Rosenfeld and Johnston RJ73

Corner strength. $k$-cosine of the angle between the $k$-vectors is used, which is defined as

$$c_{ik} = \frac{(\aik{i}{k}\cdot \bik{i}{k})}{\vert\aik{i}{k}\vert \vert\bik{i}{k}\vert}$$ (3)

Selection procedure. Starting from $m=\kappa N$, $k$ is decremented until $c_{ik}$ stops to increase: $c_{im} < c_{i,m-1} < \ldots < c_{in} \nless c_{i,n-1}$. $k=n$ is then selected as the best value for the point $i$. A corner is indicated in $i$ if $c_{in} > c_{jp}$ for all $j$ such that $\vert i-j\vert \leq n/2$, where $p$ is the best value of $k$for the point $j$.
Parameter. The single parameter $\kappa$ specifies the maximum considered value of $k$ as a fraction of the total number of curve points $N$. This limits the length of an arm at $\kappa N$. The default value is $\kappa = 0.05$.