Product guide

The iScan Ultra performs excellent 3:2
pulldown detection. In addition, it also
recognizes the 2:2 pulldown sequence
used for converting PAL film and comput-
er graphics to video. For these film and
computer graphics sources, the iScan
Ultra will reassemble the original progres-
sive frames with no unnecessary filtering
of image detail.
Time Base Corrector
The iScan Ultra features a full-frame Time
Base Corrector, or TBC, which makes a
significant improvement in the overall
image quality. The TBC removes timing
variations and irregularities from the
input video image before sending the
image to the iScan’s progressive output.
These irregularities are particularly
noticeable on video sources with poor
timing stability such as VCRs, where they
can be seen as jittery or wavy edges on
objects, bends in the sides of the image,
or an instability or shimmering of the
image as a whole. The image may also
appear to be less crisp or sharp overall
due to these timing problems.
(Conversely, DVD players have very good
timing stability and do not show these
symptoms.) This is particularly true when
a VCR is playing in fast forward or
reverse, or is in pause mode. These timing
irregularities can cause problems with
some displays, from periodic blanking of
the picture to no picture at all. The TBC
corrects these errors and allows an
unstable video source such as a VCR to
produce a stable image on most displays.
The iScan Ultra’s TBC is always turned on,
so that it can improve the quality of all
video sources used with the iScan Ultra
(except for the ‘Pass-Thru’ input).
Digital DVI Output
The iScan Ultra features a digital DVI
output. The DVI interface, based on
Silicon Image’s TMDS™ technology, is a
new standard digital interface between a
PC and a digital display. DVI is quickly
becoming an available digital interface for
consumer electronics devices such as
set-top boxes and DTVs. The DVI interface
enables a digital link between the iScan
Ultra and a DVI-equipped display, for the
highest video quality without the losses
associated with analog interfaces.
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How It Works (continued)