Studio Technologies 5150 V.2 - Manual (Page 22)

Issue 3, September 2013 Model 5150 User Guide
Page 22 Studio Technologies, Inc.
Model 5150
Video Generator Module
viewing is active. And, just to clarify, if a
signal is present on the Model 5150’s
selected SDI input it will be passed on to
the coaxial (BNC) and, if present, optical
SDI outputs. The moving image will never
overlay an input signal—it can only overlay
on top of the stored image.
GPI and GPO
Model 5150 module with serial numbers
of 00251 and later include a GPI (general-
purpose input) and a GPO (general-purpose
output) function. Depending on the appli-
cation, connections may have been made
to the GPI and the GPO. As of the date of
this User Guide the Model 5150’s firmware
(embedded software) does not support the
performance of any action in response to
the GPI function changing state. Future
firmware versions may implement an action.
(For now it’s just something ready for the
future.)
The GPO may be connected to an LED
indicator. A configuration choice allows the
GPO to be active “high” or active “low” in re-
sponse to a SDI signal connected to the se-
lected SDI input. If configured for active high
an associated LED would light whenever a
valid SDI source is connected to the select-
ed SDI input. If configured for active low the
LED would light whenever a valid SDI is not
connected to the selected SDI input.
Technical Notes
Bitmap Image File
Requirements
The Model 5150 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 5150 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 5150 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 it in the two
required formats. So when the Model 5150
generates either of the two images (“720” or
“1080”), a user will see what appears to be
an identical image. But there is no reason
why the two images (“720” and “1080”) have
to be based on the same original graphics.
Studio Technologies chose to create two
different “720” and “1080” bitmap files that
are pre-loaded in the Model 5150 at the time
of manufacture. They feature two unique
background images with text highlighting
the main requirements for updating them.
While the two bitmap files (img720.bmp and
img1080.bmp) are “standard” in the sense
that they are FAT32-compatible and have
the extension .bmp, they must adhere to one
important requirement that not all personal-
computer graphics programs support. Their
DIB (bitmap information header) must be a
BITMAPINFOHEADER type. The Microsoft
Paint and Adobe Photoshop applications
will create .bmp files that meet this require-
ment. But some other programs may pro-
duce non-compatible files. For example,
the open-source GIMP graphics program
is very good but appears to save .bmp files
only as a BITMAPV4HEADER type. These
are not compatible with the Model 5150.
The possibility that various .bmp files will
have different header types doesn’t seem