1. Transform the image
2. Rigid Transformations, translation, rotation
3. Affine/projective transformation
4. Degree of freedom for different transformations
image filtering
image warping
g(x)= T(f(x))
change domain of image
g(x)= f(T(x))
Parametric Global Warping
origin(0,0)
rotate Θ
Transformation T
p’ = T(p)
A global and parametric T
– same for any p
– a few numbers(parameters)
As a matrix transform
p’ = Mp
Image Scaling(2D)
– multiply each components by a scalar
– uniform scaling scalar same for x, y
– Non-uniform not same
2D Rotation
(x’, y’), (x, y)
x’ = xcos(Θ)- ysin(Θ)
y’ = xsin(Θ)- ycos(Θ)