Newsgroups: sci.image.processing
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From: apurva@cs.sfu.ca (setenv DISPLAY hostname:0)
Subject: Colour filters
Message-ID: <1995Mar15.211218.2664@cs.sfu.ca>
Organization: Simon Fraser University
Date: Wed, 15 Mar 1995 21:12:18 GMT
Lines: 32


I have the following question.

I have an option of selecting a reflector(colour or otherwise) that is
circular in nature.  I want t capture the image such that only these
reflectors are bright and the rest of the picture appears to be dark.
In other words, these light reflectors are the only important in the
image.  At whoich point a simple thresholding scheme will separate out
the dark from the bright regions.  

Now, the question is: should I use a coloured reflector instead of
normal light reflector?  If so what colour would provide the sahrpest
contrast on a grayish(steel) background.  The system should work in
all conditions of light from dark to bright and the camera is equipped
witha light source.  The camera is b/w (ccd camera).  What kind of
light filter should I put on the front end of the camera to go with
the colour reflector.

The reflector does not have to be coloured one, however, I think that
it might be easier to separate out background from the foreground by
using a colour quite opposite to gray and filtering it out. (This
becuase we know the background i gray).

Please email me your suggestiosnas I do not read this ground regularly.
Email: apurva@cs.sfu.ca

Apurva PS: i have gathered a series of information about hough
transforms from various ppl.  Intrested ppl can email me and i will
send the file over.  POls be patient if it takes a while.



