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

[D. Stimits]

Ed Hill wrote:
> 
> 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...

Just a note, Octave is almost a direct replacement for MatLAB. Or so I'm
told. I've used Octave for some basic stuff, and the literature claims
the many MatLAB files can be directly read or imported from MatLAB. I
think it can also save in MatLAB format. The GUI version of Octave is
GOctave, it's slightly less clumsy than the pure command line Octave. I
still prefer Mathematica, but my student edition expired long ago, and
it is *way* too expensive to get a real copy. There is a far less
expensive commercial package that is similar to Mathematica, but I
forget the exact name...it is the name of some kind of wood...I want to
call it "Pine" or "Balsa", but of course we all know those are something
else...wish I could recall the substitute package name. Aha! I remember
now, just going through a list of tree/wood names...Maple.

D. Stimits, stimits at idcomm.com

> 
> 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
> Golden, CO  80401           |  Fax:      303-273-3311
> 
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