[SOLVED] Are the elements of the Pose Matrix in Kitti Odometry dataset absolute or relative?

Are the elements of the Pose Matrix in Kitti Odometry dataset absolute or relative?

I am working with Kitti Odometry dataset. I know that poses.txt file's each row represents a flattened version of 4*4 Pose matrix such that:

r11 r12 r13 tx
r21 r22 r23 ty
r31 r32 r33 tz
0   0   0   1

My question is that are these values relative or absolute ? In other words for example is tx the relative translation in the x axis with respect to the state at the prior time (t-1), or is it the absolute translation in the x axis with respect to the initial position at time t=0 ?

Solution

The KITTI dataset poses are absolute position respect to the initial position.(By default an identity matrix 4*4) if you working on VO/SLAM tasks you need convert them to relative positions.

You can find more details in my previous answer: How to evaluate Monocular Visual Odometry results used the KITTI odometry dataset

And also KITTI dataset site: Visual Odometry / SLAM Evaluation 2012

Best regards.