Progressive And Interlaced Video - Crestron UPX-2 Operation Manual

Crestron UPX-2 Universal Presentation Processor
conventional analog NTSC picture resolution, with less noise. SDTV is similar to
DVD or satellite TV quality but not considered high-definition television (HDTV).
SDTV can provide both widescreen (16:9) and traditional (4:3) aspect ratio formats.
Most devices only output 4:3 and support the other aspect ration in a letterbox
format. Refer to "Aspect Ratios" on page 74 for more information.
480i (Composite Video)
A form of standard-definition digital television (4:3 aspect ratio, 720 x 480
resolution) that approximates the quality of analog television but is not considered
high-definition television (HDTV). The i stands for interlaced scanning. Even
though the native resolution of DVDs is 480p, they are viewed at 480i on an NTSC
or PAL analog television.
480p
A form of standard-definition digital television comparable to VGA computer
displays but not considered high-definition television (HDTV), though 480p is
discernibly cleaner and slightly sharper than analog television. 480p has a resolution
of 720 x 480 and is a 4:3 aspect ratio. The signal is supplied in Component format; Y
(luminance) and separate chrominance signals P , and P . The native resolution of
b r
DVD is 480i, but that resolution can be seen only if a DVD player outputs a
progressive scan signal that is converted by an internal line-doubler and the DTV has
progressive-scan or component-video outputs; it is also known as EDTV (Enhanced
Definition Television). It is recommend that you use the 480i signal from the DVD
(or other device) that has 480p and allow the UPX-2 to line-double the signal. The
UPX-2 has a better line-doubler than most others.

Progressive and Interlaced Video

Interlaced scanning is the standard for analog televisions. An interlaced scan draws
the lines of each picture frame in two separate passes. Half of the 525 scan lines are
drawn in the first pass (the even lines), and the other half (the odd lines) are drawn in
the second pass. A complete picture of odd and even fields is painted on the screen
30 times a second.
This technique was developed to compensate for the limited transmission
technologies available when television was new, and was satisfactory in its day.
However, improvements in display technology revealed some serious shortcomings
of interlaced signals. Image flicker is more noticeable on larger screens, and on the
edges of sharp objects. Vertically adjacent horizontal lines are not from the same
field (a 60th of a second apart) so motion displacement becomes noticeable,
especially on high-resolution displays.
Progressive scanning draws all 525 lines of a picture frame in a single top to bottom
th
scan in 1/60 of a second.
72 ¥ Universal Presentation Processor: UPX-2
Operations Guide – DOC. 6276C