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DIGITAL SIGNAL PROCESSING
Build Custom Real-Time Video
Applications Quickly and Easily
You can use a board equipped with all required video I/O and
a Virtex-II FPGA to rapidly develop custom video processing functions.
by John L. Smith
Principal Engineer
Titan Corp., AP&D Division
john.l.smith@titan.com
Visually guided tele-operation is becoming
ubiquitous in a variety of fields, including
medicine, defense, and industry. A key
requirement is low latency – there should
be minimum delay between capturing
video at the sensor and displaying it at the
remote viewer. With training, people can
get used to as much as a half-second of
delay, but often the result is vehicle oscillation,
as the operator over-corrects controls
without having the intuitive
immediate feedback.
Titan Corporation’s Advanced
Products and Design Division works with
aerospace defense primary contractors,
Figure 1 – Predator UAV
Figure 2 – Ground station console
who provide unmanned aerial vehicles
(UAVs) to the DoD. Figure 1 shows a
General Atomics Predator UAV, and
Figure 2 shows a ground station used for
UAV remote control.
In surveillance missions, MPEG-2
encoded video from a pan-tilt-zoom
(PTZ) camera mounted on the UAV is
transmitted to a ground station. There the
imagery is presented on a console to the
operators. For the most effective control
of the camera and vehicle, we had to
reduce delay through the MPEG-2
decoder to less than 75 ms.
To accomplish this task, we used our
commercial off-the-shelf multimedia video
processing board, the VigraWATCH.
VigraWATCH (VW) is equipped with a
Xilinx ® Virtex-II FPGA and an IBM
PowerPC 440GP (PPC) processor. This
74 Xcell Journal Winter 2004