File Format
Video Files
Raw video files are provided as mp4
files, with corresponding
timestamps.txt
files. For the VI sensor, we recommend using the
original data from the ROS bag or the extracted frames rather than the
provided mp4
files as the latter suffer from quality loss due to
compression.
See the description in the Download section on how to extract
individual frames from the mp4 files. Note
that a bug somewhere between gstreamer and Matlab makes playing back
frames with Matlab’s VideoReader unreliable. It is recommended to play
back from the extracted frames using the CustomVideoReader
Matlab
class in the tools/matlab/
directory.
For the orientation of the camera axis, see the Extrinsic Calibration section.
IMU Files
The IMU data is stored in flat text files:
accelerometer.txt
(Tango): timestamp in seconds, acceleration in x,y,z (in m/sec^2)gyroscope.txt
(Tango): timestamp in seconds, angular velocity around x, y, z axes (in rad/sec)imu.txt
(VI sensor): timestamp in seconds, acceleration in x,y,z (in m/sec^2), angular velocity around x, y, z axes (in rad/sec)
For axis orientation of the IMUs, please refer to the Extrinsic Calibration section.
Pose (Ground Truth) Files
The ground truth and Tango pose files are flat text files that contain the pose as a 3x4 matrix $$ \cc{\mvec{P}:=\begin{bmatrix}\mvec{R}\ \mvec{t}\end{bmatrix}} $$ corresponding to the body(rig)-to-world transform: $$ \cc{\ctrans{T}{B}{W} = \begin{bmatrix}\mvec{R}\ \mvec{t}\end{bmatrix}} $$ Each line in the pose file starts with a timestamp (in seconds) and is followed by the matrix $\cc{\mvec{P}}$ in row major format, i.e:
timestamp(sec), $\cc{\mvec{P}_{11}}$, $\cc{\mvec{P}_{12}}$,$\cc{\mvec{P}_{13}}$, $\cc{\mvec{P}_{14}}$, $\cc{\mvec{P}_{21}}$, $\cc{\mvec{P}_{22}}$,$\cc{\mvec{P}_{23}}$, $\cc{\mvec{P}_{24}}$, $\cc{\mvec{P}_{31}}$, $\cc{\mvec{P}_{32}}$,$\cc{\mvec{P}_{33}}$, $\cc{\mvec{P}_{34}}$.
Input files for benchmarking must be produced in this format as well.