Image Processing questions (Help!)
- To: mathgroup at smc.vnet.net
- Subject: [mg34671] Image Processing questions (Help!)
- From: vonschwartzwalder at mac.com (Duane)
- Date: Fri, 31 May 2002 04:27:17 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Hi all,
First of all, I'm new to Mathematica. I've been doing image
processing for some time and I thought I might get some use out of
this kind of package.
Now the questions. Any help is appreciated.
Is there a FAQ? I searched the new group and found nothing.
How do I read in a binary image? I have some image files that are
little-endian (I'm using a Mac, which is big-endian). The pixel
values are 4 byte float (I'm not sure if that's IEEE floating point).
I tried Import and BinaryImport. No real good solution there that I
could tell.
How do I do symbolic math with images? A good example is curvature.
I would like to write a notebook describing some of the work I am
doing in using differential geometry and level sets on images, but
when I try to develop an equation, I don't get much. I tried to take
the gradient of an image, symbolically. I expected to get a vector
with the partial derivatives in x and y. Instead I got back 0.
In := Grad[img, Cartesian[x,y,z]]
Out := {0,0,0}
I was kind of hoping for something like {d/dx(img), d/dy(img),
d/dz(img)}. Note that I've already learned that I am forced to carry
around the third dimension, even though images only have two. I'll
worry about that later (but if you know how to get rid of it now, I'm
open to suggestions).
Is there a GradientMagnitude operator, or equivalent? Curvature, for
example, is the divergence of the gradient divided by the gradient
magnitude.
Is there a good book for Mathematica? Something I can use as a
reference? I have the Mathematica book, but it's not very useful.
The entire documentation on VectorAnalysis occupies about a half a
page. The index is WRONG in several places, and there is no
hierarchical function index. Nothing on image processing.
Thanks,
duane