Let $f:X \dashrightarrow X$ be a Crepant birational map, i.e. a birational map that preserve the canonical class.

Someone knows another caracterization of Crepant birational map?

In particular, 
Is $ f: \mathbb{P}^n \rightarrow (\mathbb{P}^1)^n , [x_0:\dots :x_n] \mapsto ([x_0,x_1],[x_0,x_2], \dots ,[x_0,x_n])$ a Crepant birational map?