Clarification on Data Format of Trajectory in Future Localization Dataset

Hello,

Can someone please explain the data format of the trajectory in the Future Localization dataset? There is no information on what t_n or b is in the example provided below:

[up.x up.y up.z] TrajLength(n) [t_0 C_0.x C_0.y C_0.z b b] [t_1 C_1.x C_1.y C_1.z b b] ... [t_n ...]

Additionally, could someone explain how the trajectory relates to the camera frame?

Thanks in advance!