Re: Using RSSI to locate an object

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#1997

From: Mark Harriss
Date: Wed, 21 Mar 2007 12:39

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Josh916 wrote:
> 
> Thanks for everyones help, especially David Jones, I will be going
> with the visual recognition. It was originally my first choice though,
> as you do, I wanted to exhaust all possible options before finalising
> the decision as you never know there might of been an easier, more
> efficient way.
> 
> Josh
> 

I've worked on someone else's image processing software that used a
camcorder to track a lizard's frame to frame movement down a small track
~1.2M long or so.

You'll need to correct for parallax unless the camera is very high above
the tank, so having a X,Y marks around the edges of the tank would help.

Python and Python Imaging Library was used to convert the colour image
to greyscale first and then to two bit black and white if a pixel was
either side of a set threshold value. This gave a black background with
a white moving object on it that could be scanned vertically in my case
to give the amount of movement in pixels which was then corrected for
parallax and converted to millimetres.

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Subject: Re: Using RSSI to locate an object
From: Mark Harriss <user@example.net>
Date: Wed, 21 Mar 2007 22:39:46 +1000
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