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Fit geometric transformation to control point pairs

`tform = fitgeotrans(movingPoints,fixedPoints,transformationType)`

`tform = fitgeotrans(movingPoints,fixedPoints,'polynomial',degree)`

`tform = fitgeotrans(movingPoints,fixedPoints,'pwl')`

`tform = fitgeotrans(movingPoints,fixedPoints,'lwm',n)`

takes
the pairs of control points, `tform`

= fitgeotrans(`movingPoints`

,`fixedPoints`

,`transformationType`

)`movingPoints`

and `fixedPoints`

,
and uses them to infer the geometric transformation specified by `transformationType`

.

fits
a `tform`

= fitgeotrans(`movingPoints`

,`fixedPoints`

,'polynomial',`degree`

)`PolynomialTransformation2D`

object to control
point pairs `movingPoints`

and `fixedPoints`

.
Specify the degree of the polynomial transformation `degree`

,
which can be 2, 3, or 4.

fits
a `tform`

= fitgeotrans(`movingPoints`

,`fixedPoints`

,'pwl')`PiecewiseLinearTransformation2D`

object to control
point pairs `movingPoints`

and `fixedPoints`

.
This transformation maps control points by breaking up the plane into
local piecewise-linear regions. A different affine transformation
maps control points in each local region.

fits
a `tform`

= fitgeotrans(`movingPoints`

,`fixedPoints`

,'lwm',`n`

)`LocalWeightedMeanTransformation2D`

object to control
point pairs `movingPoints`

and `fixedPoints`

.
The local weighted mean transformation creates a mapping, by inferring
a polynomial at each control point using neighboring control points.
The mapping at any location depends on a weighted average of these
polynomials. The `n`

closest points are used to
infer a second degree polynomial transformation for each control point
pair.

[1] Goshtasby, Ardeshir, "Piecewise linear
mapping functions for image registration," *Pattern Recognition*,
Vol. 19, 1986, pp. 459-466.

[2] Goshtasby, Ardeshir, "Image registration
by local approximation methods," *Image and Vision Computing*,
Vol. 6, 1988, pp. 255-261.

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