Re: How do I read an image into octave?

[etienne grossmann]

  Hello

# I've just successfully compiled octave under linux; I'd like to use it

  Hurra!

# to test some image processing algorithms.  But according to the info
# pages, images must be in octave's "img" format.  This is all very
# well, but how do I get a pgm/tif/gif/png image into that format?  Are
# there any file handling routines which will take, say, a 256 grey level
# pgm image and produce a matrix in octave?

# In other word, is there an octave equivalent to MATLAB's "imread"
# command?

  Not that I know of. I am sending you at the end of this mail two
functions : "loadpgm.m" and "savepgm.m". I also have a tentative
"saveppm.m" (I don't really know how ppm's are coded, but it seems to
work). I know, this is not the right list for code, but maybe Alasdair
doesn't subscribe to octave-source.

  If you're interested, I wrote a "bwlabel.m" function (finds
disctinct connex regions in a 0-1 image) and a "bwborder.m" function
(finds the border of regions in a 0-1 image).

  These little functions are quite useful, but not a substitute for
general image loading/writing/manipulating tools. With a good amount
of work, it should be possible to glue an image library onto
octave. That would require learning a good deal of octave internals
(I've chickened out of "liboctave") and the interface to, say,
"imlib", "the gimp" or some other image tool.


  Cheers,

  Etienne



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