spatialTransformPoly edit page

a displacement that varies polynomially across the frame

Degree 1 is an affine and could equally be a spatialTransformShift - inv converts to one, since a matrix has an exact inverse where a polynomial does not. Degree 2 is what mops up the residual curvature a projective stage leaves behind.

The coefficients describe the DISPLACEMENT, not the mapped position, so the identity is c = 0.

Syntax

T = spatialTransformPoly(c,degree)
T = spatialTransformPoly.fit(posA,posB,'degree',2)
T = spatialTransformPoly.fit(posA,posB,'degree',2,'weights',w)

Input

c m × 2 coefficients, one column per displacement component
degree 1 or 2
posA, posB vector3d, the same points in the two frames
w double, one weight per point

Output

T spatialTransformPoly

Class Properties

c m x 2 coefficients against [1 x y] or [1 x y x^2 xy y^2]
degree 1 or 2

See also

spatialTransform spatialTransformShift spatialTransformTilt