Camera sampling rate

#1

Hello,

I learned from one of NuScenes papers that camera’s sampling frequency is 12 Hz. However, I was confused by inconsistent time stamp difference between consecutive images when looking into CAM_Front folder of mini dataset. I have observed 50 ms, 100ms and even 200 ms. Is that expected?

Thank you.

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#2

Hi.

  • In general the time diffs can vary a bit, but should be around 1/12Hz = 83ms.
  • One reason you may be seeing these large gaps is that you are not looking at the samples folder as well. That probably explains the 200ms.
  • The strict synchronization requirements are only on the keyframes.
  • Don’t look at the file names, as sometimes multiple scenes are (more or less) consecutive from the same log. Instead work with the devkit and loop through the sample_datas in a scene.