Extract Streamlines arrival time

I’m trying to extract “time” information for streamlines as the total time a particle needs for traveling from the starting point (of the streamline) to a certain position.
I have already computed the streamlines associated to the Velocity vector by using the vtkStreamTracer class. However, I need also an information related to the temporal distance between two consecutive cells of the same streamline in order to compute the total arrival time.
I was thinking of exploiting as information the “InitialIntergrationStep” but I don’t know if it is the correct way to do it.