# Large external sensors data file for slam

**URL:** https://discourse.paraview.org/t/large-external-sensors-data-file-for-slam/16532
**Category:** LidarView, Lidar, and SLAM
**Created:** [April 25, 2025, 11:06pm UTC](https://discourse.paraview.org/t/large-external-sensors-data-file-for-slam/16532 "2025-04-25T23:06:35Z")
**Posts on this page:** 3
**Page:** 1

<div class="post-metadata">

### Author: ![uasdev](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/u/a9adbd/32.png) [@uasdev](https://discourse.paraview.org/u/uasdev)
#### Post date: [April 25, 2025, 11:06pm UTC](https://discourse.paraview.org/t/large-external-sensors-data-file-for-slam/16532/1 "2025-04-25T23:06:35Z")

</div>

How do we deal with a large external sensor data file (.csv) when running a slam (offline)?

For example, I had my lidar “on” for about an hour. I looped through all .pcap files for this capture to extract the lidar time frames, which is almost 200 million time frames. I used these times to synchronize with my GPS/IMU data to run the slam (offline) algorithm.

---

<div class="post-metadata">

### Author: ![Gatien\_Ferret](https://discourse.paraview.org/user_avatar/discourse.paraview.org/gatien_ferret/32/9789_2.png) [@Gatien\_Ferret](https://discourse.paraview.org/u/Gatien_Ferret)
#### Post date: [May 2, 2025, 9:32am UTC](https://discourse.paraview.org/t/large-external-sensors-data-file-for-slam/16532/2 "2025-05-02T09:32:53Z")

</div>

Hi Alex,

As of now, you would need to split your csv file to files that correspond (or at least include) the timesteps contained in ech of your pcap file.

If I understand correctly, this is already what you have done, right ?  
Did you encouter issues with that approach ?

---

<div class="post-metadata">

### Author: ![uasdev](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/u/a9adbd/32.png) [@uasdev](https://discourse.paraview.org/u/uasdev)
#### Post date: [May 2, 2025, 7:16pm UTC](https://discourse.paraview.org/t/large-external-sensors-data-file-for-slam/16532/3 "2025-05-02T19:16:02Z")

</div>

Yes, I have my .pcap files for a single drone data collect split into 500MB each, with corresponding .csv files. It seems like this can be handled well using an intel core ultra 7 with 32 GB RAM.

The outputs look like the right “shape”, however, it looks like it is “projected” onto the wrong axis. I believe that is a separate question, so I will post a new question on the discussion board. Thanks!