channels. But as explained above, a video compressed at a bitrate of 1.2 Mbps using MPEG-4 is not superior to the one compressed at the rate of 2 Mbps using MPEG-2. So a DTH operator using MPEG- 4 can either follow the same bit rate as MPEG-2 operators and offer superior quality or reduce the bitrate and broadcast more number of channels at the same quality.
So, the first thing you need to make sure before making a choice is to verify whether a DTH operator using MPEG-4 is passing the qualitative benefits of a superior compression technology to you or not. If they are indeed passing the qualitative benefits to consumers then you can select that operator. Otherwise, there is no difference between and a DTH operators using MPEG-2 and MPEG-4.
As the popularity of HD channels spreads in India, all DTH operators may be compelled to switch to MPEG-4 as they need to use their transponders more efficiently. Also do remember to consider the other aspects of a DTH service provider like pricing, packages, service quality, etc. before making a choice.