Residents of both the USA and the UK can expect to be dealing with the digital switchover within the next couple of years. What this means is that region by region, analog signals (also known as terrestrial TV) will stop being broadcast and viewers will need to buy an HDTV (High Definition Television) in order to watch the new digital signals being broadcast.
The differences between analog signals and digital signals are quite stark. On a basic level, analog television screens fire a picture onto the screen a whole frame at a time. Digital television, on the other hand, either fires all the odd lines at one time followed by all the even lines (interlaced scan mode at a screen resolution of 1920 x 1080 pixels), or one line at a time (progressive scan mode at a screen resolution of 1280 x 720 pixels). To an untrained eye digital interlaced and analog scan modes have little differences. However, progressive scan modes do improve the quality and smoothness of motion.
The most commonly used digital television standard in the UK is Freeview, which provides a number of free digital channels with a set top box, though most new televisions now have Freeview built in. The latest development is Freesat, which provides Freeview via a satellite dish and additionally will provide a number of HD channels.
One of the main advantages of Digital TV for viewers is that broadcasters are able to embed digital data into the streams, such as programme information and interactive channel menus (e.g. Press the red button now). This data is read and executed by a computer system in the television and made interactive via infra red on the viewer’s remote control pad.
Another huge advantage of digital television is that digital data takes up less bandwidth, meaning more channels can be broadcast at the same time. This gives viewers much more choice in what they watch and allows for follow up channels which broadcast the same programmes as their namesake, just an hour later. iptv subscription