Grass Valley Kalypso Installation Planning Guide - Manual (Page 63)

Kalypso Installation Planning Guide 63
Optional Kalypso Classic System Components
Frame Restrictions
Although the Emergency Bypass frame is derived from Grass Valley
Group’s 8900 Series Modular frame, it has been designed specifically for
the Kalypso system, making the frame suitable only for Emergency Bypass
modules.
CAUTION Do not plan to install any other types of 8900 series modules in the Emer-
gency Bypass frame.
Power Supply Options
Redundant power options include:
• Redundant power supply for the Emergency Bypass frame, and
• Redundant power for the Local Aux panel: a 4-M/E Local Aux panel
can use up to two redundant power bricks while only one can be used
for a 2-M/E Local Aux subpanel.
See the Kalypso Emergency Bypass Option Installation Instructions and the
8900 Series Modular and SMS 7000 Router documentation sets for detailed
information. Online documentation is available on the Grass Valley Group
web site. The URL for the Grass Valley Group website is found on the copy-
right page at the front of this manual.
8950ADC Module - 4:4:4 Chroma Key Processing
The 8950ADC module in Grass Valley Group’s 8900 modular product line
can be configured to support full bandwidth chroma key processing on the
Kalypso Classic system.
Overview
In CCIR-601 digital signals, luminance (Y) is sampled at twice the rate of
the two chrominance signals (Cr, Cb) – hence the 4:2:2 designation to indi-
cate the sampling rate for Y:Cr:Cb respectively. So every pixel on the screen
has a unique luminance value, but color information is transmitted for
every other pixel. The receiving device typically repeats one chrominance
value for two pixels, or generates the missing values by some form of inter-
polation. In neither case is the information regained that was lost by the
original filtering to 4:2:2. This works for most video processing and trans-
mission applications since the human eye is not nearly as responsive to
color changes as it is to luminance changes. However, in chroma key pro-
cessing, the user is selecting a particular color out of a scene, so chromi-
nance bandwidth is paramount to achieving the best results.
In most cases, you can achieve excellent results even when using a 4:2:2
signal as both the video fill and the chroma key source. Pre-processing in
the chroma keyer uses interpolation as described above in order to have a