Open Hero941215 opened 1 year ago
pierdell
commented
1 year ago Hi,
The timestamps the frame are indeed set between 0 and 1, but all datasets are acquired at a frequency of 10Hz. To obtain the real timestamps, thus you can use the following formula:
$t_a = tr 0.1 + 0.1 I{frame}$
Where $I_{frame}$ is the index of the frame, and $t_r$ the relative timestamp.
Hero941215
commented
1 year ago Thank you very much for your reply.
According to the formula you provided, when we can obtain the real timestamp of each point in a frame of point cloud, the relative timestamp can be further calculated, and the range is within [0,1].
However, the point cloud in KITTI-raw is stored in txt format and provides [x, y, z, intensity]. So, how is the real timestamp ta obtained?
pierdell
commented
1 year ago We provide a link to the raw-kitti datasets (which have timestamps).
To obtain this timestamps, we took the azimuth (yaw) angle and linearly interpolated between 0 and 1 Starting 0 towards the back of the car (180° with respect to the X-Axis), and going clockwise.
See the picture of the timestamps (blue means 0, red 1):
Hero941215
commented
1 year ago We provide a link to the raw-kitti datasets (which have timestamps).
To obtain this timestamps, we took the azimuth (yaw) angle and linearly interpolated between 0 and 1 Starting 0 towards the back of the car (180° with respect to the X-Axis), and going clockwise.
See the picture of the timestamps (blue means 0, red 1):
Thank you very much. I understand how the timestamp was obtained
Hello authors,
You have completed a great job!
During the process of studying your article and code, I found that the relative timestamp range of each point you provided is [0,1]. The classic LOAM algorithm also seems to have a method for calculating relative timestamps (they use the first and last points of a frame to determine the angle at the beginning and end of the frame), and the calculated timestamps are not within the range of [0,1].
Therefore, I would like to know how you process the original point cloud data to obtain the relative timestamp of each point within the range of [0,1]?