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technology<br />
WE DON’T NEED THIS DEBATE.<br />
MOVIES, NEWS, KIDS, AND SPORT<br />
ALL WORK IN INTERLACED FORM<br />
JOHN IVE, SONY<br />
below. The different sizes of TV: PAL and<br />
NTSC is standard definition UK and US<br />
television; 720HD and 1080HD is high<br />
definition; 2K is film.<br />
76 d<br />
720<br />
625 SD (PAL)<br />
525 SD (NTSC)<br />
6<br />
2<br />
5<br />
5<br />
2<br />
5<br />
Clear as mud<br />
Three image formats currently<br />
dominate HDTV production: 1,920-x-<br />
1,080 in 50 or 60i varieties; 1,920-x-<br />
1,080 in 24, 25, or 30p; and 1,280-x-<br />
720 in 60p. Or, to use their shorthand,<br />
1080i, 1080p and 720p.<br />
The first two numbers refer to<br />
the resolution. So 1080i is 1,920 pixels<br />
wide by 1,080 lines deep. The second<br />
set of numbers is the number of fields<br />
per second that are displayed on the<br />
screen. Because electricity in the<br />
States runs at 60Hz frequency, HDTV<br />
in the US displays at either 60 or 30<br />
fields a second, in Europe (50Hz) it’s<br />
1280<br />
720 HD 7<br />
2<br />
0<br />
This image of Trafalgar Square was shot in 1080i by AHC Post. Although a near<br />
perfect image, zooming in on the verticals clearly shows the interlacing and<br />
“inter-line twitter” that fans of progressive displays – including the European<br />
Broadcasting Union – say is one reason for choosing progressive.<br />
2<strong>04</strong>8<br />
2K Film 1 5<br />
3<br />
6<br />
1920<br />
1080 HD 1<br />
0<br />
8<br />
0<br />
50 or 25 fields a second. 24 is based<br />
on film.<br />
The letter at the end is either “i”<br />
for interlaced, or “p” for progressive.<br />
Both are different ways of getting<br />
a picture onto a screen. Interlacing<br />
is where the display writes alternate<br />
lines – lines one, three, five, and so<br />
on, then lines two, four, six and so<br />
on – to build up the whole picture<br />
on screen. Half the picture is drawn<br />
with every refresh, resulting in a<br />
<strong>com</strong>plete frame being drawn 25<br />
times per second. The technology<br />
was developed because early TV<br />
tubes couldn’t draw the whole picture<br />
before the top began to fade. This is<br />
how standard definition works. It’s<br />
also why TVs “flicker”.<br />
Progressive is where the entire<br />
image is written in line order and<br />
then displayed on the screen, so<br />
lines one, two, three, four, up to<br />
1,080 are written and then the image<br />
is displayed. This gives a smoother<br />
image without flicker, and it looks<br />
like film. This is how your <strong>com</strong>puter<br />
monitor displays.<br />
Sony kicks off<br />
So far so clear. The confusion – and<br />
wading through the Web sites, news<br />
groups and industry press releases,<br />
it is clear that the HDTV-world is very<br />
confused – <strong>com</strong>es when you start to<br />
look at how these three different<br />
standards are being applied.<br />
1080i has been adopted as the<br />
<strong>com</strong>mon image format by the States,<br />
and to a large degree by Australia,<br />
North America, and Asia. The big<br />
technology developers and<br />
manufacturers like Sony have also<br />
been happy to adopt this standard.<br />
But, just to make things more<br />
<strong>com</strong>plicated, Europe has not.<br />
Instead, at a European<br />
Broadcasting Union (EBU)<br />
conference towards the end of<br />
last year they came down firmly<br />
in favour of 720p. This nearly gave<br />
Sony Europe’s director of strategic<br />
planning, John Ive, a heart attack:<br />
“We don’t need this debate,” he said.<br />
“Movies, entertainment, kids, current<br />
affairs, docs, and even sport work<br />
wonderfully well in interlaced form.”<br />
He would say that of course – his<br />
<strong>com</strong>pany is the biggest supplier<br />
of 1080i production and broadcast<br />
gear in the world.<br />
In turn, that made Phil Laven,<br />
director of EBU’s technical<br />
department, <strong>com</strong>mit a sharp U-turn.<br />
The final decision was turned into<br />
a “work in progress” and the issue<br />
was left fudged, again.<br />
Excuse me?<br />
“Why is Europe promoting 720<br />
progressive while the rest of the<br />
world is getting on with 1080<br />
interlaced?” you might ask. Well,<br />
to clarify their position after their<br />
bun-fight with Sony, EBU released<br />
a statement in January this year. It<br />
said that most consumers in Europe<br />
are moving towards widescreen,<br />
non-CRT, flat panel TVs. All these flat<br />
panel displays and HDTV projectors<br />
will be progressively scanned.<br />
Because the displays are<br />
progressively scanned, said EBU,<br />
broadcasters should broadcast in<br />
progressive. This is because when<br />
you convert from interlaced to<br />
progressive you lose quality. This is<br />
done in the consumer’s equipment<br />
and it is the quality of these filters<br />
which determine the quality of the<br />
image: much better to broadcast<br />
in progressive and display in<br />
progressive.<br />
Another good reason –<br />
and perhaps the main one – for<br />
re<strong>com</strong>mending 720p over 1080i is<br />
bandwidth. With current <strong>com</strong>pression<br />
technologies it is less bandwidthheavy<br />
to broadcast 720p.<br />
So, despite Sony’s heart attack,
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