Timestamp with the PCD files

[Ashik19]

Hi,

Can anyone suggest me how I can retrive the timestamp when converting the point cloud topic into pcd files using the pcd library (pcl_ros pointcloud to pcd ) ? It seems the timestamp field is missing in the pcd file .

Thanks

[dsb6063]

If you don’t see a option to include other fields, then you will need to download that source, modify the fields to include the timestamp. If not directly, maybe place or append it in a descriptor field as a string. Build the code and run it. Then, parse out the timestamp on the back end in the text file.

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[Ashik19]

Hi @dsb6063 , Thank you very much for your kind reply.

I have managed to retrive the timestamp of the point cloud in the .csv file format. Now, I want to convert it into pcd https://drive.google.com/file/d/1K6AuJSzY3hAbc3xQ0vwlV1RU3CLrg1Sh/view?fbclid=IwAR0W1xGbg7lqxDr-45q4P6cLGyFm2-bzhpJCQw0quPG9D70FwWJh7AyoL3Y

Now I want to convert it into the pcd file format. Can you recommend me any tool that can convert .csv into .pcd or any workaround method?

Thanks

[dsb6063]

Cloud Compare. It’s open source.

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[Ashik19]

@dsb6063 ,

I tried with cloudcompare but the problem is that since the csv file does not have the x,y,z value it can not create the proper pcd file. The problem is if I get the csv fiel I do not get the coordinates of the cloud, I can get the timestamps. But if I convert the bag file to the pcd I do not get the timestamps.

[dsb6063]

From reviewing the bag file all the data is contained within. rqt_bag shows all the data. You could "ballpark" the timestamps for an approximate extraction for coordinates. Also, you have all the data to run SLAM on cartographer using the sat_nav option for localization.

[Ashik19]

Hi @dsb6063 ,

Thank you very much for your kind suggestion. But I guess google cartographer needs very intensive data to run the SLAM and I am using only a 16 beams LiDAR.

I am just looking for a way to integrate the timestamp with the point cloud coordinate so that I can later geo-reference the cloud with the timestamps associated with my gps data.

Thanks

[k-mohit]

Hi @dsb6063 You have a great knowledge about Ouster LiDAR sensors, so it would be very nice of you to join our Ouster forum https://forum.ouster.at/ where you can contribute to this newly created support facility for Ouster LiDAR!

[Masoumehrahimi]

Hi

How do i change the timestamp of lidar and GPS into DateTime or duration scalars??

my timestamp is like this: 1607426698680700000