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[oats-sig] Re: open gazer

stephen emslie stephenemslie at gmail.com
Wed Oct 3 23:31:16 BST 2007

Article: [oats-sig] Re: open gazer

Hi

It turns out the opengazer readme has been updated with answers to
most of the questions that I encountered, so rather than repeat what
has been written there I'll just point you on to the homepage [1] and
the readme [2]

[1] http://www.inference.phy.cam.ac.uk/opengazer/
[2] http://www.inference.phy.cam.ac.uk/opengazer/README

I can confirm that the apt-get installation of libcv-dev and all that
does work on ubuntu.

I found installing vxl a bit tricky as I am not familiar with cmake,
but the vxl page does a good job of expaining it:
http://vxl.sourceforge.net/releases/install-release.html

Just make sure to set BUILD_SHARED_LIBS to ON. I also changed
CMAKE_INSTALL_PREFIX on my system to /usr as I think it was /usr/local
which ubuntu doesn't include in its search for shared libraries.

also, I had trouble with the latest release, so perhaps use vxl-1.8.0
till you have things working.

I also found the Makefile quite fiddly in opengazer 0.1.1, but that
seems to have been improved in 1.1.2. The only thing I had to do was
change the VXLDIR to reflect that '/usr' prefix on my system (it is
set to /opt by default).

The rest is described well in the makefile. I imagine there will
probably be some hackery about the webcam. I found that I definitely
needed the

"sudo modprobe pwc size=vga"

line before anything would work for me. One more catch I'm afraid.
Ubuntu 2.6.20-16 seems to have removed the pwc driver, rather
unhelpfully (it wouldn't even build under ubuntu!). If you're using a
camera that requires this driver than roll back to 2.6.20-15 like me.
I think the next webcam I buy will have to be supported by UVC or
SPCA5XX or something else that actually works in ubuntu. I'll have to
investigate the driver issue more thoroughly.

I hope that helps a bit. Please respond with any problems you have and
perhaps we can figure them out. Personally, I'm learning a lot of this
as I go along so I welcome any feedback from more experienced linux
hackers.

Good luck!

Stephen

On 10/3/07, stephen emslie <stephenemslie at gmail.com> wrote:
> Hi Tom
>
> Thanks for the offer of help on Windows. I'm sure that platform will
> be a barrel of fun, so probably the first thing to investigate is
> whether we can get opengazer built and running. I _think_ that most of
> the dependencies can be built on windows, but perhaps we should see
> what the author has to say.
>
> Stephen Emslie
>
> On 10/2/07, Tom Nabarro <whizz2000 at hotmail.com> wrote:
> >
> >  511"
> > The next step is to start interpreting the calculated gaze positions into a
> > switch activation. opengazer outputs everything to a port as it works, which
> > should make things a bit easier. Any suggestions on good assistive software
> > I can play around with? I hear there's this great "Jambu" thing... :)
> >
> > "
> >
> > in response to this from Stephen, if you need anything done on Windows I
> > could write a socket application to listen for that port and then interpret
> > the gaze positions     to detect for switch activationbased on the threshold
> > method at first.  I might have the wrong end of the stick, but if any of
> > this sounds useful let me know.
> >
> > ________________________________
> > Get free emoticon packs and customisation from Windows Live. Pimp My Live!
>


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