Specifications

STEP 5: SMPTE Proposed Recommended Practice RP 175 (Digital
Interface for 4:4:4:4 Component Video Signals [Dual Link])
specifies de-multiplexing wide band digital 4:4:4 or 4:4:4:4
video signals into 4:2:2:0 and 0:2:2:4 pairs. This is for
interconnecting to other devices using standard 4:2:2
connections, either serial or parallel digital. The 8150 requires
that if the 4:4:4 signal is digital, it must be of the format
YCbCr; it accepts YCbCrK, but does not process the Key part
of the signal. (It cannot process digital GBR signals at the 4:4:4
sampling rate. However, if the Component Video + Key
Input module is installed, it accepts either wide band RGB
(GBR) or Y/R-Y/B-Y analog video.)
You can connect either part of the digital pair to any digital
input on the 8150. Be sure to note which input is the 4:2:2 (link
A, or luminance and co-sited color difference samples) part
and which is the 0:2:2 (link B, or non-co-sited color difference
samples) part. Since the 8150 does not process a key signal as
a part of the 4:4:4 signal, the terms "4:2:2" and "0:2:2" appear
below to indicate that key samples, if present, are not used.
STEP 6: You can select sources for the 4:4:4 Chroma Keyers in the
Keyer menu Sources submenu. When the Key Type is
Chroma 444, two pushknobs labeled Key 444 Cut Source #1
and Key 444 Cut Source #2 appear. Select the input you
connected the 4:2:2 (link A) part of the 4:4:4 signal to with the
Key 444 Cut Source #1 pushknob. Then select the input you
connected the 0:2:2 (link B) part to with the Key 444 Cut
Source #2 pushknob.
NOTE: Since the high resolution chrominance portion of
the 4:4:4 signal was sampled at twice the rate as a 4:2:2
signal, using only the 4:2:2 (link A) part of a 4:4:4 signal as
a source may result in aliasing of the half-sample-rate color
difference signals. The fill processor properly filters the
4:4:4 signal to 4:2:2 only when the Key Type is set to Chroma
444 and the Color Corrector Mode is set to RGB 444. Since
the Background A, Background B, Program, and Preset bus
Color Correctors cannot accept 4:4:4 signals, you should
use these signals only as chroma key fill sources in the
8150.
For more information on the 4:4:4 Chroma Keyers, see Section
4 – Keying in the 8150 Operations Manual.
8150 Technical Guide Option Installation
9100-0212-04 - May 2000
Option Installation
3-15