With Multichoice making a great deal of noise about its recent launch of a high-definition television (HDTV) channel and rumours abounding that by 2010 the country's national broadcaster will be capable of providing its viewers with HDTV coverage of the Soccer World Cup, more consumers are considering the purchase of a television that's capable of making use of the new, higher quality entertainment standard.

Darryl Squara, LG and Samsung product manager at Tarsus Technologies, believes that there is still some confusion in this market because of a complete change in terminology when high-definition televisions became available.

"Nobody has done a good job of educating the market about the changes," he says.

Instead of opting for the mainstay of quoting a horizontal and vertical pixel resolution as an indication of picture quality, Squara explains that manufacturers chose to quote the number of vertical pixels as a measure of 'definition'.

"Complicating matters even further," he adds, "they also decided to tack an 'i' or a 'p' onto the end of this new naming methodology, indicating whether the display delivers an interlaced or progressive (non-interlaced) scan picture, respectively."

"Combine these two new terms and it's not surprising that the market is confused," he chuckles.

While terms like 720p, 1080i and 1080p are confusing to the average television buyer, Squara says the new terminology can be easily explained.

Resolutions

Starting with resolution, he explains that the 720 part in a 720p set's specifications indicates that the vertical pixel count of the display is 720.

"So a television set with a resolution of 1280 pixels wide and 720 pixels high, has an HD resolution of 720 pixels," he says.

"The same rule applies to a display with a resolution that is 1920 pixels wide and 1080 pixels high. As the vertical resolution suggests, this display would have a HD resolution of 1080," he says.

For interlaced (i) and progressive (p) scan sets, there's a simple rule too.

"When interlacing sets refresh the picture displayed on-screen, they do so by refreshing all of the odd lines of pixels (lines 1, 3, 5, 7, 9 etc. all the way to 719) on one pass, and then all of the even lines of pixels (lines 2, 4, 6, 8, 10 etc. all the way to 720) on the following pass."

"It therefore takes two passes to refresh an entire picture," he says. "Progressive scan sets on the other hand refresh every single line of pixels with every pass and thus deliver a much faster picture — one that's more suited to sport and other fast-moving action," he says.

"Once one grasps this naming convention, it becomes relatively second nature to decipher that a 1080i television set is capable of displaying 1080 lines of pixels, but will only refresh every alternate line of pixels since it's interlaced," Squara says.

» What does HD-Ready mean? Find out on page 2!