out of order frames when recording with libcamera-raw

[fiepfiep]

For a scientific test I needed to record sequential raw images.
I used something like this:
rpicam-raw -t 20000 --shutter 2000 --gain 1.0 --fps 30 -o image_%04d.raw

Then, I used a python script to stitch the images together into a single video.
However when looking at the video ( or individual images) the frames are not always in the right order.
I can tell by capturing images of a digital chronometer or a constant moving object

Is this a known issue?

[naushir]

This really should not be happening, and certainly libcamera cannot return buffers out of order.

Can you quantify how frequently this is occurring?