🚀 go-pugleaf

In "non-rectangular ROI- *HOW*?"
    ph@physiol.ox.ac.uk (Patrick Haggard) writes


: Hi.  The title says it all.  I would like to extract a
: non-rectangular, and preferably freehand, ROI.  Has anyone
: any tips?
: - --------------------------------------------------------------------------
: Patrick Haggard                         Email (WORLD): ph@physiol.ox.ac.uk
: University Laboratory of Physiology     Email (JANET): ph@uk.ac.ox.physiol
: Parks Road,                             Tel. (0865) 272116
: Oxford, OX1 3PT                         Fax. (0865) 272469
: England
: - --------------------------------------------------------------------------


Patrick:

This is not a very satisfactory solution,  but when I want to do non-
trivial interactive image processing such as that which you describe, 
I convert my images to TIFF (viff2tiff), ftp them to my Macintosh, and
work in Adobe Photoshop. Then I ftp them back to the workstation, run
'tiff2viff',  and finish the job in Khoros.

Khoros is more-or-less constrained to
work with rectangular images; the usual way to deal with non-rectangular
regions of interest is with a mask image.  (In my greyscale morpho
routines,  I combine the mask or 'background' with the ROI or 'foreground'
in the same file by making the background pixels negative. This is not
a very general solution.)  

Unfortunately, since the VIPL library is a somewhat loose collection of 
routines contributed by many individuals,  only a few of the routines 
incorporate the masking idea.

Maybe the Khoros Group have some plans for more flexible ROI operations
up their collective sleeve.

Cheers,

     Greg D.

=================================================================
Gregory W. Donohoe, Ph.D., Assistant Prof.
Electrical and Computer Engineering
University of New Mexico        Tel: 505-277-6724
Albuquerque, NM 87131         email: donohoe@chama.eece.unm.edu

News flash:  "Eating causes cancer!"
=================================================================