2. Advantages of DVCPRO HD
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2-3 DVCPRO HD's 4:2:2 Sampling Rate Is
Most Beneficial for Professional Video
Production
DVCPRO HD and DVCPRO 50 convert video signals to digital component signals
at a 4:2:2 sampling (digitizing) ratio before recording. The resulting 4:2:2 digital
component signal complies with the SMPTE259 Standard SDI signal specified in
ITU-R601.
DVCPRO HD format samples the brightness signal (Y) at 74.25 MHz and the
chroma signal (Pb/Pr) at 37.125 MHz, and combines each set of four Y samples
with two Pb and two Pr samples. With the large amount of information it provides
for the color difference signal, this system helps maintain outstanding color
resolution.
As you know, 4:2:2 sampling is one of the conditions required for source footage
and interfaces used in high-end production processes such as post-production.
This is because 4:2:2 sampling maintains rich colors that otherwise would be
degraded in editing.
Another reason is related to chroma-key composition. Because 4:2:2 sampling
• DVCPRO HD
• DVCPRO 50
4:2:2
Line 1
Line 2
Line 3
Line 4
Y
only
Y
only
Y
C
R
C
B
Y
C
R
C
B
