With the DAARSAT rollout, a lot of noise is being made about High Definition (HD). Are Nigerians ready to embrace this technology? What is high definition? How does it compare with Standard Definition? And is DAARSAT correct to deploy a new but more expensive technology when all its competitors are using the old but cheap Standard Definition technology?

high definition is about five times clearer than SD and is soon to become the standard in visual entertainment. anybody who has a Plasma/LCD/OLED/RPTV display capable of at least 720p (1280 pixels horizontal X 720 pixels vertical scanlines, P stands for PROGRESSIVE scan, usually the vertical lines are taken to denote the kind of resolution capabilityy) is High-Def ready in the barest minimum

however it doesnt end there; there is also 1080i (1920 X 1080, I means INTERLACED, more on Progressive and Interlaced later) and 1080p resolutions with 1080p being the highend resolution on any 16:9 widescreen. but to benefit from these capabilities one needs a medium that outputs the signal, so hooking up a HDTV to your standard DVD or DVB box/satellite decoder will not give you HD quality picture (though you will benefit from full contrast and deep colors, and there are certain DVD Upscalers that raise the Standard REsolution to 720p).

picture it this way: NTA and AIT broadcast in 480i (ie 640 X 480 interlaced also known as VGA) on 4:3 aspect ratio. this means they broadcast in Standard Definition, so your HighdEfinition TV will receive this signal as SD and output it onscreen as SD.

this means that to benefit from HD you need a HD medium such as a Bluray player, HD-DVD, HD-DVB/STB and of course DVD Upscalers. but here too is another caveat: if you have a keen eye you wont get the full HD experience using just composite or RCA connectors; you need at least a DVI cable, or better a HDMI cable and best of all a DisplayPort digital connector to get the full nine yards of high def. (if you've ever seen a HD movie or played a ps3 or xbox360 on full HD you'll know what i mean)

there are lots of flatpanel screens sold that arent really HD, but standard definition widescreen displays and some that are high def but don't support HDMI and/or displayport connectors and yet others that don't offer TrueHD (ie 1080p).

now back to your question: anyone that has a display that supports HD is HD-ready, and there are lots of people having such displays (though it must be said most are unaware of the benefits; simply hooking the TV to a standard DVD or satellite Set top box is okay for them). if DAARSAT offers HD STBs then indeed we are ready for HD, and i commend them for going with HD because thats where the trend is going and because of their pioneering work more naijans are being drawn towards the HD movement.



now back to Progressive Scan and Interlaced.

Interlace was a technology used in raster displays (eg CRT monitors and your standard def TVs) to improve picture quality by scanning every second line of pixels diagonally from the top left to the bottom right corner of the display. before the first line fades from vision the second is scanned and so on, giving the impression of constant motion. this works best in CRTs, as i mentioned earlier (the flickering you see in a monitor within a monitor or tv within a tv), but terribly in LCD displays and Digital Light Processing (DLP) panels because they don't use raster to paint pictures onscreen (and thus no white noise).  however the flickering effects of interlaced can be minimized with a technique called Interpolating.

therefore, because most LCD/DLP screens come either 720p or 1080p, 1080i now really means a sort of HD broadcast rather than display capability.

Progressive Scan means drawing all the display lines sequentially rather than the odd-first even-next approach of Interlaced scanning. because the vertical lines of resolution are most important, Progressive gives a better picture quality with no flickers and aliasing and artifacts. however this uses a greater bandwidth than interlaced broadcast and hence is expensive.


so there you have it; 1080p (1920 by 1080 p) is true HD (most computer monitors these days are 1024 X 780, better known as XGA), HDMI and DisplayPort give better picture output, DARRSAT has done a great job, some naijans are HD Ready.

hope this helps.

cheers and laters.