DigitalVideoAndHDTVAlgorithmsAndInterfaces.pdf

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Figure 41.2 480i component
digital 4:2:2 luma waveform
SMPTE 253M, Three-Channel RGB
Analog Video Interface.
708 CLEAN
2 359 360 716
736 0
720 SAL 719
0H Sample clocks, 13.5 MHz
858 STL line sync datum (0 H ): If digitized, that sample would
take the 50% value of analog sync.
Figure 41.2 above shows a waveform drawing of luma
in a 480i component digital 4:2:2 system.
Component analog R’G’B’ interface
A component 480i R’G’B’ interface is based on
nonlinear R’, G’, and B’ signals, conveyed according to
Analog electrical interface and Analog mechanical interface,
on page 408.
In studio systems, analog component R’G’B’ signals
usually have zero setup, so zero in Equation 41.1 corresponds
to 0 V DC . According to SMPTE 253M, unity
corresponds to 700 mV. Sync is added to the green
component according to Equation 41.3, where sync and
active are taken to be unity when asserted and zero
otherwise:
7
3
G'sync = ( active ⋅G')
+ −sync
10
10
( )
Eq 41.3
Sadly, the SMPTE R’G’B’ analog interface is unpopular,
and “NTSC-related” levels are usually used, either with
or without setup.
CHAPTER 41 480 i COMPONENT VIDEO 507