How to set hyperparameters in SVM classification

Question

I am studying image classification using SVMs and it is generally defined as so...

N = number of training examples

W = is the weights

f(x, W) = dot product

λ is explained to be set through cross-validation however no mention is made as to how Δ is set.

I understand that the SVM loss function wants the score of the correct class to be larger than the incorrect class scores by at least by Δ, but they don't explain how Δ is derived.

In most of the examples it is define to be Δ = 1.0, with no mention as to how 1.0 was calculated. Is this value determined through trial-and-error (cross-validation)? How does one determine what should be the value?