MICROTRONIX DX-2200, Руководство пользователя

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DX-2200
– SD/HD-SDI Text & Graphics Inserter – User Manual
Page 29 of 103
4.8.1.9.5 U
PDATE
G
RAPHIC
O
VERLAY
The GU command updates the video output of the Overlay by rendering all fields to the spare buffer and
exchanging the active and spare buffers.
After sending a sequence of commands that change the parameters of fields, send the GU command to
make the changes visible.
4.8.1.9.6 C
OORDINATE
S
YSTEM AND
F
IELD
P
OSITION
Each Graphic Field has two position coordinates referred to as Coordinate A and Coordinate B. One or both
of these coordinates may be used depending on the Graphic Field Type.
The coordinate system designates x=0000 and y=0000 as the top-left corner of the overlay for all video
formats. This is the default position for all fields.
The maximum value for the x and y coordinates is located at the bottom-right corner of the frame. For
1080p, 1080i, and 1080PsF formats the bottom-right corner is at coordinates x=1919, y=1079. For 720p
formats the bottom-right corner is located at x=1279, y=719. For NTSC format the coordinates are x=719,
y=485, and for PAL format x=719 and y=575.
NOTE: Some monitors will not display the entire video frame, particularly when operating in NTSC or PAL
modes. Graphic Fields placed close to the edges of the overlay may not be visible on some monitors.
NOTE: If the Overlay has been re-sized, the coordinate range may be smaller than the defaults for each
video mode listed above.
Any Field or portion of a Field that extends beyond the edges of the Overlay will not be visible.
The command set provides different options for setting the coordinates of a Graphic Field. The commands
GnnXxxxx, and GnnYyyyy set the x and y position for Coordinate A individually. The commands
GnnPAXxxxx and GnnPAYyyyy perform the same functions, but this form of the command can also set
Coordinate B, for example GnnPBXxxxx or GnnPBYyyyy.
If it also possible to set both x and y in a single command for Coordinate A or Coordinate B with the
commands GnnPAxxxx,yyyy and GnnPBxxxx,yyyy respectively. For all Graphic Field position commands,
the parameters xxxx and yyyy can be from 1 to 4 digits in length and may optionally be prefixed with zeros.
For example, sending G4X0200 and G4Y0400 sets the field position to (200, 400).
Changing the text position does not automatically update the video output.
Figure 11: Sample of active text and graphic logo