GRASS VALLEY 1200, Installation And Service

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3-17
Frame Modules
Crosspoint Matrix
The Crosspoint Matrix (Figure 3-6) consists of 16 inputs by 16 outputs by
10 bits repeated twice, once for luminance and once for chrominance. Not
all of the available outputs are used.
The crosspoint matrix is designed so that any of the inputs can be
connected to any of the outputs without limits. To accomplish this, all 16
zero bits (from the 16 inputs) go into one crosspoint, all of the one bits go
into the next crosspoint, and so on for all of the crosspoints. Then if input
one is mapped to output seven in the mapping menu, each of the 20
crosspoints connects input one to output seven. This connects each of the
10 luminance bits and each of the 10 chrominance bits from pin 1 input to
pin seven output. The outputs of the crosspoints are then reorganized into
video buses.
The Output buses for the Y (luminance) crosspoints are the following:
■
Luminance for Background A and B (2 buses)
■
Key and Luminance for Key 1, Key 2, and DSK (6 buses)
■
Luminance for Aux 1 and Aux 2 (2 buses)
■
Luminance for Chroma Key (1 bus)
The Output buses for the C (chrominance) crosspoints are the following:
■
Chrominance for Background A and B (2 buses)
■
Chrominance for Key 1, Key 2, and DSK (3 buses)
■
Mask/Depth for Key 1 and Depth for Key 2 (2 buses)
■
Chrominance for Aux 1 and Aux 2 (2 buses)
■
Chrominance for Chroma Key (1 bus)
One crosspoint in the matrix takes the output of the Chroma Keyer
Submodule and can place it on any or all of the three key buses.
The crosspoints can create a matte for each output. They do this by simply
generating the bits required to create a given color.
The Crosspoint Module includes delays on all of the buses so all signals can
be timed to arrive at their destination simultaneously. This compensates
for the various delays through the system.