The computational sensor platforms are dual-processor, Intel (Pentium/Xeon) boxes running Linux. There is an assortment of these, representing various purchases experiments. The fastest currently have 2.0GHz Xeon processors. (With a set of 3.0GHz boxes to be fielded in the near future). They have a load of memory (up to 1GB) and a pile of local RAID storage (up to 280GB per box). They each have two BT848 digitizers, so they can handle dual cameras. You can put either the composite, or the S-video signals into these digitizers, but the S-video is better quality.
You can get monochrome into the KTV digitzers by running the Y signal from a s-video splitter into the green channel. To get color, you have to run the composite signal through a composite-to-rgb converter (there is one in the rack in the vision lab) and then into the KTV digitizer. A nuisance.
The Pan-tile-zoom cameras have 12 to 1 zoom (more on the Canon model), autofocus and autoexposure if you want it, and pan and tilt control as well. You can control the cameras with a remote (like for a TV) or from a computer over a serial line. There is a C++ library for doing this in with my other libraries, /u/nelson/programs/lib/Solaris/libcamera.a; source and demo programs in /u/nelson/programs/src/robot/pt_camera/[lib, bin]. The library supports both the Sony and Canon cameras. The C++ library does not access every possible function of these cameras. If you want to know more about the Sony camera you can take a look at the documentation of the serial control interface (this is a pdf document).
Currently, there are about 10 of the Sony cameras mounted in the vision lab, and some other loose on tripods or on the camera shelves. There is one Canon camera on the ceiling, and a lot of others in boxes, soon to be opened (10/2003)
You can use these cameras to remotely monitor what is going on in the
vision lab (or anywhere else one of them happens to be).
To do this, first make sure the camera is turned on.
Then bring up a remote X-window on the machine that has the camera and
digitizer hooked to it.
Make sure your DISPLAY environment variable is set to the machine
you are on. Run the program bt_showlive in my bin (~nelson/bin/PCLinux)
if the camera is attached to one of the Linux boxes with BT848 digitizers,
or the program ktv_showlive (in ~nelson/bin/Solaris) if it is attached to
a Sun machine with a KTV digitizer.
This should bring up a live image on your screen, transmitted over the
By default, the image is at half resolution and in monochrome, but
you can make it bigger or smaller, and run it in color
(assuming the digitizer is digitizing color) with various options
(use -h to get a list).
Then run the program camera_demo also in my bin/[PCLInux|Solaris].
This will let you control the camera (pan, tilt, zoom etc.) from
the keyboard. Run too many of these, and you will bog down the
local network. It is also considered poor etiquette to harass people
by spying on them or their terminals with these cameras.
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