Method
VipsImagequadratic
Declaration [src]
int
vips_quadratic (
VipsImage* in,
VipsImage** out,
VipsImage* coeff,
...
)
Description [src]
Transform an image with a 0, 1, 2, or 3rd order polynomial.
The transform we compute:
x = x' + a : order 0 image shift only
+ b x' + c y' : order 1 + affine transf.
+ d x' y' : order 2 + bilinear transf.
+ e x' x' + f y' y' : order 3 + quadratic transf.
y = y' + g
+ h y' + i x'
+ j y' x'
+ k y' y' + l x' x'
where:
x', y' = coordinates of srcim
x, y = coordinates of dstim
a .. l = coefficients
The coefficients are in the input matrix, ordered as:
a g
--
b h
c i
--
d j
--
e k
f l
The matrix height may be 1, 3, 4, 6
::: tip “Optional arguments”
* interpolate: VipsInterpolate, use this interpolator (default bilinear)
::: seealso
vips_affine().