Studio Technologies 5152 V.1 - Manual (Page 27)

Model 5152 User Guide Issue 5, September 2013
Studio Technologies, Inc. Page 27
Model 5152
Video Generator/Audio Embedder Module
created by the embedding process will
only be present for the specific configured
audio group or groups. For example, if the
Model 5152 has been configured for digital
audio inputs 1 and 2 to be embedded into
SDI group 3, then there will be no ancil-
lary data packets present in the SDI output
for groups 1, 2, and 4. Only if a connected
SDI signal has embedded audio on those
groups (1, 2, and 4) will they be present in
the Model 5152’s SDI output(s). This can
be significant as it’s been discovered that
some equipment that receives SDI signals
expects that embedded audio will be pres-
ent, at a minimum, on group 1. So embed-
ding audio, as an example, that is only
present on group 3 could cause an issue.
GPI and GPO
Model 5152 modules with serial numbers
of 00251 and later include a GPI (general-
purpose input) and a GPO (general-pur-
pose output) function. Depending on the
application, connections may have been
made to the GPI and/or the GPO.
GPI
The GPI function allows the Model 5152’s
audio embedder function to be disabled
(turned off) in response to an external
command. This requires that the GPI has
been connected to an external switch or
contact closure and the function configured
to be enabled. When the GPI is open (not
shorted; logic “high”) the specific action of
the embedder function would be controlled
by the embedding configuration param-
eter. When the GPI is shorted to common
(pulled “low”) the embedding configuration
is temporarily ignored and the embedder
function is disabled. Any embedded audio
present on the SDI input source will pass
through to the Model 5152’s SDI output(s).
GPO
The GPO may be connected to an LED
indicator or computer-based monitoring
system. A configuration choice allows the
GPO to be configured from among five
choices. One is disabled and the GPO will
remain logic low constantly. It can also
be configured to be active “high” or active
“low” in response to a SDI signal connect-
ed and “locked” to the selected SDI input.
If configured for active high an associated
LED, for example, would light whenever
a valid SDI source is connected to, and
“locked,” with the selected SDI input. If con-
figured for active low the LED would light
whenever a valid SDI is not connected to
the selected SDI input. The GPO can also
be configured to be active high or active
low in response to the on/off status of the
embedder function.
Technical Notes
Bitmap Image File
Requirements
The Model 5152 allows two bitmap (.bmp)
images to be stored and output when an
SDI input signal is not present. One image
has a pixel size of 1280 x 720 while the
other has a pixel size of 1920 x 1080. To
be stored with the Model 5152 the files
must be FAT32-compatible and have
names of img720.bmp and img1080.
bmp, respectively.
The reason two files are required is simple:
the Model 5152 does not have the ability to
digitally “scale” a 1920 x 1080 image down
to 1280 x 720. But it does have the ability
to store two unique files. Most users will
create a single image using a personal-
computer graphics program and then save