title: How to detect moving object on a moving conveyor using opencv
body: <p>I'm building a grading system for crabs. In this system, the animals (crabs) are placed in a moving conveyor and I need to identify dead or alive animals by detecting its motion based on images captured by a camera on this conveyor. 
  The color of conveyor belt is black. </p>
  
  <p>As the conveyor is always moving, so I can't apply methods using stationary camera like <a href="https://www.pyimagesearch.com/2015/05/25/basic-motion-detection-and-tracking-with-python-and-opencv/" rel="nofollow noreferrer">here</a>. Does anyone have a suggestion about motion detection of the animals in this case using opencv? I can use more than one camera if it's necessary. Thanks.</p>