Transformation matrices affine vs. euclidean is there a difference between an affine transformation an the euclidean transformation mentioned in this tutorial?
Is an affine transformation a type of euclidean transformation?

No, the the "Euclidean warping" is a special type of affine transformation.
Affine transformations are very general. They are made up of a nonsingular linear transformation plus a translation. The author explicitly describes Euclidean warping as encompassing scale, rotation and translation only. In other words, he wants to carry out the geometry of Euclidean similarity.
Examples of affine transformations that are not Euclidean similarity transformations (as described in the paper):


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*Reflections

*Shear mappings
