| Mij {SpatialVx} | R Documentation |
Raw Image Moments.
Description
Calculate the raw Hu image moment Mij.
Usage
Mij(x, s, i = 0, j = 0)
Arguments
x |
A matrix. |
s |
A two-column matrix giving the location coordinates. May be missing in which case they are assumed to be integers giving the row and column numbers. |
i, j |
Integer giving the moment order for each coordinate x and y, resp. |
Details
The raw moment M(ij) (Hu 1962) is calculated by
M(ij) = sum(x^i * y^j * Im[i, j])
where x and y are the pixel coordinates and Im is the (image) matrix. Various useful properties of an image may be gleaned from certain moments. For example, the image area is given by M(00), and the image centroid is (M(10) / M(00), M(01) / M(00)). The image orientation angle can also be derived.
Value
A single numeric giving the desired moment is returned.
Author(s)
Eric Gilleland
References
Hu, M. K. (1962) Visual Pattern Recognition by Moment Invariants. IRE Trans. Info. Theory, IT-8, 179–187.
See Also
Examples
data( "geom000" )
Mij( geom000 ) # area