zernike
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Name
zernike - zernike moment image of a gray scale
or binary image
Syntax
zernike [-n <n>] [-r] [-t <title>] <inimage> <outimage>
Description
The Zernike moment of order n and repetition m of
an image f(x,y) is defined as follows:
n+1 *
A(n,m) = ---- Sum Sum f(x,y)[V(n,m, x,y)]
pi x y
where x^2+y^2 <= 1
The image V(n,m, x,y) is the Zernike basis images of
order n and repetition m. These basis images are
complex and orthogonal. The Zernike moments are
essentially the projections of the input image onto
these basis images.
The original image can be reconstructed from the
Zernike moments. The N-th order approximation is given
by
^ N
f(x,y) = Sum Sum A(n,m) V(n,m, x,y)
n=0 m
The contribution or information content of the n-th
order moments is
I(x,y, n) = Sum A(n,m) V(n,m, x,y)
m
Restrictions
inimage must be single-band with pixel type unsigned byte.
Options
-
-n n
- Use moment order n. Default 0.
-
-r
- Reconstruct image from moments. Default: Compute the absolute
value of I(x,y, n).
-
-t title
- Use title for outimage.
See also
zer_mom(3), zer_con(3), zer_rec(3), zer_pol(3)
References
-
[1] A. Khotanzad and Y.H. Hong
- "Rotation invariant image recognition using features
selected via a systematic method",
Pattern Recognition, vol.23, no.10, pp.1089-1101, 1990.
-
[2] Thomas H. Reiss
- "Recognizing Planar Objects Using Invariant Image Features",
Lecture Notes in Computer Science, volume 676, pp. 17-20,
Springer-Verlag, 1993.
Return value
0 : OK
Files
xite/src/zernike/zernike.c
Author
Řivind Due Trier, Ifi, UiO.