[lug] Off-topic: Contour line in image problem

[Ed Hill]

Glenn Murray wrote:

> More specifically, I have black and white jpeg images of a flame, in
> profile, in a tube.  I need to know the area of the flame front.  To
> find this I (am thinking I) need to draw a line along some (constant)
> intensity around the edge of the flame; a line dividing light from
> dark, as it were, from the top of the image to the bottom.  Then I
> need to know the line's length (from that I could calculate an
> estimate of the area).
> 
> Ideally the computer would draw this line or I could with a mouse, and
> I could mark start and end points.  The line may not reach to the tube
> edge, so I may need to extrapolate it.
> 
> Do you know of any software to do this sort of thing?  I may end up
> writing it myself.  Any help would be greatly appreciated.
> 

Hi Glenn,

If I understand your problem (and I believe I do), then you can do
this in MatLAB with just a few lines of code.  Not difficult.  I'll
be happy to give you a brief intro-to-MatLAB this weekend (and try
to help you write the code) if you want...

regards,
Ed

ps - Ob-Linux-note:  MatLAB v5.x and newer run fine on Linux...  ;-)


-- 
Edward H. Hill III, PhD
Post-Doctoral Researcher    |  Emails:   <ed at eh3.com>, <ehill at mines.edu>
Division of ESE             |  URL:      http://www.eh3.com
Colorado School of Mines    |  Phone:    303-273-3483
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