Instruction manual

Guppy Technical ManualV7.4.0
86
Description of the data path
This is for the first line pair:
The first chroma signal R-Y is created by subtracting the averaged pixels:
Formula 2 is used for the first chroma (color difference) signal V.
For the second line pair, the Y signal is formed from these signals as follows:
This is balanced since it is formed in the same way as for the first line pair.
In a like manner, the second chroma (color difference) signal U is approximated
as follows:
In other words, the two chroma signals can be alternatingly retrieved from the
sequence of lines from R – Y and – (B – Y).
This is also true for the second field, which is generated by a vertical shift by one
line. Complementary filtering is thus a way to achieve higher sensitivity at a
slight expense of color resolution.
Formula 1: Y signal expressed via RGB and CyMgYeG
Formula 2: First chroma signal V
Formula 3: Y signal for second line pair
Formula 4: Second chroma signal U
Y
1
2
--
2B 3G 2R++
1
2
--
GCy+Mg Ye++==
RG+Ye=
RB+Mg=
GB+Cy=
with the assumption:
RY– 2R G–Mg Ye+GCy+–==
Y
1
2
--
GYe+Mg Cy++
1
2
--
2B 3G 2R++==
BY–– 2B G–– GYe+Mg Cy+–==