title: Capture data from intel realsense cameras pre-trigger
body: <p>I'm hoping someone may be able to give me a suggestion or two to try...</p>
  <p>Im using Raspberry PI 4 and intel RealSense D455. I have an external trigger(button) and I would like to record (for example) 5 seconds before the trigger event and save it into memory (ring buffer). Is there a way to do this with python and Intel RealSense camera.
  I know picamera has this option: <a href="https://picamera.readthedocs.io/en/latest/recipes1.html#circular-record1" rel="nofollow noreferrer">https://picamera.readthedocs.io/en/latest/recipes1.html#circular-record1</a></p>
  <p>I will be thankful for any advice.</p>
  <p>Many thanks,
  Nejc</p>