Progressive Scan (The best )
- Labelled as: Probably Progressive Video/YUV,
- Output progressive scan YUV
component video in the form of 3 BNC or RCA connectors.
- Connect to the 3 video inputs of a progressive-scan
line multiplier or a progressive-scan TV. Toshiba's version
is called ColorStream PRO.
- This format preserves the progressive
nature of most 24-frame movie discs, providing a film-like,
flicker-free image with higher vertical resolution and smoother
There's a new term in video now being bantered
around in home-theater circles: progressive scan.
What is it? How does it work? What makes it so special?
These are all good questions, especially considering that
progressive-scan players are now drastically dropping
|Interlaced video draws
in a picture.
||Progressive scan cleans
To illustrate the meaning of progressive scan,
let's take a look at that old analog TV in your living
room. It most likely uses the interlace method
to draw onscreen images. That is, the electron gun at
the back of the TV tube first fires off the odd lines
of the onscreen image, then during a second pass, it shoots
out the even-numbered lines. This all occurs within 1/30
of a second, but what you wind up seeing is an acceptable
picture that has some occasional flicker or artifacts.
To improve upon those images, sophisticated
front- and rear-projection TVs have used and continue
to use line doublers. Line doublers turn an interlaced
NTSC picture into a progressively scanned image for big-screen
home-theater use by effectively doubling the number of
lines on the screen, making the scan lines that make up
the picture less visible.
Newer digital HDTVs draw progressive-scan pictures.
Progressive scan works in the same manner as your computer
monitor. It writes one full frame of video from left to
right across the screen every 1/60 of a second. And since
you get an entire image drawn at one time--as opposed
to an image split into two--a progressively scanned video
image is better than an interlaced one. This also means
you wind up with few artifacts from the interlacing process
or motion artifacts introduced into the picture.
Progressive-scan DVD players will work only
with digital HDTVs and are not compatible with older analog
sets, due to their higher horizontal-scanning frequency
of 31.5kHz. One big feature that will be in any progressive-scan
DVD player worth its salt is 3:2 pull-down circuitry.
This tiny bit of silicon makes all the difference with
your movies, by helping differentiate between the 24fps
(frames per second) frame rate of film and the 30fps frame
rate of video. In plain English, it smoothes out the picture
and virtually eliminates what we in the industry call
The best example of jaggies that comes to mind
is in the very beginning of the Star Trek: Insurrection
DVD. The movie opens with some children playing in haystacks.
Then the camera pans to a village with a number of bridges
and rooftops. If you watch this scene on an HDTV with
a line doubler that lacks 2:3 pull-down (and almost all
of them do) and a regular interlaced DVD player, you will
see these nasty jaggy artifacts crawling along the bridge
railings and all around the edges of the rooftops. Of
course, now that you know what to look for, you'll be
haunted by them in every film-based DVD you watch from
now on. (Sorry.)
The other big reason why progressive-scan DVD
players deliver much better pictures is because they can
read extra data tags on DVDs and the players can work
their image-processing magic in the digital realm before
they output the video signal in analog form. (At this
time, all home-theater DVD players output an analog signal.)
If you feed an interlaced DVD signal to a digital HDTV,
the TV's line doubler must convert the signal to digital
before processing the image, and the TV doesn't have access
to the extra data stored on the DVD. For this reason,
a progressive-scan DVD player can deliver a sharper, cleaner